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• The mechanism of rolling resistance of asphalt pavements is presented. • The measuring and modelling approaches of rolling resistance are summarised. • The prediction methods of fuel consumption and environmental impact are reviewed. In the context of climate change and global warming, the attention on the environmental cost of pavements is increasing. To scientifically quantify the environmental cost of pavements, accurate prediction of rolling resistance and fuel consumption is important. In this paper, a comprehensive review on rolling resistance of asphalt pavements and its environmental impact was presented. At first, the commonly used definitions of rolling resistance and texture characterisation methods of pavement surface were introduced. Then, the influence of different factors on rolling resistance was discussed. Next, the measuring and modelling approaches of rolling resistance were reviewed. At last, methods which can be used to predict fuel consumption and environmental impact were presented. It was found that an ideal approach for texture characterisation of pavement surface is to make use of the entire wavelength spectrum of road profiles and consider the enveloping curve of tire treads. Furthermore, the fact that rolling resistance can be influenced by different factors introduces difficulties in accurate measurement and modelling of rolling resistance. Moreover, testing methods and conditions have a significant effect on the empirical modelling of rolling resistance, while it is difficult and time-consuming to consider all the energy loss in the computational modelling of rolling resistance. In addition, the prediction of fuel consumption and environmental impact highly depends on the formulating methods and measuring conditions. The work presented in this paper will help to gain more insight into rolling resistance and its environmental impact, which ultimately promotes the construction of environmentally friendly pavements. [ABSTRACT FROM AUTHOR]

• The research papers related to FRGC were reviewed and classified into sub-categories depending on the fibres type. • The effects of different fibres types and their parameters on the physical, mechanical and microstructural properties of geopolymer composites have been investigated. • The research lacking in the FRGC field was highlighted. • FRGC can be a potential solution for structural applications with excellent performance. Cement industries that produce the primary component of concrete remain one of the main challenges to the world since they change the climate and possess a negative impact on sustainability. Due to climate change, the earth's temperature has increased and reached a higher level in recent years that in turn results in a distressed environment for all living beings for survival. All the consequences that scientists warned would occur as a result of global climate change in the past are now occurring: rapid sea-level rise, sea ice loss and longer, more intense heat waves. Geopolymer materials are considered as one of the solutions to reduce greenhouse gas emissions from the cement industry. Geopolymers provide the industry with great potential and sustainable alternatives to ordinary Portland cement (OPC). However, when subjected to flexure and tension stresses, the geopolymer's inherent brittleness displays drawbacks like OPC; both need fibre reinforcement to control cracks propagation, enhance toughness and deformation. As a result, the development of fibre-reinforced geopolymer composites (FRGC) has attracted increased attention, with a wide range of fibres being used. This study presents a review of the published papers on the FRGC; the research papers were reviewed and classified into sub-categories depending on the fibres type. The physical, mechanical and microstructural properties of geopolymer composites were discussed in detail. By reviewing the literature, it is evident that the FRGC can be a potential solution for structural applications with excellent performance. The improvements in geopolymer properties with the fibre addition have paved the way for further studies in this regard to exploring its performance in unused areas. [ABSTRACT FROM AUTHOR]

• This paper overviews the developments of LCA for RAC. • This paper identifies the research trend of LCA shifts with the promotion of RAC technology. • Variations of mix design and inconsistencies from LCA mechanism could be explored further. Recycled aggregate concrete (RAC) is expected to a sustainable solution to alter the virgin aggregate concrete (VAC) in structural use. While it is able to address environmental issues for both virgin aggregate (VA) consumption and waste generation, not so many studies quantify the environmental burdens through life cycle assessment (LCA). RAC is a composite material, which LCA should be analysed by considering its mixtures, and corresponding production technologies. This aggravates the complexity of LCA model since it involves great numbers of unit processes. Through reviewing 90 articles, this paper overviews the developments of LCA for RAC, and identifies the research trend shifts with the promotion of RAC technology. Although many relevant studies have become more comprehensive, there are still numerous inconsistencies and uncertainties existing in LCA processes that avoid LCA results from comparisons. From the review, it clearly points out that results are greatly affected by two aspects that are mix design and LCA mechanism. Cement production has the predominant contribution to the environmental impacts of concrete, and normally followed by transportation process. Accordingly, mix design, together with treatment technology of raw materials, influence the overall environmental performance of concrete. With respect to LCA phases, selections of FU, system boundary, allocation rule, LCI and LCIA methodology are highly subjective, causing more uncertainties that hinder the comparisons across the studies. It is therefore suggested that variations of mix design and inconsistencies from LCA mechanism could be explored further in the field of RAC to establish the holistic and multi-criteria study for comparison and decision making. [ABSTRACT FROM AUTHOR]

Abstract: Natural weather changes due to diurnal and seasonal temperature and relative humidity cycles affect micro-environment of concrete; temperature and moisture content in the concrete fluctuate correspondingly with variations in the weather. At the same time, for concrete structures, the temperature and relative humidity in both the atmosphere and the concrete show obvious differences due to thermal conduction and pore structure densification of the concrete. Therefore, the temperature and moisture content in the concrete, which are defined as the micro-environmental indexes in the concrete in this paper, are main factors directly influencing concrete carbonation, chloride diffusion and the corrosion rate of steel bars. This paper mainly discusses the climate load based on natural weather and the effects of the climate load. The climate load includes the temperature, relative humidity, wind speed, sun shine and rain in a natural climate environment. The effects of the climate load are the responses of the micro-environment in the concrete under action of the climate load. Firstly, the experiments on responses of temperature and relative humidity in concrete were carried out in an artificial constant climate environment; at the same time, the behaviors about thermal conduction and moisture diffusion of the concrete were measured and modeled. Thereafter, a method for predicting the responses in concrete under a natural climate environment condition was built. In present studies, the temperature and the relative humidity responses in concrete under a natural climate environment condition show obvious hysteresis characteristics. The research findings illustrate that the predictions of the rate of the concrete carbonation, the chloride diffusion and the corrosion of bar in concrete should be depended on the micro-environment and the predictions based on the natural climate environment are not appropriate. [Copyright &y& Elsevier]

• Resilience of cultural heritage to climate change requires multidisciplinarity. • New method for material degradation risk mapping in masonry buildings is proposed. • Structural-thermal models and field tests are used to study climate change hazard. • Interactions between climate change and structural damage are highlighted. • Application to the Consoli Palace provides priorities of intervention on the façade. Resilience of new and existing buildings to climate change is a key research issue. Climate change-related phenomena can considerably affect buildings mechanical and thermal-energy response by contributing to materials degradation and structural safety. Such an impact is even further exacerbated in historical constructions, more vulnerable to such events due to their ancient structure if compared to recent designs. The purpose of this paper is to propose an innovative, integrated, multidisciplinary methodology for assessing construction materials' degradation in historic masonry buildings and its potential future evolution, providing a risk mapping accounting for interactions between climate change effects and structural damage. Such a replicable approach consists in (i) preliminary site inspections, (ii) damage and degradation surveys, (iii) development and calibration of numerical models predicting structural-thermal response and (iv) prediction of materials degradation accounting for future climate conditions and potential worsening of structural damage. The final output of the procedure is a hierarchical mapping of regions with different degradation severities, by identifying those where a specific type of degradation or damage insists but are likely stable and those where they are expected to get worse due to changes in future climate conditions or to a negative interaction between degradation and damage. The presented approach is applied to an iconic Italian monumental building, the Consoli Palace in Gubbio, where future climate scenarios up to 2080 are simulated according to the IPCC climate change predictions. Results highlight that thermal-energy and structural aspects need to be jointly considered in the preservation of surface materials of historic buildings exposed to climate change severity. [ABSTRACT FROM AUTHOR]

• Joints govern the behaviour of a timber structures. • Weathering of the joint generally caused a degeneration of the joint's performance. • Weathered joints with steel plates decreased their capacity by 31%. Timber-framed architecture is an important heritage common of many countries. However, this is being lost due to natural decay but also climatic changes and natural hazards. To preserve it, it is important to understand the influence of such actions. Timber joints significantly affect the mechanical performances of timber-framed buildings, being the weakest element. In this paper, results are presented from cyclic pull-out test conducted on traditional timber joints subjected to wind driven rain and flood, both unreinforced and retrofitted, and a comparison is made with those obtained from sound specimens. Wetting-drying cycles mainly influence the stiffness and dissipation capacity. [ABSTRACT FROM AUTHOR]

Highlights • Review of different design and modelling methods for track drainage in railways. • Classification of drainage systems in railways. • Construction description techniques. • Highlights and recommendations to choose the best system. • Adaptation and resilience in drainage. A new design tool. Abstract The effect of water must be considered during the different phases of the life cycle of infrastructures. When it is not properly managed, it can generate problems that may lead to infrastructure closure or even destruction. This paper presents a review of the different drainage systems existent in railway infrastructures. Current design criteria have become obsolete in many cases due to effects of climate change. Therefore, the purpose of this article is to serve as a starting point for new designs. To offer measures to address this problem and increase the resilience of the structures by means of a new design tool. [ABSTRACT FROM AUTHOR]

Abstract: The paper explores the similarity between concrete and the human body in regard to the influence of temperature and moisture conditions on health and performance. Once these similarities (and in some cases differences) are understood, human senses can provide useful information about the likely effects of ambient conditions on recently cast concrete. After developing the relevant principles, the paper explores a number of examples taken from the diverse and highly variable environment of New Zealand. Examples include the effects of wind, humidity, rapid drying, and hot and cold temperatures. [Copyright &y& Elsevier]

• Both autogenous and autonomous self-healing mechanisms of concrete are reviewed. • Various factors and their correlation to the healing mechanisms are comprehensively compiled. • Various parameters and crack width are all important for healing efficiency. • The use of water to facilitate all healing mechanisms is paramount for triggering healing processes. • Further studies are identified. The increasing awareness of climate change and global warming has pushed industries to be more conscious of their environmental impact, especially in the construction industry with the main contributor being concrete. Concrete is a material that is in very high demand in the construction industry for structural applications. However, it's a material with a major concern with the challenges of microcracking. New technology has seen the development of self-healing material, using novel techniques to bring cementitious materials back to its original state. This paper reviews and evaluates the novel techniques adopted by the researchers in the field to achieve a self-healing material, with the main focus being on the factors influencing the mechanisms of autogenous healing and bacteria-based healing. Various parameters including bacteria type, pH, temperature, nutrient, urea, and Ca2+ concentration, bacteria concentration and application, pre-cracking, healing condition, cement type, and crack width are all important for healing efficiency, although the use of water to facilitate both autogenous and ureolytic bacteria healing mechanism is paramount for the triggering of healing processes. This study thoroughly presents various factors and their correlation to the healing mechanisms of autogenous healing and ureolytic bacteria healing. Further studies are identified to better understand the exact mechanism taking place and which healing process contributed to how much of the healing, and this review could serve as an informative platform for these pursues. [ABSTRACT FROM AUTHOR]

• A comprehensive review of geopolymer mortar and concrete with mineral admixtures. • A total of 126 research papers spanning a period of 22 years are reviewed. • Mineral admixtures effects on fresh, mechanical and durability properties. • Use of OPC, GGBFS, Nano-silica, Metakaolin, and Alccofine in Geopolymer products. • Microstructure analysis of geopolymer mortars and concrete is reviewed. • Research gap has been identified and elaborated. The climatic changes associated with global warming due to greenhouse gases emission from cement production attracted researchers towards geopolymer based cementitious materials. Nowadays researchers are in a continuous process to improve the mechanical properties of geopolymer mortar and concrete at ambient temperature curing condition so as to broaden its scope of utilization in building construction. The review paper summarizes the effect of various mineral additives on mechanical, durability and microstructure characteristics of geopolymer mortar and concrete. Research findings revealed that geopolymer products blended with these materials showed a significant improvement in mechanical and durability properties at normal temperature conditions. The results advocate that geopolymer mixtures with desired properties can be designed for ambient temperature curing condition with minerals additives which may further promote them as an environmentally friendly construction material. [ABSTRACT FROM AUTHOR]

• CatBoost regression model for prediction of surface chloride level. • The regression model has MAE and RMSE scores of 0.11 and 0.16 respectively. • Increase in chloride ingress with the increase in temperature and humidity. • Exposure zone has a significant effect on chloride ingress. • Temperature and humidity of RCP 2.6 and RCP 8.5 considered for analysis. This paper presents the effect of climate change on the long-term reliability of concrete structures due to chloride ingress. The impact has been demonstrated for three regions across the globe for the best and worst-case climate change scenarios. The methodology adopted here can be divided into three main steps. The first one is the development of a machine learning regression model using CatBoost for estimation of surface chloride levels, which is a function of temperature, concrete material properties, exposure conditions, and chloride levels in the seawater. The CatBoost model fitted over the experimental data has a mean absolute error (MAE) and root mean square error (RMSE) value of 0.11 and 0.16, respectively, and a high R2 value of 0.82. The second step is solving the coupled non-linear partial differential equation for temperature, humidity, and chloride ingress in concrete with time. A parametric study considering the effect of external parameters (temperature, humidity, exposure condition, and chloride levels in water) reveals the complexity and the dependencies of the chloride ingress process on external parameters. The final step involves the reliability analysis to estimate the time for chlorides to reach threshold levels at the rebar level using the numerical model. The input for the numerical model is temperature and humidity condition for different representative concentration pathways (RCP) scenarios, the material properties of concrete, and the exposure conditions. The reliability analysis shows that, for the concrete structure located in Dubai, UAE, and Cascais, Portugal, the mean time to corrosion initiation decreases due to climate change and it increases for the structure located in Tasmania, Australia. Further, the structures that are built in the future may have lower service life compared to the structures that were built in the past. Based on the study it concluded that it is necessary to consider the impact of climate change on service life to design resilient structures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Incorporation of up to a certain amount of combined fibers can beneficially enhance load bearing capacity and reduce the proportion of broken aggregate. • Fibers can increase the total fracture energy (particularly post-peak G f) and consequently reduce the fragility index by obstructing crack propagation. • Integration of fibers can improve mixtures' moisture susceptibility and reduce the negative effects of moisture damage. • The destructive impact of an increase in temperature is more dominant compared to the number of freeze and thaw cycles. • The combination of the response surface method and image analysis techniques exhibited a great capability to detect and quantify adhesion and cohesion failures. This paper evaluates the performance of fiber-reinforced mixtures subjected to moisture damage. Response Surface Method was used to design an experimental matrix based on the central composite design. The amounts of fibers, number of freeze and thaw cycles, and testing temperatures were considered as factors, while maximum load, stiffness, indirect tensile strength, CT index , fragility index, broken aggregate, and adhesion failure were regarded as the responses. Indirect tensile strength test and 3D image analysis were conducted to characterize mixtures' fracture properties and moisture susceptibility, respectively. The results show that temperature exhibits the highest influence on mixtures' mechanical properties as well as adhesion and cohesion failures. An increase in the number of freeze and thaw cycles deteriorated the mixtures' performance. Although higher beneficial impacts of glass fiber were reported earlier, this study proved that the performance of the mixtures prepared with combined fibers is comparable with the previous study. This finding brings forth the advantage in cost reduction of reinforced mixtures production due to the replacement of part of the glass fiber with polypropylene fiber. In addition, it was found that a combination of utilized fibers up to approximately 0.2% by weight of aggregates exhibited beneficial impacts on load bearing capacity, indirect tensile strength, and proportion of broken aggregate while exceeding this amount was not favorable which was correlated to the jeopardizing of cohesion level between mixtures constituents. Moreover, it was observed that fibers slightly reduced the fragility index by obstructing crack propagation. It was finally concluded that a higher amount of fibers enhanced mixtures' moisture resistance and diminish the negative effects of freeze and thaw cycles. [ABSTRACT FROM AUTHOR]

Climatic actions such as rain, sun or ice are one of the major contributors in asphalt pavement degradation. The effect of these climatic agents can be a long-term process of asphalt mixture deterioration when long rainy or sunny periods are expected as well as a series of freeze–thaw cycles due to wide range of temperature. However, laboratory studies are mainly focused on short-term effect from climatic actions. Thus, the present paper aims to analyze the evolution of the strength and bearing capacity of asphalt mixtures exposed to long-term moisture, several freeze–thaw cycles and diverse days of thermal aging. In addition, the recovery of the material mechanical properties was evaluated when a rest period was applied after climate processes. This study was developed for two different asphalt mixtures (dense and open), finding that air void content has significant influence on the trend of the long-term evolution of mixture properties under moisture action, which is a reversible process unlike the other two climate agents studied. On the other hand, freeze–thaw cycles whose effect is higher on dense mixtures was found to be a short-term process regardless the air void content while thermal aging presented the lowest variations in the properties measured for both types of asphalt mixtures. [ABSTRACT FROM AUTHOR]

Abstract: There is nearly unanimous consensus amongst scientists that increasing greenhouse gas emissions, including CO2 generated by human activity, are affecting the Earth’s climate. Increasing atmospheric CO2 emissions will likely increase the rates of carbonation in reinforced concrete structures. In this paper, the serviceable life, from construction through to cracking due to carbonation induced corrosion of concrete infrastructure is considered in various cities throughout the world. It was concluded that global climate change will affect the progression and will result in much higher ultimate carbonation depths in the long term. [Copyright &y& Elsevier]

Abstract: Temperature and moisture content are the main factors that influence concrete carbonization, chloride diffusion, and corrosion rate of reinforced bars placed in concrete. Climate variations can induce the variation of the micro-environment of concrete. Therefore, temperature and relative humidity in the natural climate environment serve as the climate load, and the variations in the micro-environment corresponding to the climate variations are the effect of the climate load. Based on these, the present paper attempts to build climate temperature and relative humidity action spectrums as a climate load model. The climate action spectrums of temperature and relative humidity are built based on meteorological data of the temperature and the relative humidity variations. The effects of sunshine and rain are included in the construction of the action spectrum. Series of tests are conducted under artificially controlled climate environment (ACCE) and natural climate environment (NCE) conditions to support the construction of the spectrum. [Copyright &y& Elsevier]

Abstract: In recent years, numerous attempts have been made to reduce the global environmental and associated socio-economic impacts of construction activities to achieve sustainable development goals. A sustainable system or activity refers to an eco-friendly, cost effective and socio-politically viable solution. This paper utilizes triple-bottom-line (TBL) sustainability criteria for the selection of a sustainable flooring system in Tehran (Iran). Three types of block joisted flooring systems – concrete, clay, and expanded polystyrene (EPS) blocks – have been investigated using life cycle analysis (LCA). Proposed approach provides a comprehensive evaluation system based on TBL criteria that are further divided into thirteen sub-criteria. It includes: (1) Environmental concerns (resource depletion, waste and emissions, waste management, climate change, environmental risk, embodied energy and energy loss); (2) Economic concerns (material cost, construction cost, and occupation and maintenance cost); and (3) Socio-political issues (social acceptance, vulnerability of area, and building weight). Analytical hierarchy process (AHP) is used as a multi-criteria decision making technique that helps to aggregate the impacts of proposed (sub)criteria into a sustainability index (SI) through a five-level hierarchical structure. Integration of AHP and LCA provides a framework for robust decision making that is consistent with sustainable construction practices. A detailed analysis shows that the EPS block is the most sustainable solution for block joisted flooring system in Tehran. [ABSTRACT FROM AUTHOR]

• Critical review for methods, and technologies for recycled aggregate. • Various methods are reviewed, including self-healing, bacterial, etc. • Existing studies to improve the properties of the recycled aggregate, are limited. • Density improvement techniques of chemicals and reactions are limited. Recycled concrete aggregate is a demolition concrete waste, which could be an environmental-friendly building material and can be a serious contender for saving natural aggregate and reducing environmental pollution. Nevertheless, the use of the same is limited, as it has inferior qualities compared to virgin aggregate, such as low density, high porosity, high water absorption rate, micro cracks in residual mortar and at the interfacial transition zones. Thereby, the need of improving the properties of recycled aggregate is vital to enable a wider adoption of the same. This paper provides an insight into identifying knowledge gaps and as a critical review for the methods, technologies, its advantages and disadvantages for improving the microstructural and mechanical properties of recycled aggregate, such as self-healing methods of re-hydration, bacterial and micro-encapsulation, sequential mixing approaches, removal of adhered mortar, permeation of solutions, coating with solutions and CO 2 carbonation approaches. The existing studies to improve the properties of the recycled aggregate, are limited and the density improvement techniques by permeation of chemicals and/or reactions have only been superficially studied. [ABSTRACT FROM AUTHOR]

• "Degree of carbonation" DoC, is a different concept than the depth of carbonation. • The DoC, is not higher when higher is the carbonation depth. They are independent. • DoC depends on the concrete humidity being highest in natural non-sheltered conditions. • After 2 years the DoC is independent of the age of the concrete. Cement manufacture is contributing to CO 2 emissions as calculated by the Intergovernmental Panel for Climatic Change of 520 kg of CO 2 per tonne of clinker. However, hydrated cement phases in concrete, absorb CO 2 through the carbonation of cement paste. Recently several studies have been published on the CO 2 uptake assuming a theoretical degree of carbonation, DoC, and multiplying it by the amount of concrete produced in the country, as made in the Annex BB of standard EN 16757 for the European Environmental Declarations. Present paper shows a study made in Spain on the CO 2 uptake during 4 years with two types of concretes, fifteen cements and three environments. The statistical analysis of the results indicated an average value of the degree of carbonation (DoC) for all cement types, except those containing high proportions of GGBS, of around 62.5% with a lower limit of 23% for the lower 5% fractile in the representation of the statistical distribution of values as a normal distribution. [ABSTRACT FROM AUTHOR]