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In polar ice core drilling, continuous coring with air reverse circulation (CCARC) technique can increase the drilling rate, reduces pollution, and prevents air circulation loss. Dynamic collisions occur between ice chips and ice core in the drilling process, resulting in changes in the ice core ascent characteristics. Based on this, the Computational Fluid Dynamics-Discrete Element Model (CFD-DEM) coupling analysis method is used to simulate mixed flow ascent during continuous coring with air reverse circulation. This paper investigates the ice core ascent characteristics with consideration of the influence of the dynamic interaction mechanism between ice core and ice chips. The results show that the contact force of the ice core due to ice chip collision plays an essential role in the ascent. The contact force considering the ice chips influences, the drag force increases 23–85% compared with without. With the reduction of air mass flow rate, the impact of contact force is more significant. The dynamic collision between ice chips and the ice core reduces the pressure drop. The contact force and pressure drop are used as the performance indexes of the influence of ice chips on the ice core. Air mass flow rate has the most significant impact on the contact force and pressure drop. Other factors greatly influence the contact force but have little influence on the pressure drop. This paper considers the influence of ice chips on the ice core ascent during the air reverse circulation drilling (ACD) process. Traditional ice core ascent models do not consider dynamic interaction mechanisms, leading to inaccurate results. The research results provide an essential reference value for polar core drilling. • The mixed flow ascent model of air, ice core and ice chips during polar coring drilling is established. • The ascent characteristics of ice core considering the impact of dynamic collision of ice chips are studied. • According to the numerical simulation results, the optimal direction of coring drilling is proposed. [ABSTRACT FROM AUTHOR]

Permafrost in the Qinghai-Tibet Plateau (QTP) accounts for a total area of 1.05 × 106 km2. Many highway engineerings have been through the permafrost regions of the QTP, including the Qingkang Highway (QKH), Qinghai-Tibet Highway (QTH), and Gonghe-Yushu expressway (GYE), and the Qinghai-Tibet expressway (QTE) will be constructed in the future. Under the action of roadbed construction and global warming, permafrost under roadbed is degraded and causes serious pavement damage. Although many useful cooling measures have been applied to prevent permafrost degradation, their application presents significant challenges on account of the stronger endothermic action of asphalt pavement. This paper summarizes the working principle of existing cooling measures, and ascertains the relationship between pavement damage and ground temperature distribution of permafrost under roadbed. Based on the relationship, geotemperature distribution criteria and requirements for the cooling measures are proposed, and some suitable composite structures and measures are suggested. The results reported in this paper can provide a valuable guidance for the design and construction of the QTE in the future. • Relationship between temperature distribution and damage characteristics is revealed. • Geotemperature distribution criteria for the cooling measures are established. • Some composite measures are proposed for roadbed in permafrost regions of the QTP. [ABSTRACT FROM AUTHOR]

Ships that are navigating in ice covered waters are at risk of colliding with icebergs or ice floes, which can lead to severe damage to the ship's hull in certain conditions. Predicting these loads is of great importance for the design and safety of ships. Ice loads are driven by a range of parameters, including ice properties such as the compressive strength, the geometry of the ship's hull and values related to the interaction (e.g. impact velocity). Classification rules and requirements for polar vessels account for these parameters to a certain extent. However, sea ice exhibits not only variability of its properties but also the geometry of the ice shows a high degree of diversity: icebergs and ice floes exist in multiple different shapes. Therefore, this paper addresses the ice-structure interaction process, focusing on the influence of the initial ice contact shape and its impact on the local load. Additionally, the paper explores the feasibility of pinpointing geometric parameters of the ice responsible for influencing these loads. Ultimately, understanding which ice shape in contact poses the greatest risk would be valuable for improving numerical simulations for the worst case scenario and, consequently, enhancing the safety of ships in ice-prone environments. To achieve this, a comprehensive drop tower test campaign on a small-scale has been conducted at the test facilities of the Hamburg University of Technology. In these experiments, single impacts of differently shaped ice specimens against a rigid 50 mm steel plate in normal direction were investigated. In the experiments, a drop hammer was released from a predefined drop height to realize a brittle failure of the ice at an interaction velocity of about 2000 mm/s. This falls within the lower range of ship-ice interaction speeds. The drop hammer fell onto the ice specimen which was positioned centered underneath the drop hammer. The investigated specimen geometries were cylindrical shapes of 200 mm diameter with varying caps of cone, dome, wedge, ellipse and other shapes. Overall, 27 different shaped ice specimens were tested. The analysis includes the failure behavior of the ice specimens and the load introduced by the specific contact shapes. Two main failure modes were observed depending on the ice geometry, which showed significant differences in the load magnitude. Further relations between the initial contact area, the cone angle, and the specimen length to the peak force, maximum pressure, and energy were identified. • Ice shape affects load magnitude in impacts with rigid structures, showing distinct failure behaviors. • Two main failure behaviors identified: instant global failure and local crushing before global failure. • The failure bahavior governs the energy and peak force. • Initial contact area and ice specimen sharpness play pivotal roles in determining peak force and energy absorption. • Sensitivity to misalignment is notable, especially for specimens with a large initial contact area, stressing precise alignment. [ABSTRACT FROM AUTHOR]

Merchant vessels often require icebreaker (IB) assistance to create safe pathways and improve efficiency when navigating in the Baltic Sea. Since IB resources are limited, an accurate estimation on the need for IB assistance is important. Whether IB assistance is needed depends on multiple factors. While practical experience from captains is naturally a source of valuable information for the decision on the need for IB assistance, systematic analysis of the reasoning is limited. The primary aim of this paper is to holistically investigate the influencing factors and their effect on estimating the need for IB assistance through data-driven techniques. Based on a comprehensive list of potential factors, different of data such as traffic history, environmental conditions, and ship specifications are gathered to present complex navigational scenarios. Each scenario is labeled by different navigation modes (independent navigation or IB assistance), laying the foundation for influencing factor identification and effect quantification. Logistic regression is applied to evaluate the effect of the factors on the need for IB assistance. The results show that the impact of the factors is diverse, and ridged ice concentration has the most significant impact. The effectiveness of identified factors is measured by comparing it to that of the factors that have been implemented by the existing studies (e.g., the combination of ice concentration, thickness, and ship ice class, or only ship speed). By considering the factors in this study, the classification performance can be improved by at least 5.6%. The findings in this paper can provide insights for predicting IB workloads and optimizing IB resources and have the potential to support the development of an intelligent decision-support system for winter navigation. • A data-driven model was proposed to analyze navigation mode determination in ice-covered waters. • Influencing factors for the need for icebreaker assistance in ice were quantitively identified and assessed. • The impact of various influencing factors on ships with different ice classes was examined. • The innovation of influencing factor analysis was highlighted through model performance comparison. [ABSTRACT FROM AUTHOR]

The risk of sea-spray icing on vessels and marine structures in cold regions highlights the need for an accurate and robust marine-icing estimation model. To develop such a model, it is crucial to accurately determine the quantity of liquid water available for freezing on the structure, as it directly influences ice formation. As sea spray constitutes the primary source of liquid water contributing to marine icing, researchers have often focused on measuring sea-spray flux from field campaigns to establish empirical expressions for icing estimation. However, due to the lack of standardised equipment or methods for such measurements and concerns regarding the generalisability and transferability of resulting empirical expressions, researchers have resorted to employing a variety of equipment and techniques tailored to their specific research requirements. Nevertheless, these approaches have inherent limitations. This paper introduces a novel spray collector device inspired by the cyclone separator, capable of performing real-time autonomous spray flux measurements on vessels and moving platforms. The collector is constructed using carbon fibre-infused nylon material, ensuring durability in harsh cold marine climates. Computational Fluid Dynamics (CFD) simulations and laboratory tests demonstrate that the design of the new collector is more efficient than that of the previously employed devices, particularly at higher wind speeds. The device is currently deployed on a fish farm in Northern Norway in order to assess its performance in field conditions. The paper also shares preliminary findings, experiences, and limitations encountered during the deployment period. • The paper introduces the SPRICE sea spray collector, inspired by the cyclone separator design for sea-spray flux measurement. • CFD simulations and lab tests demonstrate that the collector is more efficient than previous devices at higher wind speeds. • The collector is 3D printed with carbon fibre-infused nylon for durability and corrosion resistance in marine conditions. • The collector enables autonomous, real-time data collection from moving platforms such as ships and marine structures. • The collector's real-world performance is evaluated during its field deployment on a fish farm in Northern Norway. [ABSTRACT FROM AUTHOR]

With the construction of railways on plateaus, the slab tracks of railways are facing rigorous temperature challenges and adverse thermal effects. This paper analyzed the temperature field and thermal effects of the CRTS III slab track on plateaus. Firstly, the pivotal thermal parameters of the geotextile and rubber pad of the slab track were obtained by tests. Subsequently, a coupled thermal-fluid-solid model for the CRTS III slab track on plateaus was established, followed by experimental validation. Based on the model, the temperature field and thermal effects of the slab track on Tibetan Plateau were revealed. The main conclusions are as follows: the thermal conductivity, specific heat capacity, and heat flux of the rubber pad and geotextile were very small, resulting in poor heat conductivity. The temperature of the track on plateaus showed obvious non-uniformity along both lateral and vertical directions, and changed with time significantly. Compared with that on the plain, the CRTS III slab track on the plateau had low temperature and large temperature variations. Compared with the conventional simplified temperature load, the spatial temperature field can fully reflect the non-uniform thermal effects of the slab track on plateaus. The method and conclusions presented in this paper can provide scientific guidance for the construction, operation, and maintenance of railways on plateaus. • The thermal parameters of rubber pad and geotextile of the CRTS III slab track were obtained by tests. • The thermal-fluid-solid model for the CRTS III slab track on cold plateaus was established. • The temperature field characteristic of the CRTS III slab track on cold plateaus was revealed. • The influence of spatial temperature fields on the thermal effects of the slab was explored. [ABSTRACT FROM AUTHOR]

Freeze-thaw (FT) cycles are considered to be a potential threat to the hydro-mechanical behavior of subgrade soils in seasonal frozen regions. Enhancing the resistance of the soils to FT cycles therefore becomes a pressing problem that needs to be solved. This paper developed a durable polyacrylate intercalated bentonite superabsorbent polymer (BT-SAP) employing the solution polymerization method, which is a novel hybrid polymer material with the function of reducing the sensitivity of subgrade soils to FT cycles. To evaluate the effects of BT-SAPs on the hydro-mechanical behavior of subgrade silts experiencing FT cycles, the 3D pore structure, volumetric strain (ε v), soil-water characteristic curve (SWCC), and resilient modulus (M R) of the soil modified with BT-SAPs were determined using a series of laboratory tests. Specimens with three BT-SAP contents (BC) compacted at their respective optimum moisture content and maximum dry density were first subjected to different numbers of FT cycles (N FT). Then, they were dried or wetted to specific moisture contents (w) before the determination of (i) SWCCs using the filter paper method and (ii) M R from cyclic triaxial tests. Finally, the 3D pore structure of specimens after FT cycles was measured by X-ray μ-CT. Experimental results show that the viscous and micro-swelling effects of the generated BT-SAP-water-gels can inhibit the emergence and development of larger pores and cracks inside the soil after FT cycles. The addition of BT-SAPs significantly reduces the sensitivity of the soil's volume and water retention capacity to FT cycles. The M R decreases with N FT but increases with BC. The important finding is that an optimal BT-SAP content of 0.25% was determined suitable for fine-grained subgrade soils. In addition, an artificial neural network (ANN) model was developed using 1200 sets of the M R measurements obtained in this study and well predicts the M R considering several factors such as BC, N FT , w , dry density, and stress levels. This study provides useful guidelines for the application of BT-SAP materials in subgrade engineering in seasonal frozen regions. • Developed a novel hybrid polymer (BT-SAP), which has the function of reducing the sensitivity of soils to FT cycles. • The mechanism of BT-SAP-water-gels inhibiting the development of large pores in the soil after FT cycling was studied. • The effect of BT-SAPs on the soil's volumetric and water retention capacity after FT cycles was evaluated. • Established an ANN model to predict the M R considering the influences of BC, N FT , w , ρ d , σ c , and σ d. [ABSTRACT FROM AUTHOR]

Automated avalanche detection has previously relied on satellite imagery, which is typically unsuitable for real-time monitoring due to long revisit times. To address this, we propose automating avalanche detection using photographs taken from the ground. This paper introduces image classification and avalanche segmentation tasks on a publicly-released dataset of 4090 photographs annotated by experts. Using the ResNet and YOLO architectures, we achieve avalanche detection F1 scores of 94.4% per image and 65.4% per avalanche region, demonstrating the potential that this method offers for avalanche monitoring. In contrast with existing approaches, we label images by avalanche type into four distinct categories: glide, loose-snow, slab, and no avalanche. This labelling scheme provides more detail on avalanche events than binary labels and is shown to improve model F1 scores. Moreover, our models do not require a digital elevation model, simplifying application to new areas. Trained models can be used for real-time avalanche monitoring and to gather temporally continuous data for the improvement of existing avalanche forecasting models. The code and dataset are available at github.com/j-f-ox/avalanche-detection. • Deep learning enables automated avalanche detection in webcam images. • Labeling avalanche data by release type improves model results. • ResNet, YOLO, and VGG are utilized to find avalanches in photos taken from the ground. • A dataset of 4090 avalanche photographs annotated by experts is publicly available. • The avalanche dataset contains 7228 outlined avalanches. [ABSTRACT FROM AUTHOR]

The spatial heterogeneity and temporal tendency of snow avalanche (hereafter called avalanche) activities are responses to variations in the inducing environment under climate warming and epitomize the repercussions of the global cryosphere on climate warming. This paper focuses on channeled avalanches in the marine snow climate region of the Parlung Tsangpo catchment in southeast Tibet as an example. Through field investigations, we identify the spatial extents of avalanche paths, while historical avalanche flow paths from the past 35 years (1986/1987–2021/2022) within these paths are interpreted using Landsat optical images. Statistical analysis is then employed to derive spatial heterogeneity and temporal tendencies within and between years. The results indicate that the runout altitudes of historical avalanches primarily range from 3468 m to 4051 m, with average flow directions predominantly following the northwest, north and northeast directions. Avalanche activity peaks between February and April, with longer runout distances observed during this period. Regarding interannual regularity, the evolution of the runout distance, runout altitude, and height difference of avalanche flow paths over the past 35 years demonstrates a cyclic evolution akin to a sine function. Additionally, a moderate correlation between the interannual variation in historical avalanche activity intensity and the Southern Oscillation Index was observed. These findings strengthen the understanding of the temporal evolutionary pattern of avalanches in response to climate warming, providing valuable insights into the channeled avalanche occurrences in the maritime snow climate of southeastern Tibet. • Peak avalanche activity occurs between February and April, with March showing the highest activity. • Spring avalanches runout farther and reach lower elevations than do winter avalanches. • The historical evolution of avalanche activity demonstrates a cyclic evolution akin to a sine function. • A moderate correlation was observed between the historical avalanche activity and the Southern Oscillation. [ABSTRACT FROM AUTHOR]

Studying ice deformation starting from crystal scale can provide insight into the microscopic mechanisms of ice deformation. In this paper, a crystal plasticity constitutive model of ice considering the dislocation slip mechanism and grain-size dependence was implemented within the finite element framework, and a modeling approach starting from ice single crystals based on the crystal plasticity finite element method (CPFEM) was proposed to study the elastic-viscoplastic deformation of polycrystalline ice samples. Finite element models of ice single crystals and columnar-grained polycrystalline ice characterizing the microstructure were established successively, and the proposed method was validated by comparing the uniaxial compression prediction results of ice single crystals and columnar-grained polycrystalline ice with the existing experimental data. Finally, the microscopic mechanism of plastic heterogeneous deformation of columnar-grained polycrystalline ice under constant strain rate compression conditions was analyzed. The results indicate that the modeling approach from ice single crystals to polycrystalline ice samples based on CPFEM can reasonably describe the mechanical properties of ice deformation. The deformation of columnar-grained polycrystalline ice globally exhibits apparent slip bands around 30° - 60° relative to the loading direction and locally presents intragranular localization bands parallel or perpendicular to the C -axis. This plastic heterogeneous deformation phenomenon is related to the elastic-viscoplastic anisotropy of ice single crystals and the interaction of neighboring grains at grain boundaries (GBs). • A modeling approach starting from ice single crystals based on CPFEM is proposed to study polycrystalline ice deformation. • Both the dislocation slip mechanism and the grain size-dependent effect are included in the crystal plasticity model. • The numerical method is validated through comparison with the test results of ice single crystals and polycrystalline ice. • The microscopic mechanism of plastic heterogeneous deformation of columnar-grained polycrystalline ice is obtained. [ABSTRACT FROM AUTHOR]

The low temperature and high humidity regions are prone to freezing rain during winter, causing the formation of icicles on the surface of the stayed-cable cylindrical structure. When dislodged by gravity and wind, these icicles may fall and significantly impede the normal movement of vehicles, posing a danger to pedestrians. In this paper, a new organic positive temperature coefficient (PTC) electrothermal film with a Curie temperature of 1 °C is developed by mixing 107 methyl room temperature vulcanized silicone rubber, acetylene black and n-tetradecane through continuous stirring. Subsequently, a numerical simulation of the anti-icing model for the stayed-cable cylindrical structure is established based on the resistivity-temperature characteristics of the new organic PTC electrothermal film. The analysis include variations in the critical anti-icing power of the stayed-cable cylindrical structure with different diameters, horizontal angles, wind speeds and environmental temperatures are analyzed. Finally, the anti-icing experiments are conducted under natural conditions using the stayed-cable cylindrical structure covered with the PTC electrothermal film. The results of the numerical simulation are compared with the natural experimental results, showing a relative error within 3%. This indicates that the anti-icing model of the stayed-cable cylindrical structure is appropriate. The findings of this work provides a theoretical and experimental basis for the subsequent design of an anti-icing device on the basis of PTC electrothermal film. • The PTC electrothermal film with a Curie temperature of 1 °C. • Establish the anti-icing model of the stayed-cable cylindrical structure. • Verify the anti-icing model by natural experiments. [ABSTRACT FROM AUTHOR]

Frame beam-anchor geotechnical structures are increasingly utilized to reinforce slopes in earthquake prone areas. Their dynamic responses have been thoroughly explored. However, the influence of seasonal variation in seasonally frozen regions has been largely ignored. This paper investigates the seismic response of slopes reinforced with anchored frame beams, considering the combined effects of seasonal change and earthquakes. This is achieved through a series of shaking table tests and numerical simulations. The findings reveal that the seismic responses, including acceleration response and displacement response, are more pronounced in the warm season than in the cold season. Conversely, the total axial force of the anchors and the bending moment of the frame columns are greater in the cold season. During the warm season, the frame-anchor slope support system exhibits "high-frequency filtering and low-frequency amplification", while the spectral characteristics in the cold season are reversed. Thus, in the seismic design of such systems in seasonally frozen regions, it is crucial to consider slope deformation in the warm season to prevent damage from excessive acceleration or displacement. Additionally, the internal forces of the anchor frame structure must be checked in the cold season to avoid mechanical failures due to the combined impact of earthquakes and freezing effects. These insights offer valuable recommendations for improving the seismic design of frame beam-anchor structures in seasonally frozen regions and pave the way for further research on the seismic responses of various retaining slope structures in these areas. • Seismic performance of the seasonal frozen slope reinforced with the anchored frame beam was investigated. • Acceleration and displacement response are more pronounced in the warm season. • Total axial force of the anchors and the bending moment of the frame columns are greater in the cold season. • Acceleration spectral response in the warm season exhibits "high frequency filtered and low frequency amplified". [ABSTRACT FROM AUTHOR]

The main danger to which backcountry skiers are exposed are dry slab avalanches triggered by skiers themselves. In this paper we present a new probabilistic method to assess the avalanche risk when planning a ski tour: SLABS (S creening the L ikelihood of A valanches on B ackcountry S ki tours). The SLABS method is the first fully statistically derived probabilistic method for backcountry skiing. We used a data set with GPS (Global Positioning System) tracks of backcountry ski tours (57.8 thousand km) and a data set of 1250 accidents recorded in Switzerland during the last 20 winter seasons. A GAM (Generalised Additive Model) with binomial link discriminating between accidents and non-accidents was fitted to these data. As predictors the model uses a non-linear relation with the slope angle, and a linear relation with the danger level, the elevation and the aspect. Conditions with elevated and high risk were defined such that the accident prevention rate is 80% and 60%, respectively. A comparison of the SLABS method with the Graphical Reduction Method (GRM), the Professional Reduction Method (PRM) and the Quantitative Reduction Method (QRM) shows that it offers more freedom of movement for a given accident prevention rate. It is the first time that probabilistic methods are compared in terms of their trade-off between accident prevention and freedom of movement. Because the SLABS method is not suited for mental arithmetic it is implemented in the website www.skitourenguru.ch. This website evaluates on a daily basis the avalanche risk along thousands of backcountry tours throughout the Alps to help skiers plan their next tour. For a single slope the risk assessment of SLABS provides a starting point that has to be supplemented with local observations. [Display omitted] • A Generalised Additive Model was fitted to both backcountry accident and travel data. • A new probabilistic method for avalanche risk during backcountry skiing was developed. • Maximum slope angle, danger level, elevation and aspect are combined in a risk score. • The trade-off between prevention and freedom is better than for existing methods. • Implemented in www.skitourenguru.ch the new method helps skiers plan their tours. [ABSTRACT FROM AUTHOR]

This paper presents the establishment of a macro-mesoscopic constitutive model based on poromechanics for investigating the mechanics of warm frozen soil. The elastic parameters of warm frozen soil are influenced by the ice content variations during the loading process, considering the pressure melting characteristic of warm frozen soil. Through the integration of poromechanics and mesomechanics, a macro-mesoscopic constitutive model incorporating the pressure melting effect is developed to characterize the mechanical properties of warm frozen soil. The proposed model establishes a relationship between the elastic modulus at the mesoscopic and macroscopic scales of warm frozen soil.To validate the model, a comparison is made between the model predictions and experimental data obtained from warm frozen silt. The results demonstrate that the model effectively captures significant mechanical performance of warm frozen soil, including strain soft and dilatancy phenomena under various confining pressure conditions. Furthermore, the proposed model enables the prediction of freezing temperature, unfrozen water saturation, unfrozen water pressure, ice pressure, and porosity changes in warm frozen silt samples during the loading process. • A new constitutive model for warm frozen soil is proposed at mesoscopic scale. • The model can model the mechanical behaviors of warm frozen soil well. • The model can predict ice pressure and water pressure within warm frozen soil. [ABSTRACT FROM AUTHOR]

The warming and melting of permafrost due to climate warming pose a considerable threat to the integrity of the Pan Arctic building, thus jeopardizing sustainable development. The increase in ambient temperature in permafrost areas will cause deterioration in the bearing capacity of building pile foundations. Considering the continuous deepening of the active layer (z a), the present paper used small-scale physical modeling to investigate the potential variation of bearing capacity and load transfer mechanism of pile foundations under the scenario of continuous degradation of permafrost. The ultimate bearing capacity of a single pile and the undrained shear strength of the ground under different z a are estimated by cone penetration tests. In the static load test of single piles, the axial load-settlement, axial force of pile shaft, and earth pressure at the pile tip are measured. The results show that the rise in ground temperature and the deepening of the z a shorten the elastic and elastic-plastic stages of the load-displacement curve, resulting in a gradual decline in the bearing capacity of a single pile. The pile-soil interface temperature is always higher than the adjacent ground temperature at the same depth. Adfreezing force of the pile-soil interface decreases due to the increase in ground temperature and water content. With the deepening of z a , the peak point of the shaft resistance decreases from −30 cm to −60 cm under the ultimate state. Meanwhile, with more axial load transfer along the pile shaft to the pile tip, the share ratio of pile tip resistance to ultimate stress gradually increases. In addition, the temperature rise of frozen soil at the pile tip accelerates the settling rate of the pile, which eventually causes the pile foundation failure. • Climate warming threatens buildings in the Pan Arctic permafrost regions. • Tests are performed to investigate the bearing capacity of building pile. • Revealed the evolution law of pile bearing capacity during permafrost degradation. • The pile adfreezing force decreases with increasing ground temperature. [ABSTRACT FROM AUTHOR]

Sea-spray icing resulting from sea spray droplets accreting on exposed surfaces poses a significant safety concern for vessels and marine structures operating in cold climate regions. One of the key parameters determining the amount of ice accretion is the quantity of incoming sea spray, which eventually comes in contact with the structure in the presence of brine film freezing temperature. Hence, to develop marine icing estimation models, researchers have been inclined towards conducting field measurements to acquire data on sea spray and its key characteristics, such as liquid water content (LWC, mass of spray water per unit volume of air), spray frequency and duration, and droplet size distribution. This paper provides a critical review of various techniques used by researchers for sea spray field measurements. By employing Computational Fluid Dynamics (CFD) simulation, this paper also evaluates the performance of instruments for measuring sea-spray flux employed in such field campaigns. Design issues and potential areas for improvement are identified and discussed, based on which further recommendations for improvement of sea spray data collection are provided. The study provides valuable insights for researchers planning field measurement expeditions and exploring viable options to design an efficient system for collecting sea spray data. • Field measurements for collecting sea-spray data play a crucial role in developing marine icing estimation models. • The paper critically reviews and analyses various techniques used for sea-spray field measurements. • Computational Fluid Dynamics (CFD) simulation is used to assess the performance of sea-spray flux measurement instruments. • Design issues and potential improvements in data collection methods are identified and discussed. • The study offers valuable insights for researchers planning field measurement expeditions. [ABSTRACT FROM AUTHOR]

Precise evaluation of the frost heaving force and surrounding rock plastic zone is an important basis of the prevention of freezing damage in cold-region tunnels. The temperature gradient along the radial direction of cold-region tunnels surrounding rock results in the dual non-uniform frost heaving of surrounding rock, namely, the gradual change of frost heave ratio along the radial direction and the unequal frost heaving deformation in the circumferential and radial directions. A new elastoplastic solution of tunnel frost heaving force considering double non-uniform frost heave and intermediate principal stress was derived based on the elastoplastic mechanics theory, thick-cylinder theory, and unified strength theory to better guide the frost resistance design of tunnels in cold regions. The rationality and advantages of the unified plastic solution of tunnel frost heaving force were verified by model tests and engineering examples. Results showed that the theoretical calculation value of frost heaving force was in good agreement with the measured value. When the gradual change in the frost heave ratio of surrounding rock in the radial direction was ignored, the frost heaving force and radius of the surrounding rock plastic zone were large and conservative. The solution in this paper can accurately evaluate the tunnel frost heaving force and surrounding rock plastic zone. Finally, this paper studies the influences of intermediate principal stress coefficient, the frost heaving coefficient of unit temperature of frozen surrounding rock, non-uniform frost heaving coefficient in different directions, and maximum freezing depth on the evolutionary law of frost heaving force and plastic zone of cold-region tunnels are studied. • A dual non-uniform frost heaving model of cold region tunnels is proposed. • Use temperature gradient to describe the non-uniform frost heave of the surrounding rock. • An elasto-plastic solution for frost heave force based on dual non-uniform frost heave is derived. • Theoretical solutions, model test results and engineering tunnel cases were compared. [ABSTRACT FROM AUTHOR]

This paper experimentally investigates the effect of increasing ice thickness at a heater's edge on the thermal energy required to de-ice ice at the leading's edge. A correlation between ice thickness at the stagnation line and ice thickness at the heater edge is developed for the leading edge of a cylinder surface. An experimental approach is used to investigate whether the increase in ice thickness at the heater's edge is linked to the increase in ice thickness at the stagnation line. The de-icing investigation shows that as ice thickness at the heater's edge grows, the de-icing duration significantly increases. The results of this paper suggest that employing a correlation between the ice thickness at both the stagnation line and the heater's edge can help reduce the thermal energy required to remove ice from the leading edge of an airfoil or cylindrical surface. • Defining the ice thickness relationship at the stagnation line and heater edge for cylindrical ice accumulation. • Examining the impact of ice thickness at the heater edge on the thermal energy required for de-icing. • Using imaging techniques to measure accumulated ice on a cylindrical surface. • Using thermal imaging to analyze the behavior of ice during the de-icing process. [ABSTRACT FROM AUTHOR]

It is important to understand the properties and parameters of ice growth models, to enable reliable assessment of the impact ice may have on facilities or to ship navigation. To improve the understanding of the different models, the theoretical formulations for ice growth are investigated and calculated results compared with laboratory and full-scale measurement data. The paper describes the ice growth models for level sea ice and how these are applied in brash ice consolidation modelling. In particular, analysis is made to account for modelling of snow cover in level ice growth models, and subsequently also salinity, porosity and the atmospheric boundary including wind effect in brash ice models. The paper presents an overview of laboratory tests and results for both level ice and brash ice. Also models for level ice growth for the case of snow cover are derived and compared with thetest results. Specifically, inclusion of snow thickness in the growth model presents some practical difficulties, as the thickness of snow cover is often not known a priori, and comparison between calculated level ice thickness and measurements suggests that a good assumption in predictive models is to assume the snow cover thickness to be proportional to level ice thickness. Further, it was observed that the wind influences much the heat transfer to atmosphere, which is not zero at the zero wind speed, a value for the heat transfer coefficient to atmosphere is derived based on laboratory tests. The findings from these analyses provide an improved understanding of the ice growth and consolidation process which can be incorporated into modelling techniques for marine design and operations. • Models for brash ice growth and the parameters therein • Laboratory tests on brash ice growth, effect of porosity, salinity and wind • Values for atmospheric heat transfer coefficient with and without wind [ABSTRACT FROM AUTHOR]

Overhead lines in the United States are currently designed based on both deterministic and probabilistic loading concepts for ice and wind. These load cases are specified in the National Electrical Safety Code (NESC) (Institute of Electrical and Electronics Engineers, Inc. (IEEE), 2023). The deterministic loads for the continental United States are based on three loading districts: light, medium, and heavy, and the corresponding loads based on the specified weather criteria are to be used with specified structural load factors. In practice, the factored deterministic loads often control the design of a structure compared to the probabilistic loads which apply a load factor of 1.0. Furthermore, the deterministic loads are not associated with a Mean Recurrence Interval (MRI), thereby making the assessment of the reliability index cumbersome for structures controlled by these loads. A method to determine an equivalent MRI for these deterministic loads is presented, which involves associating the factored deterministic loads with a probability of exceedance based on location for ice and wind loads. The method is applied to a 230 kV transmission line including seven structure types and line angles, and for 26 locations across the continental United States, and a comparison of the equivalent MRI based on the deterministic loads is made to the probabilistic loads. Trends are presented which illustrate that the resulting equivalent MRI vary significantly among location and structure types. The findings highlight that different structure types of the same transmission line are associated with a wide range of equivalent MRI. Discussion is provided on the trends observed in case study and the inconsistency in structural reliability that could result from the application of deterministic ice and wind load criteria in NESC Rule 250B. It is not the intent of this paper to state what design MRIs are needed to ensure adequate reliability. The intent of this paper is to determine what range of structural equivalent MRIs overhead lines in the United States are currently designed to withstand. • For transmission line structures designed in the United States, what sort of probabilistic weather conditions are these lines designed to resist? • The structural design for many structure types is controlled by the deterministic load case NESC Rule 250B. Since this load case is deterministic the likelihood of exceeding this load (MRI) is not available. • The proposed method provides a way to determine the equivalent mean recurrence intervals (MRIs) for the deterministic structural load case NESC Rule 250B. • The results show that the equivalent MRIs highly vary based upon location. • The results show that structures with small line angles have lower MRIs and structures with large line angles have higher equivalent MRIs. Tangent structures exhibit a median equivalent MRI of approximately 100-yrs. Deadend structures exhibit a median equivalent MRI of approximately 1000-yrs. [ABSTRACT FROM AUTHOR]

Ice and snow shedding events on cable-supported bridges around the world have become more frequent in recent years. Although they pose a risk to bridge users and lead to lengthy bridge closures, the research so far has focused mainly on the development of various countermeasures and the aerodynamic behaviour of cables with ice or snow accretions. In this paper, a wind tunnel investigation aimed at simulating atmospheric conditions to reproduce natural accretion and shedding of ice and snow from different bridge cable surfaces is presented. The experimental investigation was carried out at two different climatic wind tunnel facilities and involved the use of two different solar simulators to simulate the effect of solar radiation on the melting and shedding process. It was found that both the colour of the cable surface and the surface modifications had a significant influence on the melting and shedding of ice and snow. Whilst the cable colour affected the heating rate of the cable surface and governed the shedding rate of smooth cable sections, the use of surface modifications such as steel wire mesh was more effective in retaining the accretions for longer and breaking them into smaller pieces. The analysis further revealed how the non-uniform heat transfer distribution around the cables affects the surface temperatures at specific locations and how much solar irradiance is approximately transmitted through the accretions onto the cable surface. These findings improve the fundamental understanding of ice shedding from bridge cables and demonstrate the performance benefits of cable surface modifications in terms of risk mitigation for bridge users. • Ice shedding was studied in two different wind tunnels with solar simulators. • Ice and snow melting rate increased on darker bridge cable sheaths. • Surface modifications impact ice shedding performance more than sheath colour. • Wire mesh on bridge cables can reduce ice shedding risk significantly. [ABSTRACT FROM AUTHOR]

In winter, cold air flowing into tunnels undergoes heat exchange with the surrounding rock and lining, rendering frost protection a critical concern. In this paper, a practical procedure for integrating the FEM–CFD coupled method into probabilistic analysis is presented for determining the thermal insulation length demand of tunnels in cold regions, in which uncertainties in the air temperature and wind speed are considered. The results indicate that with ventilation implemented in the coldest month, tunnel temperatures gradually rise along the longitudinal direction, exhibiting a distinct temperature variation near the entrance. Based on the numerical simulation results obtained with 100 air temperature and wind speed samples, generated using the Monte Carlo method, the thermal insulation length demand of the tunnel ranges from 1000 to 1500 m, showing a distribution that follows the characteristics of a normal distribution. Additionally, a corresponding surrogate model is developed, and a thermal insulation failure probability model is proposed to analyze the sensitivity of meteorological parameters, revealing that the air temperature is the primary factor influencing the thermal insulation length demand. The findings of this research provide novel insights for the engineering community in designing resilient and sustainable tunnels in cold regions, mitigating the potential risks associated with freezing events and ensuring safe and efficient transportation infrastructure. • Probabilistic models for air temperature and wind speed were proposed. • Uncertainties of air temperature and wind speed affect thermal insulation length. • A surrogate model of the thermal insulation length demand was developed. • An analysis of the thermal insulation failure probability was conducted. [ABSTRACT FROM AUTHOR]

Rock-ice avalanches have high mobility and enormous destructive potential. However, the friction behaviors and flow resistance during the transition of flow regimes of the rock-ice avalanche remains an unsolved problem. Based on a series of measurements of normal, shear stress and pore water pressure at the rotating drum in a temperature-controllable laboratory, we quantify the influence of the ice content, particle size, drum velocity, and meltwater on the friction behaviors. The findings reveal that ice acts as a low-friction particle, leading to a significant reduction in frictional resistance of both particle-particle and particle-base. Furthermore, meltwater lubricates the particles and provides buoyancy, which also increases the mobility of the rock-ice avalanche. In addition, the augmentation of flow resistance is attributed to the increased particle size and drum velocity, thereby intensifying shear motion. In order to propose an unify theoretical model to calculate the flow resistance of rock-ice avalanche in various flow regimes. A heuristic model that relies on the extended dynamics theory is modified and can be well described the flow resistance of the tests involved in this paper. This study in the friction behaviors and flow resistance depending on the internal/external factors may be considered in hazard assessments of rock-ice avalanches in cold high-mountain regions. • Exploring key factors' impact on friction behavior of rock-ice avalanche. • The flow regimes dominate the flow resistance of rock-ice avalanche. • Proposing a unified model to calculating flow resistance for various regimes. [ABSTRACT FROM AUTHOR]

The principle of effective stress is widely recognized as the cornerstone of soil mechanics, with its application extending beyond soils to other porous materials such as rocks and concrete. In recent decades, there has been a significant surge in scientific research and engineering practice in cold regions, where the classical framework of effective stress in soil mechanics is frequently invoked. However, there is no consensus either on mathematical expressions or especially on the physical nature of effective stress in a soil when ice is involved. This paper starts from Terzaghi's principle of effective stress for saturated soils, and subsequently Bishop's work for unsaturated soils and the Clapeyron equation for phase change are introduced as the basis for further discussions. Focus is laid on a comprehensive analysis on formulas for effective stress with respect to cold regions geotechnical engineering. Two categories are classified, in which the effective stress is considered to be undertaken by soil skeleton only and by soil skeleton-ice system together, respectively. They may generate calculated results that can efficiently interpret experiments or observations, while both are rather speculative and faced with major challenges. Controversies on effective stress for unfrozen soils are analyzed with respect to cold regions geotechnical engineering. It is recognized hardly possible to develop a mechanism-based principle of effective stress based on the current understandings, while it is questionable to develop it based on that for unfrozen soils. Two potential approaches are suggested that might be applicable for cold regions geotechnical engineering. • Effective stress in research of cold regions geotechnical engineering is inspected. • Current formulas can be categorized in two groups based on stress sharing. • Extending original principle of effective stress to soils with ice is challenging. • Two potential approaches are suggested for cold regions geotechnical engineering. [ABSTRACT FROM AUTHOR]

The high-speed and long-distance sliding characteristics of large-scale rock-ice avalanches usually make them a catastrophic event, which seriously threatens the safety of human beings and infrastructure. Obviously, apart from the lubrication of ice and water, the fragmentation of particles in the slip zone is also an important contribution to the hypermobility of rock-ice avalanches. Up to now, existing researches have not taken into account the impact of particle breakage on rock-ice landslides. In this paper, a thermal-hydro-mechanical (THM) model for the high-speed rock-ice avalanches is developed, which mainly considers the particle breakage due to sliding shear deformation and the ice melting caused by frictional heat. The results of the model analysis applied to the Chamoli avalanche indicate that particle fragmentation has a significant effect on landslide sliding. When the particle breakage is considered, the simulated velocity and displacement of landslide are closer to the existing research results. Both thermal pressurization and particle crushing are two important mechanisms that lead to a high-speed sliding of rock-ice landslide, and these two mechanisms affect each other. It is demonstrated from a set of sensitivity analyses that the initial grain size distribution, fractal dimension and the thickness of the slide mass have clear impacts on the evolution of the granular crushing index, which thus affects the characteristics of the landslide eventually. In particular, the sensitivity analysis of the slide thickness once again demonstrates the importance of considering particle fragmentation in the analysis of landslide sliding. • A thermal-hydro-mechanical (THM) model for the high-speed rock-ice avalanches is developed. • The influence of particle fragmentation and thermal pressurization on the sliding of rock-ice landslides is analyzed. • A parametric sensitivity analysis of particle size, fractal dimension, and slide thickness on landslide sliding is performed. [ABSTRACT FROM AUTHOR]

The transport of ice particles beneath a stable ice cover (referred to as cover load transport), and the processes leading to ice deposition and erosion are highly dynamic and complex. Based on the strong analogous relationship between bed load and cover load transport processes, knowledge from bed load transport research can be used when developing experiments for cover load transport processes. This paper presents a detailed experimental study of cover load transport rate in a laboratory flume with simulated ice particles and a simulated ice cover. The effect of the particle shape and size on cover load transport rate is quantified using the buoyant velocity and its velocity coefficient. The critical dimensionless flow strength is identified as an important parameter which determines the incipient motion of the under cover ice particles, and was calculated using hydraulic measurements obtained through laboratory experiments. A new cover load transport formula is introduced based on regression analysis of experimental data for a wide range of dimensionless flow strength conditions. The impact of incoming ice supply rate on the under cover ice transport rate was also investigated by altering the ice supply rate to the flume. A control volume analysis of ice discharge underneath the ice cover is used as the approach to quantify the dimensionless ice transport rate at different sections of the flume. The concept of equilibrium ice transport rate is introduced based on the experimental observations with variable incoming ice supply rates. The experimental observations on the impact of incoming ice supply were supported by an analysis of field data from Hequ Reach, China (Sun et al., 1986; Wang, 1992). The introduction of a cover load transport formula developed exclusively with simulated ice particles that have similar physical properties to ice forming in a natural environment, and the discussion on equilibrium ice transport rate are important contributions to advance the present understanding on under cover ice transport processes. • Cover load formula using simulated ice with similar properties as ice in the natural environment. • Equilibrium ice transport concept introduced based on variable ice supply rates. • Critical dimensionless flow strength determines the incipient motion. • Relevant to further studies related to numerical modeling of ice transport. [ABSTRACT FROM AUTHOR]

Freeze–thaw (FT) alternation can severely affect the properties of fine–grained soils, often leading to the failure of foundation backfill projects, such as open canals and roads in cold regions. To address these problems, a water–soluble anionic polyacrylamide (APAM) was used to improve the properties of fine–grained soils, particularly silty clay. This study aims to analyze the effects of the APAM polymer on the physico–mechanical and microstructural properties of silty clay under both unfrozen and FT cycles. For this purpose, different addition dosages and FT cycle numbers were determined, and then a series of zeta potential, thermal conductivity, permeability, triaxial compression, and scanning electron microscopy (SEM) tests were conducted on the soil samples. Additionally, a unidirectional freezing test was constructed to investigate the coupled thermo–hydro–mechanical processes of APAM–treated soil samples. The results showed that the addition of the APAM polymer significantly enhanced the macroscopic engineering properties and microstructural characteristics of silty clay. This improvement was attributed to the charge neutralization, adsorption bridging effect, and hydrophobic interaction provided by the APAM polymer. However, all the soil samples showed a significant deterioration in their engineering properties during FT cycles, especially after the third FT cycle. It was notable that APAM–treated soil samples were superior to the untreated sample in terms of FT resistance. During the unidirectional freezing process, the pore water migrated from the unfrozen zone towards the freezing front due to the temperature gradient. The treated sample's pore water migration volume was considerably lower than that of the untreated sample, resulting in a 55.25% reduction in total frost heave when the APAM dosage was 0.30%. The findings of this paper may be utilized to mitigate the risk of frost damage to foundation backfill projects in cold regions, as well as to get a better understanding of the stabilization mechanism of the eco–friendly APAM polymer. • Eco–friendly APAM polymer was used to improve the properties of silty clay. • Effect of APAM polymer on the FT resistance of silty clay was assessed. • Thermo–hydro–mechanical processes of treated silty clay samples were investigated. • APAM polymer significantly improved the FT resistance of silty clay. [ABSTRACT FROM AUTHOR]

In cold regions, freeze-thaw induced damage to concrete is among the most severe issues that affect structures, leading to shortened lifespans of concrete-related structures and causing substantial economic losses. Therefore, it is crucial to enhance the freeze-thaw durability in cold regions. To achieve this aim, we combined n-tetradecane (C 14) and expanded perlite (EP) to produce a composite phase change material (EPC 14) with cement encapsulation. The essential material performances of the EPC 14 were characterized through a series of physical and chemical tests. The measurement results show that the EPC 14 possesses an appropriate phase change temperature, chemical stability, and mechanical reliability. Hence, it is an excellent candidate material for producing phase change concrete. In this study, we selected five volumetric replacement ratios of the EPC 14 to fine aggregates (0%, 10%, 20%, 30%, and 40%) to prepare the phase change concretes (PCC-EPC 14 s). After these PCC-EPC 14 s samples were properly cured and then underwent 0, 50, 100, and 200 freeze-thaw cycles (FTCs), their physical and mechanical properties were systematically measured through nuclear magnetic resonance (NMR), resonance frequency tests, and uniaxial compression tests. The comprehensive measurement results demonstrate that at 0 FTCs, a higher content of the EPC 14 results in larger porosity in the PCC-EPC 14 s, leading to lower compressive strength and relative dynamic modulus of elasticity. However, after 200 FTCs, the PCC-EPC 14 (20%) exhibits the highest compressive strength and relative dynamic modulus of elasticity, whereas the PCC-EPC 14 (0%) exhibits the lowest values for both of these properties. Furthermore, fractal theory was employed to analyze the mechanical properties of the PCC-EPC 14 s from a microscopic perspective. The results indicate that the PCC-EPC 14 (20%) exhibits the largest NMR fractal dimension after 200 FTCs, signifying the least complexity and integration in its pore structure. In comparison to the PCC-EPC 14 s (0%, 10%, 30%, 40%), it is less prone to developing damage cracks under compression. In conclusion, we advise using the PCC-EPC 14 (20%) in practical construction projects. The PCC-EPC 14 s prepared in this paper offer valuable insights for enhancing the freeze-thaw durability of concrete in cold regions. • A new composite phase change concrete was produced and experimentally investigated. • An optimal content of the phase change material was selected out. • The phase change concrete has excellent freeze-thaw durability. [ABSTRACT FROM AUTHOR]

In cold and snowy regions, roof slopes can affect the snow distribution on the gable roof. The finite area element (FAE) method is modified by considering the effect of the snow transport rate, the developmental law of snow transport and the saturated transport distance on the calculation of drifting snow load in this paper. Saltation and suspension of snow transport are also considered respectively in the process of modification. Then, based on the modified FAE method and computational fluid dynamics (CFD), the influence of roof slopes (10°, 20°, 30° and 40°) on the gable roof snow distribution is studied. Meanwhile, for compare the simulation results of the modified FAE method with different combinations of the snow transport rate, the developmental law of snow transport and the saturated transport distance, the test of wind-blown snow redistribution is completed in the wind tunnel using the substitute particles (silica sand) on the scaled gable roofs. The results show that when the saturated transport distance of snow is 210 m, the modified FAE method can reproduce the snowdrift phenomenon on the gable roof more reasonably if adopting the snow transport rate proposed by Owen (1964) and the developmental law of snow transport suggested by O'Rourke et al. (2005) at the same time. Through CFD simulation, it's discovered that the distribution of flow field around the gable roof and friction velocity on snow surface change noticeably with roof slopes, resulting in the increase of the upwind erosion flux and the leeward deposition flux with the incoming wind speed and the roof slope. In addition, when the incoming wind speed remains unchanged, simulation results using the modified FAE method show that the larger slope of the gable roof, the more likely it is to cause the uneven distribution of snow load on the windward and leeward roofs. Moreover, fresh snow is more likely to cause the uneven distribution of snow load on gable roofs than aged snow through analysis sensitivity of the threshold friction velocity. • The FAE method is modified based on the development process of snow transport and CFD simulation. • The modified FAE method is validated through wind tunnel tests. • The snow distribution on gable roofs is simulated using the modified FAE method. • The influence of slope on the snowdrift load coefficient is analyzed though the characteristics of snow distribution. [ABSTRACT FROM AUTHOR]

Natural weak plane of rock is a great threat to the stability of the rock project in cold areas due to the freeze-thaw environment. However, the effect of both weak plane and freeze-thaw cycles is rarely considered. This paper investigated the deterioration mechanism of granite with a natural single weak surface after 0, 20, 40, and 60freezing-thawing cycles. Experimental results show that as the number of freeze-thaw cycles increased, the peak strength of samples decreased while the axial strain gradually increased. The weak plane angle has a significant impact on the sample strength. The strength and elastic modulus changed in a 'U' shape with the increase of weak plane angle. The samples exhibited a shift from brittle failure to ductile failure with the increase of freeze-thaw cycles. A theoretical model for predicting rock strength is proposed with consideration of weak plane and freeze-thaw effects by combining the single weak plane theory with the decay function. The proposed model is verified by experimental data. The predicted values based on the proposed model match well with experimental data. Samples with lower porosity but higher tensile strength and elastic modulus have larger frost resistance. The research results can provide a scientific basis for the safety assessment of geotechnical engineering in cold regions. • Deterioration mechanism of granite with a natural single weak surface by freeze-thaw. • Strength and elastic modulus changed in a U shape with the increase of weak plane angle. • Prediction model for rock strength with consideration of weak plane and freeze-thaw. [ABSTRACT FROM AUTHOR]

Hydropower resources have been developed to the cold regions in the west of China recently, wherein the dam will be subjected to high frequency of repeated freeze-thaw action during the construction process in winter, and thus will cause safety and stability problems of these projects. According to the actual construction situations of Lianghekou hydropower station located in Sichuan Province, one-side freezing and two-side thawing tests of unsaturated core-wall soil samples in a closed system are carried out, and the evolution of temperature, water and displacement as well as their interaction are tested and analyzed. The results show that with the increasing of freeze-thaw cycles, water migration results in a decrease of water content in the unfrozen zone and an increase in the frozen zone, and the water concentration area is formed in the soil column. Simultaneously, a deeper freezing depth accompanied with a shorter thawing duration after 10 freeze-thaw cycles is observed through the temperature field results, whereas a steady fluctuation of the deformation field is showed after the 7th freeze-thaw cycle. Moreover, based on the test results and exiting researches, a thermo-hydro-mechanical coupling model for unsaturated soils subjected to cyclic freeze-thaw action is proposed, in which both the permeability and compressibility are inextricably related to the void ratio, and vary in different calculated areas. Additionally, the effects of number of cycles on initial conditions and model parameters are also considered. Comparisons with the experimental data demonstrate the validity and adaptability of the proposed model in describing the freeze-thaw process of unsaturated soil. Through the combination of experiments and numerical simulation, the freeze-thaw process can be more clearly understood, and related engineering problems can be predicted with the help of the mathematical model in this paper. • One-side freezing and two-side thawing tests of unsaturated soil are carried out. • A thermo-hydro-mechanical coupling model in freeze-thaw process is proposed. • The thermo-hydro-mechanical coupling mechanism is revealed by simulations. [ABSTRACT FROM AUTHOR]

Temperature changes may cause irregular soil uplift or thawing settlements in frozen soil areas, potentially affecting the safe operation of High-Speed Railways (HSR). Analyzing and predicting these deformation characteristics is thus critical. However, the conventional forecasting and analysis techniques rarely considered factors such as dynamic parameter variations, uncertainties, and measurement errors, which hinder accurate regional scale forecasting. To bridge this gap, this paper introduces a novel time-series coupling method, which integrates post-processing deformation from Interferometric Synthetic Aperture Radar (InSAR) with a frost heave model (FHM), facilitated by the ensemble Kalman filter (EnKF) assimilation algorithm. We obtained deformation observations along the HSR using Persistent Scatterer InSAR (PS-InSAR) technology in combination with time-series post-processing techniques. Considering the causative factors for deformation, we structured the FHM. By integrating FHM with observational data using the EnKF algorithm achieved an efficient upgrade of the posterior distribution of model parameters. This integration significantly improves the predictive accuracy, it facilitates an efficient update to the posterior distribution of model parameters, leading to enhanced prediction accuracy of our model. Our experimental results indicate that the effectiveness of this approach, with observational data assimilation into FHM reducing the average Root Mean Square Error (RMSE) to a mere 0.247 mm. Concurrently, both the Normalized Reduction Error Index (NER) and the Assimilation Efficiency Factor (EFF) values surpassed 0.60 and 0.84 respectively. These underlines signify a successful update of our model parameters, which in turn elevates the accuracy of future deformation predictions, thereby promising safer railway operations. • a time series coupling method based on data assimilation is proposed by considering the triggering factors of deformation. [ABSTRACT FROM AUTHOR]

Ice accretion on various onshore and offshore infrastructures imparts hazardous effects sometimes beyond repair, which may be life-threatening. Therefore, it has become necessary to look for ways to detect and mitigate ice. Some ice mitigation techniques have been tested or in use in aviation and railway sectors, however, their applicability to other sectors/systems is still in the research phase. To make such systems autonomous, ice protection systems need to be accompanied by reliable ice detection systems, which include electronic, mechatronics, mechanical, and optical techniques. Comparing the benefits and limitations of all available methodologies, Infrared Thermography (IRT) appears to be one of the useful, non-destructive, and emerging techniques as it offers wide area monitoring instead of just point-based ice monitoring. This paper reviews the applications of IRT in the field of icing on various subject areas to provide valuable insights into the existing development of an intelligent and autonomous ice mitigation system for general applications. [ABSTRACT FROM AUTHOR]

This paper describes BC Hydro's current design practice for determining ice and wind loads on overhead transmission lines based on the reliability-based design principles. Following important issues are discussed and clarified: selection of design reliability levels, prevention of cascading failures, determination of IceWind load case, inclusion of IceOnly load case, consideration of un-equal ice and broken wire load cases, consideration of wet snow and galloping. The BC Hydro standard practice has been developed based on the industry's best practice and BC Hydro's own successful experiences in the past. This paper may serve as a good reference for other utilities in designing their transmission lines. • This paper describes BC Hydro's current design practice for determining ice and wind loads on overhead transmission lines based on the reliability-based design principles. • Following important issues are discussed and clarified: selection of design reliability levels, prevention of cascading failures, determination of IceWind load case, inclusion of IceOnly load case, consideration of un-equal ice and broken wire load cases, consideration of wet snow and galloping. • The BC Hydro standard practice has been developed based on the industry's best practice and BC Hydro's own successful experiences in the past. [ABSTRACT FROM AUTHOR]

With the continuous development of the urban underground space, the depth of the underground structures is also increasing. As a typical soft soil area, the geological environment in Shanghai is very complex and rich in groundwater. Unlike traditional support measures, the artificial ground freezing method can be applied to various complex geological conditions with its unique advantages. In this paper, the distribution of the freezing temperature field and the frost heave deformation for a deep foundation pit constructed by the pile freezing method were studied by the numerical simulation. The distribution of the freezing temperature field in the single freezing hole, the double freezing holes and the single row holes were analyzed, respectively. After the excavation of the deep foundation pit, the temperature fields of straight and corner sections were also studied. The effect of the piles on the distribution of the freezing temperature field and the frost heave deformation of the ground was compared. The research results of this paper can provide a design basis and a reference for the construction of deep foundation pits by the artificial ground freezing. • AGF with row piles was conducted to deep foundation pits. • Freezing temperature field and frost heave of deep foundation pit were studied. • Effect of row piles on temperature field and deformation were analyzed. [ABSTRACT FROM AUTHOR]

Icing losses encountered in a wind farm are very hard to assess as they can vary by a factor of three from year to year. This inter-annual variation is a critical issue from the assessment phase to the operation of wind turbines in cold climate. To mitigate the effects of this issue, a proposed solution is to define an ice index to yield a reference for icing conditions based on historical values. Knowing that icing frequency has an inter-annual variation 5 times greater than the wind speed, the definition of an ice index is long overdue. This paper proposes a simple and accessible method for defining an ice index based on cloud base height measured at a weather station. A similar strategy is already used in the industry for other purposes such as estimating the long-term average icing frequency in icing maps. The novelty of the proposed method lies in the description of the variation in icing frequency rather than its long-term average. The ice index proposed in this paper is shown to be representative of the icing losses in 6 wind farms located in eastern Canada. Moreover, it was also shown that the ice index is strongly correlated to the icing measurements made on wind turbine nacelle. In this paper, the yearly and monthly ice indexes, from September 2007 to December 2021, are shared. These indexes are based on the meteorological data from Valcartier weather station near Quebec City. This definition of an ice index directly responds to a critical need of the wind industry in cold climate, a common reference for icing frequency. Ice indexes could be publicly shared each month in cold climate areas to guide wind farm owners and operators in their decisions and analysis of performances. Such an index could also be used to asses the long-term variation of the ice index and the effect of climate change on icing frequency and impacts on the wind energy production in cold climate. • Definition of an icing frequency index based on publicly available could base height measurements. • Relationship between the ice index and icing losses in six wind farms. • Relationship between the ice index and the meteorological icing frequency measured on a wind turbine nacelle. [ABSTRACT FROM AUTHOR]

This paper presents laboratory data from tests on four fine-grained soils: reconstituted Kaolinite, destructured Bothkennar clay, reconstituted Bothkennar clay, and reconstituted Gault clay. The soil samples were conditioned in an oedometer cell while being subjected to varying numbers of freezing and thawing cycles. The influence of freeze-thaw cycles on key soil parameters, including the hydraulic conductivity, Atterberg limits, compression and swelling index was studied. The experimental results were then compared with the analysis of a previously published database of hydraulic conductivity measurements on fine-grained soils called FG/KSAT-1358. The paper demonstrates that while multiple cycles of freezing and thawing affect some of the studied soil parameters, such as the Atterberg limits and the compression characteristics, the effects on the hydraulic conductivity transformation model parameters, linking the water content ratio to hydraulic conductivity are less apparent. The results are useful for geotechnical and pavement engineers when making assessments of freeze-thaw effects on subgrade materials in cold regions. • New experimental data shows that compression index tends to gradually reduce with multiple freezing and thawing cycles for three soils • For the reconstituted and destructed samples tested, the decrease in compression index due to multiple freezing and thawing cycles is similar to the difference between the two sample states • New experimental data linking water content ratio to hydraulic conductivity for the tested soils exhibits comparable statistical trends with those obtained from analysis of the FG/KSAT-1358 database [ABSTRACT FROM AUTHOR]

Perforated concrete structures are common in engineering, and concrete members can easily experience frost cracking in cold regions. Thus, this paper conducts frost heave tests on perforated concrete, aiming at the problem of the frost heave cracking risk of perforated concrete structures in cold regions. Utilizing the temperature-distribution monitoring method, we obtain the icing behavior and ice-plugging effect along the length direction of a hole in the concrete. Then, the cracking characteristics of concrete with holes under freeze–thaw cycles are mastered by performing rapid freeze–thaw tests on concrete with holes and observing the cracked section. The reason why concrete does not crack immediately under theoretical frost heave force is also revealed. Finally, this paper proposes that hydrophobic filling materials can alleviate the frost heave stress on concrete. The findings of this work reveal the mechanism for the frost cracking of concrete with holes and put forward preventive measures, having guiding significance for eliminating the risk of freeze–thaw cracking. • The cracking characteristics of concrete with holes under freeze–thaw cycles are mastered. • The plastic deformation of concrete and the seepage of water delay frost cracking of concrete. • Flexible water-repellent material prevents frost cracking of perforated concrete. [ABSTRACT FROM AUTHOR]

Climate warming sets higher requirements for sustainability in ship industry, which fuels the introduction of stricter power restrictions and new types of ship hull design. The new designs invite us to reconsider the principles in model scale testing in ice, which is the state-of-the-art method to predict vessel's ice performance prior to its construction. Ice model testing principles were originally developed for the evaluation of performance in level ice at slow speed, but currently those principles are widely applied for ice model testing in other ice conditions as well. The forces forming the vessel resistance in a brash ice channel are different compared to forces forming the vessel resistance in level ice. In consequence, the current model scale testing principles are suboptimal when predicting vessel's performance in an old, frequently operated brash ice channel, as our earlier research indicates that the prediction is conservative especially for modern merchant ship bow shapes with high stem angles. An old brash ice channel is especially interesting, as it is the determining ice condition in Finnish-Swedish Ice Class Rules ice class granting process. This paper addresses the problem by introducing a new similitude number – a Channel number – to be applied alongside the currently applied Froude and Cauchy similitudes. The Channel number aims to realistically scale the dominating forces that form the resistance of the vessel in an old brash ice channel by developing further the modelling of the resistance component induced by displacing the ice fragments. This necessitates considering the brash ice fragment interaction and inertia forces. The new scaling principle, which supplements the currently applied Froude-Cauchy scaling principle by the Channel number, is considered more accurate for brash ice conditions. It is designed to predict fairly and uniformly the ship resistance for all bow shapes avoiding potential overpowering of the modern bow types with a high stem angle. This would contribute to providing a good harmonization of ships' expected ice performance with ice classes, and, further, improve the fleet schedule predictability that the logistic chains demand from the transportation. • Current model scale testing principles are suboptimal for tests in broken ice. • This paper proposes a new scaling principle for model tests in old brash ice channels. • The new Channel similitude number considers the brash ice interparticle cohesion. [ABSTRACT FROM AUTHOR]

Thermal conductivity is one of the significant thermal parameters for estimating heat flux and thermal regime of soil in cold regions. This paper summarizes the test methods of thermal conductivity for a variety of soils, analyzes the influence of different factors on thermal conductivity and its mechanism, and evaluates the applicability of different predictive models of thermal conductivity. The transient and steady-state methods are two main test methods of thermal conductivity, and the transient method is mostly applied to measure soil thermal conductivity due to the short test time. Moreover, the test of the thermal conductivity for the remolded soil indoor is more common. Various factors affect thermal conductivity, mainly including the inherent and environmental factors. And compared with other factors, quartz content and moisture content have more significant effect on thermal conductivity. There are many theoretical, empirical and other predictive models of thermal conductivity, but few unified predictive models of thermal conductivity for various types and states of soils. However, machine learning (ML) algorithms are applicable to different types and states of soils, and which have relatively higher predictive accuracy than other common models. Future research should focus on the thermal conductivity for the coarse-grained and undisturbed soils, especially for the soils with the effect of freeze-thaw, and the predictive models considering the influence of phase change, unfrozen water content and frost heave on the thermal conductivity for the coarse-grained and undisturbed soils. This research can provide significant information for scholars to further study the variation and predictive models of thermal conductivity. [ABSTRACT FROM AUTHOR]

In cold and saline soil regions, freeze-thaw (F-T) cycles and salt erosion are two major factors determining the durability of concrete structures. This paper aims to investigate the influential mechanism and deterioration of the mechanical and microstructural properties for the concretes modified with nano-TiO 2 (NT) and nano-SiO 2 (NS) exposed to the coupled environment conditions of the F-T cycles and salt erosion. 180 F-T cycles were conducted on the concretes immersed in five kinds of environment media, namely, water (WF), air (AF), solution with a concentration of 5% Na 2 SO 4 (SSF), solution with a concentration of 5% NaCl (SCF), and a mixture solution with the concentration of 5% Na 2 SO 4 and 5% NaCl (HSF). The results indicate that the added nanoparticles and media significantly influence the overall performance of concrete samples. The SCF has the greatest influence on the degradation of concretes, following by the HSF, SSF, WF, and AF. Meanwhile, the compressive strength of concretes modified with NT is lower than that modified with NS. There is an optimal nanoparticles ratio for the nano-concrete samples to resist coupled effect of the F-T actions and salt erosion, and the optimal nanoparticles ratios for the concretes modified with NS and NT are 1% and 2%, respectively. Moreover, the filling effect on pore structure for the concretes modified with NS is better than that with NT, more hydration products and corrosion products occur on the concrete surfaces, and the crystals on the surface of concretes modified with NS are larger than that modified with NT. Furthermore, for the concretes modified with nanoparticles in the first 90 F-T actions, the gel micro-pores (<10 nm) increase, while the macro-pores (>5000 nm) decrease. However, the gel micro-pores decrease and the macro-pores increase within the 90–150 F-T cycles. This research would provide significant instructions on the exploration of the anti-erosion and frost-resistance of nano-concretes in marine and cold region engineering. • Freeze-thaw cycles of −40 °C to +25 °C were conducted on concretes. • Coupling freeze-thaw cycle and salt erosion accelerate concrete deterioration. • Deterioration caused by 5% NaCl is larger than that of 5% Na 2 SO 4. • Optimal nanoparticles ratio was determined to improve concrete durability. • Nano-SiO 2 has more excellent pore filling effect than nano-TiO 2. [ABSTRACT FROM AUTHOR]

The safety of offshore structures is often threatened by the impact load of isolated ice floes. However, the accurate estimation of the impact load can be challenging due to the unquantified near-field hydrodynamic interaction. In this paper, the hydrodynamic interactions between ice floes and offshore structures are investigated by a model experiment and the numerical calculation. The model experiment is conducted to study the whole process of a model ice drifting and impacting a cylinder under the influence of uniform flow. Meanwhile, the interaction process is also numerically simulated by using the Computational Fluid Dynamics (CFD)-Finite Element Method (FEM) coupling method. The experimental and numerical results show good agreement in terms of velocity time histories, peak impact forces and peak accelerations. The influences of current velocity, ice floe size, and ice floe shape on various interactions are discussed based on numerical results, including the velocity attenuation effect before impact, the added mass effect during collision, the kinetic energy and motion attitude of the ice floe. The main findings of present research suggest that the viscous effect in near-field and the bow wave are noteworthy factors causing the velocity attenuation of the ice floe and ignoring these influences can lead to underestimation of the velocity attenuation effect to some extent. Additionally, the (effective) added mass coefficients calculated based on the ice floe motion equation and the momentum balance equation are found to be close to each other. However, with the decreasing of the ice floe size, the difference between the added mass coefficients calculated by the two methods gradually increases. • The whole process of an ice floe drifting and impacting on a cylinder is conducted. • The shape factors that influence hydrodynamic interactions are captured. • Significant velocity attenuation has been observed for floe size larger than of cylinder. • The calculated added masses during collision based on motion equation and momentum equation are close. [ABSTRACT FROM AUTHOR]

Due to the complexity and instability of the environment in which the buried oil pipeline is located in cold regions, the corrosion of the outer wall of the pipeline often occurs, and the corrosion poses a serious threat to the safety of the pipeline. In order to ensure the safe operation of buried oil pipelines, it is particularly urgent to study the reliability of operating pipelines. In this paper, the external temperature field and soil effect were taken into account, and the finite element method was used to calculate and analyze the results. The fitted formula which can predict the failure pressure of buried corroded pipeline was obtained. After that, the reliability of buried corroded pipelines was studied by using Monte Carlo method and BP neural network. The results show that the fitted formula for predicting the failure pressure of pipelines is more accurate than traditional code. The corrosion depth has the most significant impact on the reliability of pipelines, being 1.85 times that of the corrosion length. The impact of corrosion width, burial depth, frost-heaving rate, and length of the frost-heaving section on the reliability of corroded pipelines is relatively small. The frost-heaving section within 5000 mm can play a certain positive role in the reliability of corroded pipelines. • The 3D pipe-soil-thermal-stress coupling model in cold regions was established. • A formula was derived to predict the failure pressure of pipelines in cold regions. • The reliability of corroded pipelines was studied by using MCM and BPNN. [ABSTRACT FROM AUTHOR]

This paper utilizes computed tomography (CT) real–time observation technology to investigate the damage mechanism of frozen loess under loading and unloading. The intrinsic connections between macroscopic mechanical degradation and mesoscopic damage in frozen loess were established through a comparative analysis of macroscopic mechanical parameters (such as dissipation energy and elastic strain energy) and mesoscopic structural parameters (such as porosity increment and mesoscopic structural damage increment) of frozen loess under loading and unloading. Furthermore, the relationships between damage variables at different scales under the effects of loading and unloading were explored. The experimental results demonstrate that during the elastic strain stage, the dissipated energy, porosity increment, and microscopic damage increment of frozen soil exhibit a linear increase with strain. Following loading and unloading, the porosity is unable to be fully restored to its original state due to the development of new cracks. At this stage, the deformation is not entirely elastic and includes some plastic deformation. During the plastic deformation stage, the dissipated energy tends to stabilize, while the porosity increment and microscopic damage increment continue to increase substantially. The pore structure of a specimen undergoes significant alterations, with increased displacement and rearrangement of soil particles and ongoing expansion of cracks. The damage evolution trends at both the macroscale and mesoscale remain consistent during this stage. This study offers insights into the construction of a cross–scale macroscale/mesoscale ontological damage model, serving as a valuable reference for future research. • Study investigates the damage mechanism of frozen loess under loading and unloading using CT observation technology. • The link between the degradation of macro-mechanical properties and the mesoscopic damage of frozen loess is revealed. • Explore the relationship between damage variables at different scales. [ABSTRACT FROM AUTHOR]

This paper presents results from a validation study of the EMD-WRF On Demand (OD) ICING modelling chain for production loss assessment for wind turbines in cold climates. The emphasis has been on validating the modelled seasonal instrumental icing using 29 meteorological masts and 49 seasons. The observed instrumental icing was extracted from wind data from meteorological masts using windPRO. The modelled results were compared to the observed instrumental icing and the sensitivity of the industry threshold limit of 10 g (for a 1-m-high standard cylinder) was evaluated. The study showed very good performance of the modelling chain and confirmed the industry threshold limit of 10 g (for a 1-m-high standard cylinder) to be the best match. Furthermore, the IEA Task 19 Ice Class system for translating modelling icing into a production loss was evaluated, and it was found that using meteorological icing is the desired and recommended solution. • A unique set of met mast data was used for the analysis • A unique sensitivity analysis of the use of different thresholds was shown • Results shows, that the IEA Ice class system should not be used with observed instrumental icing as inputs • The performance of the modelling tool EMD-WRF OD icing was shown [ABSTRACT FROM AUTHOR]

Ice runs and ice jams can cause significant damage to infrastructure and other human interests. Accurate modelling and prediction of these events rely on data and assumptions about river ice properties. This paper seeks to address the lack of data on ice strength distributions and associated properties in small, steep rivers and to obtain a better understanding of those. To this end, an ice data collection campaign was carried out in the Sokna river in central Norway during the 2020–2021 winter field season. The following types of data were collected for anchor ice dams and level ice sections: Borehole Jack (BHJ) in-situ ice strength, ice thickness, ice density, thin section imagery and associated depth measurements. A total of 27 ice cores and 68 thin sections were successfully collected and processed. Furthermore, a survey was carried out recording GPS coordinates of anchor ice dams in the river. Meteorological and hydrological data was also collated, and large boulder location data was obtained through the analysis of aerial photography. Ice strength distributions and trends on how ice strength varies in small, steep rivers were obtained from these data. A binomial generalized linear model for predicting ice dam locations was developed using field measurements and aerial photography data. This model describes how river width, slope and to a lesser degree large boulder density affect ice dam location. Sinuosity was shown to have no effect on ice dam location. This work highlights the significant variation in microstructure and large-scale structure of ice in small, steep rivers. • A statistical model for the prediction of anchor ice dam locations is proposed. • In-situ BHJ ice strength measurements of anchor ice dams are collected and trends considered. • Anchor ice thin section data collected and correlation between microstructure and strength considered. [ABSTRACT FROM AUTHOR]

Cold regions including the Arctic are warming fast, resulting in increased losses of snow and ice cover. A climate intervention approach, where hollow glass microspheres (HGMs) are applied on snow and ice surfaces such as Artic sea ice has been suggested for ice preservation. HGMs are commercial materials, typically in the 10–200 μm diameter size range. They are very lightweight, highly reflective materials with a high crush strength. It is suggested that through that reflectivity, their application onto snow and ice surfaces can increase the albedo, and thus stabilize snow and ice covers, for example aid the formation of multiyear sea ice. In this study we tested the stability and behaviour of different HGMs under stress conditions to gain knowledge on their potential environmental fate. Stability tests, measured as maintenance of positive buoyancy, during sediment interaction, repeated freezing and thawing and prolonged exposure in seawater showed differences in environmental stability of the tested materials with stability depending on wall thickness and surface integrity. None of the tested materials seemed to be very susceptible to biofouling under the conditions tested. However, leaching of elements, especially Si was observed for some materials, potentially indicating dissolution of the HGMs in seawater over time. Further studies are needed to determine the element dissolution from HGMs and other potential environmental implications such as impacts on organisms. Although this paper is directed towards using HGMs in a local climate intervention application the findings may be of general interest for other uses of HGM materials. • Four types of HGMs were characterized for their behaviour and fate in the (Arctic-) marine environment. • Stability, defined as maintenance of a positive buoyancy, varied between the different HGMs under the tested conditions. • Biofouling was limited, but the presence of bacteria did affect buoyancy of some HGMs. • The release of Si and Zn into seawater recommend further study of HGM dissolution and element leaching. [ABSTRACT FROM AUTHOR]

Ice accretion has been a persisting issue in cold regions and poses a threat to both onshore and offshore infrastructure, especially to sensitive equipment and personnel safety. Thermal infrared imaging (thermography) can be used as a non-destructive, non-invasive technique to determine the presence and thickness of ice over a surface. This paper presents early-stage experiment results with a FLIR® Lepton 2.5 radiometric thermal IR camera (resolution 80 × 60) to detect ice. Other technical aspects are also studied qualitatively, and corresponding results are validated against a high-speed, high-resolution FLIR® T1030SC thermal IR camera. The presented results are the first step in detecting and mitigating ice on flat surfaces. This technique may lead to the development of autonomous, remote, economical ice detection and mitigation system. • An application of active infrared thermography in the field of ice accretion has been discussed to detect ice. • A comparison of infrared images obtained from low-cost FLIR® Lepton and an expensive FLIR® T1030SC IR cameras has been presented for a laboratory experimentation. • Noise removal and morphological operations are applied to extract edges of an ice block with known dimensions and qualitative analysis is carried out for both the cameras. • A conceptual design of autonomous ice protection system based on thermal infrared imaging as ice detection technique is presented. [ABSTRACT FROM AUTHOR]

For the existing tunnels, only few of them are circular sections, the most of them are approximately elliptical sections. Correspondingly, the existing analytical solution researches basically focus on the circular tunnels. To study the distribution law of temperature field of an elliptical section tunnel in cold region, the conformal mapping method is adopted in this paper. Through the conformal mapping method function, a circular function in complex variable space is transformed into an elliptic function in Euclidean space, and then the analytical solution of variation law of temperature field of elliptic section tunnel is derived based on the analytical solution of temperature field of a circular tunnel in complex variable space. An analytical solution example for the temperature field distribution of an elliptical section tunnel in cold region is derived, the calculation results show that: (1) Sizes and variation rates of elliptic freezing surface are greatly affected by freezing time. At the outset, the elliptic freezing surface changes relatively quickly with the increase of freezing time, but the elliptic freezing surface changes relatively slowly when the freezing time is relatively long. (2) The temperature values on a certain elliptic cross section surface decrease with the increase of freezing time. (3) The ratio of the major semidiameter to minor semidiameter of elliptic freezing surfaces is getting closer to 1 with the increase of freezing time. It is also said that the elliptic freezing surface changes from ellipse to circle with the freezing time increasing. By comparing the analytical solution with the numerical solution, it is found that the analytical solution proposed in this paper has high accuracy. This study can provide important theoretical and engineering guidance for the evaluation, design, construction and maintenance of tunnel engineering in seasonally frozen soil regions and permafrost regions, and this study also has important scientific value. • An analytical solution of variation law of temperature field of elliptic section tunnel is derived. • Influences of freezing time on the rate of variation and size of elliptic freezing surfaces are analyzed. • By comparing to the numerical solution, it is found that the analytical solution proposed in this paper has high accuracy. [ABSTRACT FROM AUTHOR]

Sodium chloride (SC) is by far the most cost-effective deicing agent in winter road maintenance and therefore is used by road authorities worldwide. However, chloride ions foster high corrosivity, which significantly reduces the service lifetime of metals and reinforced concrete of transport infrastructures. Hence, a holistic evaluation with the main criteria of deicing performance and corrosion is demanded and, if possible, alternatives should be considered. This paper focuses on the deicing performance of sodium chloride and other common acetate-, carbonate-, chloride- and formate-based deicing agents. A newly developed test method is presented, enabling high volume testing at good repeatability. From its results a nonlinear model is derived to predict deicing performance up to five hours after application. Subsequently, this model is compared with both existing empirical and theoretical approaches for evaluating the deicing performance. In addition, the impact of added corrosion-inhibiting substances like sugars on deicing performance is investigated. Finally, a comparison of all tested substances in terms of corrosivity and deicing performance is presented, with corrosion being investigated in detail in another paper. • A new method for evaluation of deicing performance is presented (called CEDA). • CEDA is compared to other theoretical and empirical evaluation methods, showing the possible limit of the theoretical approach. • CEDA is a more reliable and more efficient testing method compared to the common SHRP method. • Statistical analysis shows the variation of the time-dependent deicing performance of different deicing agents. • Deicing performance is compared to mass loss due to corrosion, showing advantages of certain deicing agents and inhibitors. [ABSTRACT FROM AUTHOR]