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The construction industry, a significant contributor to global carbon emissions, is pivotal in implementing carbon reduction strategies. This study delves into the carbon emissions associated with the construction stage of prefabricated buildings (CSPB), a burgeoning field of research. Utilizing the CiteSpace knowledge graph visualization software, we comprehensively analyzed literature from the Web of Science (WoS) database. Our study encompasses several vital dimensions: academic paper publication volume, keyword co-occurrence network, keyword co-occurrence network clustering, and citation burst visualization and analysis. The findings indicate that the topic of carbon emissions in prefabricated building construction is gaining increasing attention globally. Over the past decade, related literature has surged by an average annual growth rate of 41.42 %. Key research themes have emerged around the quantification of carbon emissions, construction methodologies, influencing factors, mitigation strategies, the use of prefabricated components, and predictive studies on emissions. These insights underscore the evolving focus and critical importance of this field in global sustainability efforts. [ABSTRACT FROM AUTHOR]

For improving the dynamic management performance of construction cost, the dynamic control model of cost of construction based on fuzzy neural network is studied. Consider the effect of resource allocation, construction progress and construction quality on the cost of project in construction stage, and build the cost control index for the project in stage of construction. The fuzzy logic model is used in selecting the main cost related indicators from project cost control index system at the construction stage as input neurons of the BP NN, and the BP neural network is employed to output the results of prediction of cost at the construction stage. The project cost prediction results are set as the data basis for the dynamic control of the project cost, determine the most optimistic cost, the most probable cost and the most pessimistic cost of project cost in stage of construction through key chain method, and set buffers to realize dynamic control of project cost in stages of construction. The evaluation results prove that the developed method will be able to accurately predict the project cost in stages of construction, and the cost saved in the construction phase of the project is more than 300000 yuan.

The semi‐underground double‐storey squat silo (SUDSSS) is a new type of silo with the advantages of preserving grain quality. In this paper, a numerical model of SUDSSS was constructed using solid elements. The proposed numerical model was validated by test results of an experimental underground silo, and the results demonstrated that: (1) Before and after backfilling, the radial and circumferential stress of the underground storey reached their maximum at 2/3 from the bottom and 2/3 from the ground surface, respectively; (2) As the height of grain storage increases, the silo wall stress in the overground storey increases. From the top of the underground storey up to 1/4 height of the overground storey, the stress of silo wall increases. (3) For the underground storey, the maximum stress occurs at 1/3 of the way from the apex of bottom cone. Practical applications: The semi‐underground double‐storey squat silo is a new grain storage device proposed by this paper, which consists of two layers. The lower layer is located in the ground and can utilize the shallow ground temperature to realize the green and low‐temperature storage of grain, the upper layer is conducive to the turnover of grain, which can ensure the quality of grain storage. The new silo has the advantages of saving land, energy saving and carbon reduction. Based on the silo, this paper investigates the stress–strain properties of the silo before and after soil backfilling during the construction stage, and obtains the change pattern of the static mechanical properties of the silo. This paper analyses the mechanical properties of semi‐underground double‐storey squat silo under different storage conditions at the grain storage stage, and studies the change patterns of the mechanical properties of the silo body under different storage heights. [ABSTRACT FROM AUTHOR]

Steel–concrete composite girder rigid frame bridges with V-shaped piers are a new type of bridge structure. Based on the traditional composite continuous beam bridge, part or all of the vertical piers are changed into V-shaped piers. This special structure makes them have the mechanical characteristics of both composite continuous beams and V-shaped piers. In this paper, the finite element model of the first steel–concrete composite continuous beam V-pier rigid frame bridge in China is established by simulation software, the construction process of the bridge is simulated, and the stress and deflection of the bridge in each construction stage are studied. At the same time, the stress of the completed bridge model considering the construction stage is compared with that of the completed bridge model without considering the construction stage. It is found that the stress difference between the two concrete slabs is as high as 2.7 MPa. The results show that the stress state of the bridge is greatly affected by the construction process. This study can provide guidance for the design and construction of such bridges, which is of great significance. [ABSTRACT FROM AUTHOR]

China's overseas economic and trade cooperation zones (COETCZ) have become an important platform for Chinese enterprises to "go global". How to achieve high-quality develop‐ ment of COETCZ is the realistic demand of the Belt and Road Initiative. Therefore, based on the field survey of COETCZ in Southeast Asia, this paper summarizes the construction modes of COETCZ in different development stages and the development strategies adopted, in order to provide experience reference for COETCZ to achieve high-quality development. For the con‐ struction of COETCZ in southeast Asia, the construction modes and development strategies ad‐ opted in different development stages are selected as follows :(1) In the initial stage of invest‐ ment, the construction tasks completed include confirming location selection, selecting invest‐ ment and financing modes and formulating park planning. According to the differences of the development experience and the national conditions of the host country, the location selection strategy of the park developers can be divided into two models. According to the difference of capital capacity and land ownership of host country, there are three investment and financing modes. According to the differences in the construction experience of the park developers, there are two development strategies. (2) During the development and construction period, the com‐ pleted construction tasks include the development and construction of infrastructure and invest‐ ment attraction. According to the differences of park developers' development and construction experience and capital capacity, the development and construction of infrastructure can be divid‐ ed into three strategies. According to the difference of the attraction ability of developers in the park, the attraction work has formed three modes. (3) During the operation and management pe‐ riod, the construction tasks completed include improving operation and management and inte‐ grating into the local environment. According to the operation management ability of park devel‐ opers and the degree of policy support of host country, the strategy selection for improving oper‐ ation management can be divided into three types. In terms of the strategy selection of integra‐ tion into the local environment, specific development strategies of different park developers vary greatly, but can be generally divided into three types. [ABSTRACT FROM AUTHOR]

In response to land use challenges, major urban centers have started implementing over-track building constructions above metro lines as a means of accommodating residents and workers. However, the continuous operation of trains can generate excessive vibrations that may negatively impact the overall living conditions for occupants residing in these structures. In this paper, vibration measurements were conducted on the soil and within a three-story frame structure building. Additionally, a three-dimensional finite element model of the track–soil–building was established. The wheel–rail contact force was incorporated as a dynamic load that varies with time to accurately simulate the vibration response induced by trains. According to the construction process of the over-track building, four construction stages were set up using the finite element model to study the impact of the construction stages on the vibration propagation from the soil to building structure. The results indicate that the presence of existing structures exerts a mitigating influence on soil vibrations. Pile foundation construction can effectively mitigate soil vibration to a significant extent. The findings provide references for the future development and design of over-track buildings. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Steel–concrete composite girder rigid frame bridges with V-shaped piers are a new type of bridge structure. Based on the traditional composite continuous beam bridge, part or all of the vertical piers are changed into V-shaped piers. This special structure makes them have the mechanical characteristics of both composite continuous beams and V-shaped piers. In this paper, the finite element model of the first steel–concrete composite continuous beam V-pier rigid frame bridge in China is established by simulation software, the construction process of the bridge is simulated, and the stress and deflection of the bridge in each construction stage are studied. At the same time, the stress of the completed bridge model considering the construction stage is compared with that of the completed bridge model without considering the construction stage. It is found that the stress difference between the two concrete slabs is as high as 2.7 MPa. The results show that the stress state of the bridge is greatly affected by the construction process. This study can provide guidance for the design and construction of such bridges, which is of great significance.

In response to land use challenges, major urban centers have started implementing over-track building constructions above metro lines as a means of accommodating residents and workers. However, the continuous operation of trains can generate excessive vibrations that may negatively impact the overall living conditions for occupants residing in these structures. In this paper, vibration measurements were conducted on the soil and within a three-story frame structure building. Additionally, a three-dimensional finite element model of the track–soil–building was established. The wheel–rail contact force was incorporated as a dynamic load that varies with time to accurately simulate the vibration response induced by trains. According to the construction process of the over-track building, four construction stages were set up using the finite element model to study the impact of the construction stages on the vibration propagation from the soil to building structure. The results indicate that the presence of existing structures exerts a mitigating influence on soil vibrations. Pile foundation construction can effectively mitigate soil vibration to a significant extent. The findings provide references for the future development and design of over-track buildings.

The influence of the construction period of the bridge project across the reservoir on the adjacent power station includes not only the direct impact on the hydropower hub but also the impacts on the reservoir area, flood discharge, power station head, water diversion and sediment prevention, power generation operation, and other factors. In this paper, from the aspects of the power station operation, an evaluation index for the influence of the construction period of a bridge across a reservoir on the adjacent power station is developed, and an evaluation system is constructed. Based on the constructed evaluation system, the influence of the bridge construction period on the adjacent power stations is analyzed. This evaluation system provides a reference for the impact assessment of cross-reservoir bridge engineering on adjacent hydropower stations. [ABSTRACT FROM AUTHOR]

Based on the engineering background of a long-span steel-concrete composite girder cable-stayed bridge with the main span of 442 m, a three-dimensional spatial finite element model of the bridge was established by way of Midas Civil in this paper to study the feasibility of stress-free state method in the simulated analysis of the construction control of a cable-stayed bridge. First, the relationship between the construction state and the completed state of the bridge is established based on the stress-free state method; and then, using the corresponding stress-free length of the cables in the completed bridge state as the formal assembly in the construction stage to analyze and eliminate the influence of nonlinear and other factors. After several iterative analyses, the completed cable force and the target cable force can be closed, and the bending moment of the main girder tends to the target bending moment. The monitored data after the completion of the construction show that the stress-free state method can well simulate the construction process of the cable -stayed bridge and the reliability and convenience of simulation analysis of construction control of cable-stayed bridges using the stress-free state method are verified, which can provide a reference for simulation analysis of similar cable-stayed bridges. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To rapidly evaluate the seismic resilience of the bridges under construction, the construction stage seismic resilience evaluation method was proposed. Based on a case bridge of continuous girder with the cast-in-place cantilever construction method, the seismic resilience of bridges at different construction stages was researched and compared. The bridge model was established by utilizing the construction stage module in the Midas Civil finite element modelling software. The functional losses of the bridges at different construction stages were computed. The three dimensional functional surfaces of Function-Time-PGA (Peak Ground Acceleration) were drawn. The resilience indexes at different construction stages with different seismic PGAs were compared, the resilience indexes with and without consideration of the delay recovery period were compared and analysed. The research results show: 1) in the control period, the functional loss is directly proportional to the PGA, but the function and resilience indexes are inversely proportional to the PGA; 2) the seismic resilience indexes of bridges at different construction stages are vastly different; 3) the resilience indexes with and without consideration of the delay recovery period are different; for the case bridge with the delay recovery period to recovery period ratio of 20%, the difference of the resilience indexes with and without consideration of the delay recovery period can reach 17% when the seismic PGA is 1.0 g. This paper provides a new method to evaluate the seismic resilience of construction stages, and it can be used to provide suggestions for the seismic damage evaluation and post-seismic recovery scheme.

This study examines the differential impact of HSR station and airport on local debt risk during the construction and operation stage. Based on the data of China's prefecture-level cities from 2010 to 2019, Feasible Generalized Least Square (FGLS) model results show that HSR station under construction reduces local debt risk by attracting extra-municipal capital inflows. However, the more HSR stations and airports are opened, the more local governments invest in other infrastructure, leading to increased local debt risk. By dynamic test, it is found that the longer the opening time, the greater the difference between the positive impact of HSR stations and airports on debt risk. Further synergies suggest that both local governments and investors have high expectations for urban development driven by HSR stations rather than airports, and the presence of HSR station amplifies the positive external effects of the airport construction. These findings not only deepen the understanding of the risk impact of HSR station and airport, but also provide enlightenment for countries to develop HSR station and airport through debt. • We test diverse impacts of HSR station and airport on local debt risk. • HSR station reduces the local debt risk during construction stage. • The opening of HSR and airport increases the local debt risk. • Government and investors have higher expectations for HSR-led urban development. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the shear-lag effect in the main girder of a composite twin-box girder cable-stayed bridge during construction, a full-bridge model and a local spatial model were established using the finite element software MIDAS/Civil and ABAQUS, respectively, for the main span of the Chibi Yangtze River Bridge in Hubei Province, China, as an engineering example. On this basis, the shear-lag effect in the composite twin-box girder under multiple typical construction conditions was analysed through numerical simulation, and the accuracy of the model was verified by field measurements at the construction site. Results demonstrate that as the balanced cantilever construction progresses, the stress in the deck slabs near the junction of the anchor plate and the outer web of the side box girder and at the location of small longitudinal beams changes substantially. However, the stress at other girder sections is gradually uniformly distributed, the shear-lag coefficient tends to be stable, and a phenomenon of positive and negative shear-lag effect conversion occurs in the deck slab sections of the main girder. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The construction period of large structures such as hospitals can be prolonged due to complex construction processes. The behavior of frictional pendulum systems (FPSs) is strongly influenced by the seismic weight of the superstructure and the corresponding coefficient of friction. Therefore, the effects of the isolator behavior, which varies throughout the construction stages (CSs), on structural responses should be evaluated. Existing literature lacks adequate investigation into the behavior of isolated structures subjected to earthquakes during CSs. To address this gap, this paper investigates the structural performance of a base-isolated hospital building equipped with FPSs that experienced residual displacements during the February 6, 2023, Kahramanmaraş, Türkiye earthquakes (Mw 7.7 Pazarcık and Mw 7.6 Elbistan). At the time of the earthquakes, the building was still under construction (65–70 % complete). In addition to the hospital building under consideration, there were three more hospital buildings equipped with FPSs under construction during the 2023 Kahramanmaraş-Türkiye earthquakes in Türkiye. The seismic behavior and residual displacements of the structure during this CS were evaluated and numeric results were validated with real data measured in the field. Moreover, fragility analyses were performed for different CSs of the hospital building to reveal the probabilities of damage for base-isolated buildings exposed to earthquakes at various CSs. For fragility assessment, damage states (slight, moderate, extensive, collapse) were defined and four damage measures were chosen. Thus, the extent to which construction stages affected which types of damage was determined. A total of 1296 nonlinear time-history analysis were conducted to obtain fragility curves for all CSs and damage measures considering lower bound, nominal, and upper bound values of isolators. Selected isolated hospital building showed vulnerability in maximum top floor acceleration (MTFA) and maximum isolator displacement (MID) damage measures, but resilience in maximum roof drift ratio (MRDR) and maximum inter-story drift ratio (MIDR) damage measures. For the design basis earthquake (DBE) level, the probability of reaching the extensive damage state was 5.25 % for the MID, 11.39 % for MTFA, and 0 % for MIDR and MRDR. Similarly, for the maximum considered earthquake (MCE) level, these values were determined as 34.09 % for MID, 43.42 % for MTFA, and 0 % for MIDR and MRDR. The analysis revealed that while the probability of damage to the base isolation system was not related to CSs, residual displacements increased as construction progressed. Collapse thresholds for MIDR and MRDR demand exceptionally severe seismic events. As construction progresses, probabilities of exceeding damage states increase for MIDR and MRDR, indicating heightened vulnerability. • Structural performance of a base-isolated hospital building is investigated. • The hospital building experienced residual displacements during the February 6, 2023, Kahramanmaraş, Türkiye earthquakes. • The building is still under construction at the time of the earthquakes. • Fragility analyses are performed for different CSs of this hospital building. [ABSTRACT FROM AUTHOR]

In order to explore the bearing mechanism of concrete sandwich arch roof under different supporting conditions in each typical construction stage, this paper analyzes the stress, deformation and support reaction of sandwich arch roof under five working conditions in three typical construction stages, such as storage, lifting and installation, with the help of finite element method. The results show that the small-span concrete sandwich arch roof has large overall stiffness and high bearing capacity, and appropriate support measures can be taken during component assembly construction. The arch roof structure has high stress level and full development of deformation in the lifting construction stage, should focus on the cracking of arch crown concrete and the deformation of arch foot. Under the condition of two hinged arch support, the internal force level of sandwich arch roof is low, and the difference of support reaction value of each arch foot is small. [ABSTRACT FROM AUTHOR]

The repair of historical masonry columns damaged by earthquakes is a complex engineering procedure. In most cases, these elements support important vertical loads, and, for this reason, the repairing interventions (such as block replacement) could generate critical modifications of the stress pattern and eventually lead to local failures of the masonry material. In order to prevent critical situations, the repair work should account a complete unloading-reloading process of the column. However, at this time, no specific indications are provided by technical codes and guidelines. In the present paper, the unloading-reloading process developed for the stone masonry columns of the Basilica di Collemaggio in L'Aquila (Italy) is presented. Particularly, two specific unloading systems were designed and verified with advanced finite element analyses. A three-dimensional finite element model of the colonnade and supported nave wall was implemented to check if the unloading-reloading process would significantly change the state of stress in the masonry, causing local failures. The geometry of the structure was reconstructed from a complete laser scanner survey of the church, by considering all the intrinsic irregularities of heritage constructions. Finally, a comparison between the numerical results and the corresponding values measured during the worksite intervention was carried out. [ABSTRACT FROM AUTHOR]

Bridge Hohenpolding – Influencing concrete stresses by specifying construction stages Due to the local conditions and the given design restrictions there were special demands for the design of the replacement of the bridge K‐ED 31. The limitation of the cross‐section height required an exceptional slender superstructure, for which decompression couldn't be ensured solely through a high degree of post‐tensioning. Therefore temporary supports for the construction stage were chosen and external forces were applied to take influence on the internal forces and stresses, which helped to prove that decompression was fulfilled. This article describes the design and the construction of the post‐tensioned concrete frame bridge. [ABSTRACT FROM AUTHOR]

In this paper, a new deck plate system, in which the top chords are infilled with high-performance cement-based material such as high-strength mortar and UHPC (ultra-high performance concrete), was proposed. The bending capacity of the proposed deck plate system at the construction stage was investigated by performing a four-point bending test on seven specimens with a net span of 4.6 m. Test parameters included the type of top chords, type and amount of infilled material, and existence of inner shear connectors. The load versus displacement curves were plotted for all the specimens, and their failure modes were identified. In addition, a theoretical strength estimation process was developed for the proposed deck plate system. The strength values calculated by the estimation process were compared with the test results and analyzed. This comparison showed that the proposed system retained the peak strength and initial stiffness at a much higher level than the conventional system, and the theoretical strength estimation process can predict the failure modes and peak strength of the proposed system accurately. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to clarify the stability of the long-span half-through steel box tied arch bridge during the construction phase, the Xishuangbanna Lancang River Liming Bridge was taken as the research object, and a full-bridge space finite element model was established to analyze the stability of the bridge during the whole construction phase, and the initial defects were considered. The influence of geometric nonlinearity, material nonlinearity, wind bracing, temporary wind bracing, non-directional force of suspender and wind-resistant cable on the stability of the structure during construction. The results show that the stability coefficient of the structure during the whole construction process meets the requirements of the corresponding specifications. Considering the geometric nonlinear analysis of initial defects, the stability coefficient of the structure is reduced by 7% to 8%; when the double nonlinearity of geometry and material is considered, the stability coefficient of the structure is reduced 49. 67% ~52. 05%, the material nonlinearity has a significant influence on the structural stability. Increasing the number of permanent wind braces can effectively improve the stability of the most unfavorable construction stage of cable hoisting and the construction stage after the arch ribs are closed. The placement of temporary wind bracing can significantly improve the stability of the most unfavorable construction stage of structural cable hoisting, and the non-directional force effect is centered. The stability of the through-type steel box tied arch bridge has a greater impact, and the installation of wind-resistant cables significantly improves the stability of the construction stage after the arch ribs are closed. It can be seen that there are many factors affecting the stability of the construction stage, and this study can provide a reference for the construction and design of the same type of bridge. [ABSTRACT FROM AUTHOR]

Long tunnels with significant overburden, changeable geological conditions, a steep gradient, water infiltration, and heavy traffic flow are susceptible to environmental concerns during both construction and operation. The availability of fresh air and visibility is the most important necessity in excavation for tunnel workers inside the tunnel during the construction phase, as well as those crossing the tunnel during operation. Lowari Tunnel's tunnel air pollutants were researched. Carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), hydrogen sulfide (H2S), sulfur dioxide (SO2), nitrogen oxide (NO), ammonia (NH3), nitrogen dioxide (NO2), PM1, PM2.5, PM10, air velocity, dust morphological and particle size distribution analysis are among the parameters under consideration. The findings provide evidence for the development of tunnel air quality. [ABSTRACT FROM AUTHOR]

Colossal growth of construction waste (CW) generation worldwide, and its consequential environmental and economic impact, has ensured that construction waste minimization (CWM) practice is critical. Notably, the largest proportion of waste generation that can be actively reduced within the sector lies within the construction/on-site activities stage. As such, a number of waste minimization approaches have been utilized during construction, targeted to reduce/eliminate waste with the aim to support a more sustainable construction agenda. This article provides a narrative review of related literature published in leading journals in Scopus, ScienceDirect, and Web of Science databases, to understand the fundamentals of CW and to investigate CWM implementation levels and barriers during the construction stage. This will aid in identifying research gaps for future studies and highlight key findings that will help researchers and construction industry practitioners to understand the principles of, and the need for, CWM, as well as the challenges facing its effective implementation in construction projects. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction--The construction of box girder bridges has increased in recent years in Colombia. Some previous studies have shown the significant effects in the results due to omission of the construction process, the rheological properties of the materials, and the environmental conditions can generate significant effects on the results. Due to the variety in the different territories of Colombia, it is interesting to determine the effect of these conditions on the structural response of the bridge. Objective--The main goal of the study is to quantify the variations in the structural response of the main elements of a post-tensioned box girder bridge, during construction and in service, due to changes of the relative humidity of the environment. Method--A computational model of a representative Colombia bridge studied was developed in the software Midas Civil. The model includes the time-dependent effects of the materials. Three different (extreme high, medium, and extreme low) values of relative humidity were used in the analysis. Results--The variation in the longitudinal bending moment, shear and axial forces, and the deflection of the girder, and those of the columns bending moment were calculated by varying the relative humidity of the environment. Conclusions--Negligible variations in the structural response of the bridge elements during construction after modifying the relative humidity. On the other hand, some elements (especially the girder) responses showed sensibility and considerable changes due to modification of the environment parameter. [ABSTRACT FROM AUTHOR]

Slope instabilities present significant geotechnical problems involving a variety of geomaterials in different geological and climatic environments. These phenomena, which can be natural or man-made, are difficult to predict because their initiation depends on many factors. Man-made slopes are expected in a large number of civil and mining engineering works. In civil works, slopes are common in construction of highways and railways, dams for hydropower and water supply, and urban and industrial developments. In mining engineering, they are mainly associated with open-pit mines. The work presents an overview of rock slope stability, including the impact of weathering and erosion. In Oman, the case of a large slope failure that occurred during the Musandam Independent Power construction Plant (MIPP) is used to illustrate learning lessons. A comprehensive study of slope failure was performed by developing finite element numerical models both prior and post-implementation of stabilization measures that included rock bolts, shotcrete and other measures. A safety analysis was performed with a probabilistic approach following different methodologies. Also, a sensitive study was presented considering the bedding plane orientation and considering extreme conditions like seismic loading. [ABSTRACT FROM AUTHOR]

Construction waste (CW) accounts for approximately 36 percent of the total solid waste received at landfill sites around the world and, therefore, presents a significant challenge to the sustainability of the construction industry, the country's economy at large, and environmental sustainability worldwide. For Jordan, this issue is pertinent since the construction industry is still suffering from insufficient sustainability practices characterized by poor production, sub-standard performance, and a wasteful culture. Increasing attention has been placed on addressing the role of human factors in construction waste minimization (CWM), as the majority of the causes underlying CW are directly or indirectly affected by the behavior of those working in the construction industry. However, understanding CWM behavior is most challenging and complex, as adopting positive CWM behavior depends on many factors that contribute to its success or failure. This paper describes the development of a behavioral framework (BF) that aims to address this research gap. The Delphi technique, incorporating a series of semi-structured interviews, was chosen as the primary research investigative method, for the discovery and building of the BF. Twelve respondents (the experts' panel), with extensive knowledge of and experience in the Jordanian construction industry, participated in two rounds of the Delphi study. They were able to offer a well-informed look at the current and potential status of the adoption of CWM behavior among Jordanian contractors. The resulting BF advances a more holistic understanding of the factors influencing the behavior of contractors toward CWM, which will support the adoption of waste minimization in Jordanian construction projects. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Construction of bridges by the cantilever method needs to consider the accidental release of the formwork traveller (ARFT) in the design phase. Often this phase is a critical situation that current regulations treat as a static analysis amplified by a dynamic factor due to the difficulty in setting up a model able to simulate the complex interaction between the formwork and the structure in the time domain during the accidental release. To overcome the simplistic approach of the regulations and to avoid the complexity of detailed ARFT modelling, in this research the release of the formwork is modelled as a simple force-time function applied to the bridge. This function has an equivalent effect on the structure as the accidental release, and it has been tuned using experimental tests on a 1:100 scale aeroelastic model of the cable-stayed Bioceanic Bridge. To test the applicability of the proposed time-function the Chilina continuous beam Bridge was also analysed. The article shows that the simplified procedure in the regulations can sometimes underestimate and overestimate dynamic amplification and, thus, a methodology is proposed to carry out the specific dynamic calculation that the regulations suggest for those cases where it is necessary. • Experimental tests on the scale model of the cable-stayed bridge. • Comparison with finite element model results. • Evaluation of the dynamic amplification factor in regulations. • Proposal of force functions for the numerical dynamic study. • Comparison of results between kinds of formwork travellers. [ABSTRACT FROM AUTHOR]

Long tunnels with significant overburden, changeable geological conditions, a steep gradient, water infiltration, and heavy traffic flow are susceptible to environmental concerns during both construction and operation. The availability of fresh air and visibility is the most important necessity in excavation for tunnel workers inside the tunnel during the construction phase, as well as those crossing the tunnel during operation. Lowari Tunnel’s tunnel air pollutants were researched. Carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), hydrogen sulfide (H2S), sulfur dioxide (SO2), nitrogen oxide (NO), ammonia (NH3), nitrogen dioxide (NO2), PM1, PM2.5, PM10, air velocity, dust morphological and particle size distribution analysis are among the parameters under consideration. The findings provide evidence for the development of tunnel air quality.

This study presents a fuzzy analytic hierarchy process (FAHP) by integrating analytic hierarchy process (AHP) and fuzzy cognition to evaluate the construction risks of tunnel portals. Wuguanyi Tunnel is taken as the research objective to validate the performance of the proposed method. The result shows that the proposed decision making method can effectively identify risk factors and determine the risk level during the construction of tunnel portals. Finally, the corresponding control measures during the construction of the Wuguanyi Tunnel portal are proposed according to the risk assessment results.

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To study the safety and stability of the main truss arch structure during the concrete pouring process in a long-span CFST arch bridge, a combination of theoretical analysis and numerical simulation was adopted. The world's longest span CFST arch bridge, the Pingnan Third Bridge (main span 575 m) in Guangxi Province, was taken as an example. Firstly, the basic theory of stability and the concrete pouring technology of the main truss arch structure were summarized. Secondly, a three-dimensional finite element model of the main truss arch structure was established for the concrete pouring stage. Finally, the linearity, stress, and stability of the main truss arch structure during concrete pouring were studied. The results show that both vertical and transverse deflections occurred in the main truss arch structure during concrete pouring from the arch foot to the arch vault; the upper and transverse deflections of the main truss arch structure showed parabolic changes, and the upper and transverse deflections of the midspan section were larger than those of other sections. When concrete was poured near the 1/6 section of the main truss arch structure, the upper and transverse deflections of the middle section of the main truss arch structure peaked; the maximum upper deflection reached 113 mm, and the maximum transverse deflection reached 60 mm. In the process of concrete pouring from the arch foot to the arch vault, the stress in the steel tubes and concrete was constantly changing. Although upper and transverse deflections of the main truss arch structure occurred during concrete pouring, the stress in the steel tube and concrete in the main truss arch structure did not exceed the tensile strength, and the linearity of the main truss arch could be adjusted by retaining the anchor cables, which were set in the erection stage of the main truss arch structure at the 1/6 section of the main truss arch structure. During the concrete pouring process of the various steel tubes of the main truss arch structure, the stability coefficients of the main truss arch structures decreased gradually. During concrete pouring in a single steel tube, the maximum reduction in the stability factor was 21.32%, which occurred in the 1# steel tube, and the minimum decrease in the stability factor was 8.89%, which occurred in the 8# steel tube. The stability coefficients were greater than 4 after this reduction and met the requirements of the design specifications. This study can provide a reference for the optimization design and construction monitoring of long-span CFST arch bridges. [ABSTRACT FROM AUTHOR]

The occurrence of rockburst is related to the surrounding rock stress and geological rock mass strength. Rockburst occurs frequently during the construction at a deep tunnel in southwest China (a tunnel with a depth of approximately 2080 m, and a length of 13 km), leading to casualties, damage to construction equipment, and schedule delays. The application of the rockburst criteria based on the stress-strength/strength-stress ratio shows that they are not suitable for the construction stage. This paper suggests a simple and feasible rockburst intensity criterion based on the Geological Strength Index (GSI) for the construction stage. In this criterion, the strength of the rock mass exposed during excavation is estimated by the Hoek-Brown criterion and is used to reflect the geological conditions of the surrounding rock, considering the influences of the joint conditions and engineering disturbance. The maximum principal stress along the tunnel is obtained by the in situ stress inversion. The ratio of the rock mass strength to the maximum principal stress (σcm/σ1) is taken as the evaluation index. The criterion is as follows: σcm/σ1 > 1.2, none rockburst; 0.75 < σcm/σ1 ≤ 1.2, slight rockburst; 0.4 < σcm/σ1 ≤ 0.75, moderate rockburst; and σcm/σ1 ≤ 0.4, intense rockburst. The engineering applications show the reliability of this rockburst intensity criterion. The results of this paper provide a reference for rockburst intensity evaluation during the construction stage of deep tunnels. [ABSTRACT FROM AUTHOR]

The building industry is responsible for a large amount of waste, and the measurement and modelling of this waste could be used to develop better waste management plans. Several theoretical models explain the relationships between waste and building characteristics, but local practices may result in different behaviours. This study aimed to measure and analyse the waste generated through construction. It was based on the analysis of 18 building sites located in the region of Porto Alegre, Brazil. Waste was measured at these sites, and the results showed an average waste generation rate of 0.151 m3 m-2. A regression analysis of the collected data presented a satisfactory performance in two models. The first model was developed to explain total waste generation, including the effects of certain attributes, with an R2 = 0.81. The changes in waste generated during construction were estimated. The second model considered time schedules and examined the effect of the construction stage on waste generation, and reached an R2 = 0.91. The model with time indicated an S-shaped relationship. The models presented satisfactory statistical parameters and could be used to produce better waste management plans in the preconstruction stage. [ABSTRACT FROM AUTHOR]

The Longgang Bridge in Shaanxi, China, is a complex continuous hybrid structure composed of two cable-stayed self-anchored suspension parts and one single-pylon cable-stayed part. A 1:20-scaled model was established due to the effect of multiple structural transformation, frequent internal force changes during the construction process, and differences between actual material parameters and theoretical calculation parameters. In this paper, the design, materials, counterweight, experimental instrumentation, and construction stages of the scaled model are introduced. Based on the experimental data, the nonlinear behavior of the self-anchored suspension and cable-stayed hybrid bridge during the structural transformation of the construction process is systematically and comprehensively studied. The evolutions of the hanger force and stayed cable force, the variation in the subcable and back-cable forces, the displacement characteristics of the suspension cable and the deflection of the stiffened girder are analyzed, and the relationships among these variables in different states of the structural system are discussed. This paper will serve as a technical reference for the construction of similar bridges in the future. [ABSTRACT FROM AUTHOR]