The integration of Human-Robot Collaboration(HRC)into Virtual Reality(VR)technology is transforming industries by enhancing workforce skills,improving safety,and optimizing operational processes and efficiency through...The integration of Human-Robot Collaboration(HRC)into Virtual Reality(VR)technology is transforming industries by enhancing workforce skills,improving safety,and optimizing operational processes and efficiency through realistic simulations of industry-specific scenarios.Despite the growing adoption of VR integrated with HRC,comprehensive reviews of current research in HRC-VR within the construction and manufacturing fields are lacking.This review examines the latest advances in designing and implementing HRC using VR technology in these industries.The aim is to address the application domains of HRC-VR,types of robots used,VR setups,and software solutions used.To achieve this,a systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology was conducted on the Web of Science and Google Scholar databases,analyzing 383 articles and selecting 53 papers that met the established selection criteria.The findings emphasize a significant focus on enhancing human-robot interaction with a trend toward using immersive VR experiences and interactive 3D content creation tools.However,the integration of HRC with VR,especially in the dynamic construction environment,presents unique challenges and opportunities for future research,including developing more realistic simulations and adaptable robot systems.This paper offers insights for researchers,practitioners,educators,industry professionals,and policymakers interested in leveraging the integration of HRC with VR in construction and manufacturing industries.展开更多
The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertai...The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertainties. This study identifies 20 complexity factors through expert interviews and literature, categorising them into six groups. The Analytical Hierarchy Process evaluated the significance of different factors, establishing their corresponding weights to enhance adaptive project scheduling. A system dynamics (SD) model is developed and tested to evaluate the dynamic behaviour of identified complexity factors. The model simulates the impact of complexity on total project duration (TPD), revealing significant deviations from initial deterministic estimates. Data collection and analysis for reliability tests, including normality and Cronbach alpha, to validate the model’s components and expert feedback. Sensitivity analysis confirmed a positive relationship between complexity and project duration, with higher complexity levels resulting in increased TPD. This relationship highlights the inadequacy of static planning approaches and underscores the importance of addressing complexity dynamically. The study provides a framework for enhancing planning systems through system dynamics and recommends expanding the model to ensure broader applicability in diverse construction projects.展开更多
In order to increase the productivity of construction industry, emerging technologies have been constantly introduced and applied in this traditional industry by pilot researchers. This paper provides an integrated mo...In order to increase the productivity of construction industry, emerging technologies have been constantly introduced and applied in this traditional industry by pilot researchers. This paper provides an integrated model of radio-frequency identification (RFID) and four-dimensional Computer-Aided Design (4D CAD) in construction management. RFID involves the use of tags that collect data and transmit data. RFID can collect data by radio waves instead of light waves. RFID technology is surpassing barcode technology where light waves are easily blocked and barcode labels are easy to fall off or become unreadable due to dust, dirt, or other contaminants. 4D CAD which involves 3D construction models and construction schedules presents visualized construction process. Integration of RFID and 4D CAD in this paper built a dynamic construction management and control system which would reduce the time of capturing data on site and control quality of construction materials efficiently. Pilot test result shows that a construction manager can easily understand how and what a complicated construction project will be accomplished. Although further analysis is necessary, RFID and 4D CAD show promises of being a beneficial technology in construction management.展开更多
The construction of megaprojects has always resulted in extensive and long-term impacts on the society.However,the performance of megaproject management is poor,and improving it remains an urgent and necessary issue.A...The construction of megaprojects has always resulted in extensive and long-term impacts on the society.However,the performance of megaproject management is poor,and improving it remains an urgent and necessary issue.Although many studies on megaproject success have been conducted,existing studies on the driving factors of successful megaproject construction are rather limited.Therefore,this study aims to systematically explore the key factors that can lead to successful megaproject construction management based on three cases:The Beijing-Shanghai High-Speed Railway,the Three Gorges Dam,and the Hong Kong-Zhuhai-Macao Bridge.Mixed research methods,such as literature review,case studies,and expert interviews,were used in this study.Consequently,11 driving factors,namely,government support,public support,accumulation and application of technology and experience,development and innovation of technology,innovation and application of management system,organizational mode and structure,top management support,project culture,megaproject citizenship behavior,corporate reputation,and fulfillment of social responsibilities,were identified and grouped into five categories,namely,project environment,construction capabilities,organization,positive culture and behavior,and requirements for sustainable development.The contributions of this study lie in two aspects.First,the driving factors of successful megaproject construction are identified to deepen the understanding of industrial practitioners,assist them in focusing on key factors,and aid them in effectively managing megaprojects.Second,researchers could use the identified driving factors in conducting further empirical studies and apply them in future projects to enhance their chances of success.展开更多
Completing the principal engineering components of a pumped storage power station spans between 50 and 60 months,from the inception of construction to the commencement of power generation by the first unit.The filling...Completing the principal engineering components of a pumped storage power station spans between 50 and 60 months,from the inception of construction to the commencement of power generation by the first unit.The filling of the penstock with water represents a critical phase preceding the production of electricity by the first unit.During this interval,the construction of the diversion shaft presents multiple challenges,including intricate construction procedures,considerable construction difficulty,elevated safety risks,and quality control issues.To address this issue,this study uses CFD software to analyze the flow field,pressure gradient,and head loss of shaft curved section with different curvature radius,and examines several key technologies by drawing on the practice of diversion shaft construction at the Meizhou pumped storage power station.These technologies include optimizing the curvature radius of the curved section of diversion shaft,reverse-well excavation for the shaft,and sliding-up for the lining concrete.It is found that as the curvature radius of shaft curved section reduces from 4 to 2 times the shaft diameter,the hydraulic characteristic index does not change much,and the increase of head loss accounts for about 0.18%of the total head loss of the water conveyance system.The result show that optimizing the curvature radius from 4 times to 2 times the shaft diameter is feasible and reasonable,and several improved technical measures have been proposed,such as stabilizing drill rods,mechanical scraper systems,and control technology of the relationship between concrete setting time and formwork sliding.Their implementation effectively mitigates difficulties and safety risks during shaft construction,expedites the project schedule,enhances engineering quality,and creates a 41-month timeline for the principal engineering schedule for the first power unit generation in China.展开更多
Construction companies face threats from competition and must be able to adjust to modem technology and changes in customer expectations. These issues require efficient risk management techniques. The success of const...Construction companies face threats from competition and must be able to adjust to modem technology and changes in customer expectations. These issues require efficient risk management techniques. The success of construction companies running projects in international markets depends on how the risks arise from the host country conditions as well as the project specific risk factors. Successful management of risks requires identification of risks, construction of a risk model which can be used to assess the magnitude of risks, and implementation of response strategies so that an acceptable risk-return balance can be achieved. The project success usually depends on the combination of all risks, response strategies used to mitigate risks, and a company＇s ability to manage them. There exists a need to develop risk models containing the risks of doing business in international markets and factors that affect manageability of these risks. One of the market＇s critical challenges is scheduled management and the understanding and application of program management. This paper uses systematic risk identification, classification and analysis, and measurement and response methodologies to help international contractors quantify the risks of project development and accomplishment.展开更多
Based on the general high-quality development requirements for railway construction in the new era,combined with the new concept of railway passenger stations of China State Railway Group Co.Ltd,namely"being well...Based on the general high-quality development requirements for railway construction in the new era,combined with the new concept of railway passenger stations of China State Railway Group Co.Ltd,namely"being well-connected,fully-integrated,environmeni-friendlypassenger-oriented,economically-efficient,culturally-rich,intelligent and convenient"and aiming at the construction of exemplary passenger station projects,this paper summarizes the construction experience in construction,decoration furnishing culture and art expression of railway passenger stations,proposes the working patterns of formulating the implementation plans of exemplary railway passenger station projects and the expert reviews in innovative way studies and forms 6 special-subject designs such as for colorshape,space,environment,art and culture,as wellas the specific design requirements for 13 key areas including waiting hall entrance and exit corridor;VIP room,etc.,and summarizes and puts forward the construction management system of railway passenger stations in the new era,so as to ensure the expected exemplary project quality of railway passenger stations.展开更多
The purpose of this study was to assess the acceptance of a model of construction and demolition waste-minimization practices by construction management senior students.This approach assumed students can informally in...The purpose of this study was to assess the acceptance of a model of construction and demolition waste-minimization practices by construction management senior students.This approach assumed students can informally influence construction industry opinions,making their decisions vital to future construction-management education standards.The capstone class of the bachelor’s degree program of one of the foremost construction management programs in the country was the sample chosen to study.It was found that a majority of the students were knowledgeable about all of the practices and had favorable opinions based on that knowledge.Most had tried more than half of the practices on a limited basis and decided they would use the practices based on these trials.The largest part of the students did not have experience applying a good number of the practices;however,almost all of those with this experience would continue to use all the practices.Identifying successful trial and application experiences and asking students how they became involved in such experiences would be useful in the implementation of a school plan to increase acceptance.展开更多
Construction safety management is the key work to ensure the overall construction quality. At present, some construction enterprises do not have a complete safety management system, the person in charge of the lack of...Construction safety management is the key work to ensure the overall construction quality. At present, some construction enterprises do not have a complete safety management system, the person in charge of the lack of safety management awareness, which is not conducive to the development of construction safety control work. In order to reduce the occurrence of safety accidents to the maximum extent, the construction leaders of construction enterprise also need to formulate reasonable and effective safety control regulations according to the construction site, and manage construction equipment and construction personnel scientifically. At the same time, relevant technical personnel of construction enterprises should also introduce new technologies and equipment related to production and reduce the direct contact of construction personnel to high-risk facilities, so as to promote the stable development of construction work under the premise of ensuring safety.展开更多
This paper introduces the research on construction quality management of OD 1422mX80 pipeline project. OD1422mm X80 pipe has been applied in the east line natural gas pipeline project between China and Russia for the ...This paper introduces the research on construction quality management of OD 1422mX80 pipeline project. OD1422mm X80 pipe has been applied in the east line natural gas pipeline project between China and Russia for the first time. Through the research on the establishment of the quality system, process control and target evaluation of the east line pipeline between China and Russia, it can provide reference and reference for the construction quality management of OD 1422 mm X80 pipeline project in the future.展开更多
The demand for monitoring activities has been more evident recently in oil and gas“O&G”activities such as exploration,drilling,production,logistics,or shipping.Consequently,these offshore infrastructures require...The demand for monitoring activities has been more evident recently in oil and gas“O&G”activities such as exploration,drilling,production,logistics,or shipping.Consequently,these offshore infrastructures require asset management(or facilities management).This study seeks to understand the research pattern of publications within the domain of asset management in offshore infrastructures with the aim of determining the present state of the field’s research.The paper conducts a scientometric analysis of publications that focus on offshore infrastructures’asset management published between 1992 and 2022.The employed search query yielded a total of 346 journal articles from the Scopus database and 43 from the Web of Science(WoS)database,respectively.The data analysis of the scientometric investigation explored research authorship,co-occurrence of keywords,number of publications,network mapping,country geographical breakdown,and literature coupling.The paper shows rising interest in monitoring and asset management in the oil and gas industry.It was concluded that the management of these infrastructures requires frequent review with the application of sustainable asset management strategies.展开更多
Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characterist...Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characteristics.The composition of the cement-based material,including the type of cement and auxiliary materials,greatly influences the ability of the material to bind Cl^(-),and varied components result in varying binding beha-vior of the Cl^(-).Simultaneously,the Cl^(-)binding process in concrete is influenced by both the internal and exterior surroundings,as well as the curing practices.These factors impact the hydration process of the cement and the internal pore structure of the concrete.Currently,mathematical theories and molecular dynamics simulations have increasingly been employed as the prevalent methods for examining the binding behaviors of Cl^(-)in concrete.These techniques are extensively utilized for predicting the lifespan and conducting microscopic studies of reinforced concrete in Cl^(-)settings.This work proposes recommendations for future research based on a summary of experimental and simulation investigations on Cl^(-)binding.Which will offer theoretical guidance for studying the binding of Cl^(-)in cement-based materials.展开更多
The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition...The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance.展开更多
Although currently,a large part of the existing buildings is considered inefficient in terms of energy,the ability to save energy consumption up to 80%has been proven in residential and commercial buildings.Also,carbo...Although currently,a large part of the existing buildings is considered inefficient in terms of energy,the ability to save energy consumption up to 80%has been proven in residential and commercial buildings.Also,carbon dioxide is one of the most important greenhouse gases contributing to climate change and is responsible for 60%of global warming.The facade of the building,as the main intermediary between the interior and exterior spaces,plays a significant role in adjusting the weather conditions and providing thermal comfort to the residents.In this research,715 different scenarios were defined with the combination of various types of construction materials,and the effect of each of these scenarios on the process of energy loss from the surface of the external walls of the building during the operation period was determined.In the end,these scenarios were compared during a one-year operation period,and the amount of energy consumption in each of these scenarios was calculated.Also,bymeasuring the amount of carbon emissions in buildings during the operation period and before that,let’s look at practical methods to reduce the effects of the construction industry on the environment.By comparing the research findings,it can be seen that the ranking of each scenario in terms of total energy consumption is not necessarily the same as the ranking of energy consumption for gas consumption or electricity consumption for the same scenario.That is,choosing the optimal scenario depends on the type of energy consumed in the building.Finally,we determined the scenarios with the lowest and highest amounts of embodied and operational carbon.In the end,we obtained the latent carbon compensation period for each scenario.This article can help designers and construction engineers optimize the energy consumption of buildings by deciding on the right materials.展开更多
The addition of nanoparticles serves as an effective reinforcement strategy for polymeric coatings,utilizing their unique characteristics as well as extraordinary mechanical,thermal,and electrical properties.The excep...The addition of nanoparticles serves as an effective reinforcement strategy for polymeric coatings,utilizing their unique characteristics as well as extraordinary mechanical,thermal,and electrical properties.The exceptionally high surface-to-volume ratio of nanoparticles imparts remarkable reinforcing potentials,yet it simultaneously gives rise to a prevalent tendency for nanoparticles to agglomerate into clusters within nanocomposites.The agglomeration behavior of the nanoparticles is predominantly influenced by their distinct microstructures and varied weight concentrations.This study investigated the synergistic effects of nanoparticle geometric shape and weight concentration on the dispersion characteristics of nanoparticles and the physical-mechanical performances of nano-reinforced epoxy coatings.Three carbon-based nanoparticles,nanodiamonds(NDs),carbon nanotubes(CNTs),and graphenes(GNPs),were incorporated into epoxy coatings at three weight concentrations(0.5%,1.0%,and 2.0%).The experimental findings reveal that epoxy coatings reinforced with NDs demonstrated the most homogenous dispersion characteristics,lowest viscosity,and reduced porosity among all the nanoparticles,which could be attributed to the spherical geometry shape.Due to the superior physical properties,ND-reinforced nanocomposites displayed the highest abrasion resistance and tensile properties.Specifically,the 1.0wt%ND-reinforced nanocomposites exhibited 60%,52%,and 97%improvements in mass lost,tensile strength,and failure strain,respectively,compared to pure epoxy.Furthermore,the representative volume element(RVE)modeling was employed to validate the experimental results,while highlighting the critical role of nanoparticle agglomeration,orientation,and the presence of voids on the mechanical properties of the nanocomposites.Nano-reinforced epoxy coatings with enhanced mechanical properties are well-suited for application in protective coatings for pipelines,industrial equipment,and automotive parts,where high wear resistance is essential.展开更多
A steel-concrete composite cable-stayed bridge features integrated steel girders and concrete decks linked by shear connectors to support loads,but stress concentration in wet joints can lead to cracking.In-situ tests...A steel-concrete composite cable-stayed bridge features integrated steel girders and concrete decks linked by shear connectors to support loads,but stress concentration in wet joints can lead to cracking.In-situ tests were conducted on key sections of steel-concrete composite cable-stayed bridges to analyze the stress-strain evolution of wet joints under environmental factors,constraints,and complex construction processes.The coordinated working performance of the bridge decks was also analyzed.The results indicate that temperature is the key factor affecting the stresses and strains in wet joint concrete.Approximately 7 days after casting the wet joint concrete,the strains at each measurement point of the wet joint are approximately negatively correlated with the temperature change at the measurement point.Different locations within the wet joints have respective impacts,presenting potential weak points.Construction conditions have a certain impact on the stress and strain of the wet joint.The top deck of the steel box girder is not fully bonded to the bottom surface of the wet joints,resulting in a certain strain difference after loading.To further analyze the cooperative working performance of steel box girders and concrete wet joint bridge deck systems,finite element analysis was conducted on composite girder structures.A stiffness calculation method for shear connectors based on numerical simulation was proposed.The results indicate that strain differences can cause interface slip in composite girders.This slip leads to increased deflection of the composite girders and increased tensile stress in the bottom plate of the steel box girders.This study clarifies the stress conditions and factors affecting wet joints during construction,preventing early cracking,and offers precise data for a full bridge finite element model.展开更多
Internet of Things(IoT)technology has brought about significant new changes to residents’lives,prompting changes in management models across various industries and promoting the overall intelligence of urban construc...Internet of Things(IoT)technology has brought about significant new changes to residents’lives,prompting changes in management models across various industries and promoting the overall intelligence of urban construction.Especially in the context of continuous technological development,information sensor devices can be effectively utilized to connect multiple dimensions in urban construction,enhancing the intelligence level of cities in China.This paper mainly elaborates on the application significance of IoT technology in smart cities and proposes corresponding measures from aspects such as smart transportation systems,intelligent public utility management,urban safety and monitoring,environmental monitoring,and sustainability,providing references for relevant personnel.展开更多
The rapid development of Internet technology has made“Internet+”a hallmark of the current era.The transformation and development of traditional media into all-media have provided a guiding direction for the developm...The rapid development of Internet technology has made“Internet+”a hallmark of the current era.The transformation and development of traditional media into all-media have provided a guiding direction for the development of campus media.The traditional form of campus media,which mainly consists of campus newspapers and campus radio,can no longer meet the application demands of modern higher education for media.In line with the current media convergence environment,campus media need to actively innovate to achieve their own development and progress in keeping with the times.This article explores the innovation path of campus media in the context of media convergence,analyzing the promotion of campus media innovation by the development of new media,the diversification of campus media innovation,and the effective ways of campus media innovation,in order to promote the realization of the innovation and development goals of campus media in the context of media convergence.展开更多
Roadside habitat through major urban areas may offer remnant examples of natural grasslands.These habitats may be subjected to frequent as mowing and exposure to automobile emissions and runoff.This study was conducte...Roadside habitat through major urban areas may offer remnant examples of natural grasslands.These habitats may be subjected to frequent as mowing and exposure to automobile emissions and runoff.This study was conducted on interstate highway right-of-ways in San Antonio,Texas,U.S.A.We compared the vegetation species and diversity,and the organic carbon of leaf litter,plants,and soils.Two non-native grasses accounted for 50.9% cover,while all native forbs and grasses accounted for only 9.8% cover.The mean biomass of nonnative grasseswas 4.5 times greater than that of all native species.Organic carbon content of leaf litter,plants,and soils was variable among the study sites,possibly due to management practices and a drought that occurred during the study.Themean organic carbon content in the upper 20 cm soil was 5.0 kg C/m^(2) and organic carbon content was greater in the upper 10 cm than organic carbon in the 10.1 to 20 cm portion.Cynodon dactylon and Bouteloua curtipendula exhibited the greatest photosynthesis efficiency indicating these grasses are more adaptable to hot summer temperatures found in Central Texas.The organic carbon content along a major interstate was 13,793 kg·C/ha for leaf litter,vegetation,and the upper 20 cm of the soil.We conclude that interstate highways provide habitat for some native species,but the vegetation along right-of-ways is dominated by two non-native grasses.It appears unlikely that roadside habitat can be restored to resemble native grasslands without large scale and costly restoration efforts.展开更多
The green retrofit of existing public buildings is a necessary choice to promote energy conservation,emission reduction,and sustainable development goals in the construction industry,and to advance the implementation ...The green retrofit of existing public buildings is a necessary choice to promote energy conservation,emission reduction,and sustainable development goals in the construction industry,and to advance the implementation of the national"carbon peaking and carbon neutrality"strategy.The effective governance of green retrofit projects for existing public buildings essentially involves a dynamic process of repeated strategic interactions among key stakeholders.From the perspective of project governance,this study clarifies the game-theoretic relationship between ESCO and owners under government guidance,and constructs an evolutionary game model involving the government,ESCO,and owners.The study explores the strategic choices of the core stakeholders in the green retrofit projects of existing public buildings.The aim is to lay a foundation for research on the decision-making coordination and implementation mechanisms between ESCO and owners,thus promoting the efficient and healthy development of green retrofit projects for existing public buildings.展开更多
基金Supported by National Science Foundation under Grant No.2222881.
文摘The integration of Human-Robot Collaboration(HRC)into Virtual Reality(VR)technology is transforming industries by enhancing workforce skills,improving safety,and optimizing operational processes and efficiency through realistic simulations of industry-specific scenarios.Despite the growing adoption of VR integrated with HRC,comprehensive reviews of current research in HRC-VR within the construction and manufacturing fields are lacking.This review examines the latest advances in designing and implementing HRC using VR technology in these industries.The aim is to address the application domains of HRC-VR,types of robots used,VR setups,and software solutions used.To achieve this,a systematic literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology was conducted on the Web of Science and Google Scholar databases,analyzing 383 articles and selecting 53 papers that met the established selection criteria.The findings emphasize a significant focus on enhancing human-robot interaction with a trend toward using immersive VR experiences and interactive 3D content creation tools.However,the integration of HRC with VR,especially in the dynamic construction environment,presents unique challenges and opportunities for future research,including developing more realistic simulations and adaptable robot systems.This paper offers insights for researchers,practitioners,educators,industry professionals,and policymakers interested in leveraging the integration of HRC with VR in construction and manufacturing industries.
文摘The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertainties. This study identifies 20 complexity factors through expert interviews and literature, categorising them into six groups. The Analytical Hierarchy Process evaluated the significance of different factors, establishing their corresponding weights to enhance adaptive project scheduling. A system dynamics (SD) model is developed and tested to evaluate the dynamic behaviour of identified complexity factors. The model simulates the impact of complexity on total project duration (TPD), revealing significant deviations from initial deterministic estimates. Data collection and analysis for reliability tests, including normality and Cronbach alpha, to validate the model’s components and expert feedback. Sensitivity analysis confirmed a positive relationship between complexity and project duration, with higher complexity levels resulting in increased TPD. This relationship highlights the inadequacy of static planning approaches and underscores the importance of addressing complexity dynamically. The study provides a framework for enhancing planning systems through system dynamics and recommends expanding the model to ensure broader applicability in diverse construction projects.
文摘In order to increase the productivity of construction industry, emerging technologies have been constantly introduced and applied in this traditional industry by pilot researchers. This paper provides an integrated model of radio-frequency identification (RFID) and four-dimensional Computer-Aided Design (4D CAD) in construction management. RFID involves the use of tags that collect data and transmit data. RFID can collect data by radio waves instead of light waves. RFID technology is surpassing barcode technology where light waves are easily blocked and barcode labels are easy to fall off or become unreadable due to dust, dirt, or other contaminants. 4D CAD which involves 3D construction models and construction schedules presents visualized construction process. Integration of RFID and 4D CAD in this paper built a dynamic construction management and control system which would reduce the time of capturing data on site and control quality of construction materials efficiently. Pilot test result shows that a construction manager can easily understand how and what a complicated construction project will be accomplished. Although further analysis is necessary, RFID and 4D CAD show promises of being a beneficial technology in construction management.
基金This study was funded by the National Natural Science Foundation of China(Grant Nos.71971161 and 71390523).
文摘The construction of megaprojects has always resulted in extensive and long-term impacts on the society.However,the performance of megaproject management is poor,and improving it remains an urgent and necessary issue.Although many studies on megaproject success have been conducted,existing studies on the driving factors of successful megaproject construction are rather limited.Therefore,this study aims to systematically explore the key factors that can lead to successful megaproject construction management based on three cases:The Beijing-Shanghai High-Speed Railway,the Three Gorges Dam,and the Hong Kong-Zhuhai-Macao Bridge.Mixed research methods,such as literature review,case studies,and expert interviews,were used in this study.Consequently,11 driving factors,namely,government support,public support,accumulation and application of technology and experience,development and innovation of technology,innovation and application of management system,organizational mode and structure,top management support,project culture,megaproject citizenship behavior,corporate reputation,and fulfillment of social responsibilities,were identified and grouped into five categories,namely,project environment,construction capabilities,organization,positive culture and behavior,and requirements for sustainable development.The contributions of this study lie in two aspects.First,the driving factors of successful megaproject construction are identified to deepen the understanding of industrial practitioners,assist them in focusing on key factors,and aid them in effectively managing megaprojects.Second,researchers could use the identified driving factors in conducting further empirical studies and apply them in future projects to enhance their chances of success.
文摘Completing the principal engineering components of a pumped storage power station spans between 50 and 60 months,from the inception of construction to the commencement of power generation by the first unit.The filling of the penstock with water represents a critical phase preceding the production of electricity by the first unit.During this interval,the construction of the diversion shaft presents multiple challenges,including intricate construction procedures,considerable construction difficulty,elevated safety risks,and quality control issues.To address this issue,this study uses CFD software to analyze the flow field,pressure gradient,and head loss of shaft curved section with different curvature radius,and examines several key technologies by drawing on the practice of diversion shaft construction at the Meizhou pumped storage power station.These technologies include optimizing the curvature radius of the curved section of diversion shaft,reverse-well excavation for the shaft,and sliding-up for the lining concrete.It is found that as the curvature radius of shaft curved section reduces from 4 to 2 times the shaft diameter,the hydraulic characteristic index does not change much,and the increase of head loss accounts for about 0.18%of the total head loss of the water conveyance system.The result show that optimizing the curvature radius from 4 times to 2 times the shaft diameter is feasible and reasonable,and several improved technical measures have been proposed,such as stabilizing drill rods,mechanical scraper systems,and control technology of the relationship between concrete setting time and formwork sliding.Their implementation effectively mitigates difficulties and safety risks during shaft construction,expedites the project schedule,enhances engineering quality,and creates a 41-month timeline for the principal engineering schedule for the first power unit generation in China.
文摘Construction companies face threats from competition and must be able to adjust to modem technology and changes in customer expectations. These issues require efficient risk management techniques. The success of construction companies running projects in international markets depends on how the risks arise from the host country conditions as well as the project specific risk factors. Successful management of risks requires identification of risks, construction of a risk model which can be used to assess the magnitude of risks, and implementation of response strategies so that an acceptable risk-return balance can be achieved. The project success usually depends on the combination of all risks, response strategies used to mitigate risks, and a company＇s ability to manage them. There exists a need to develop risk models containing the risks of doing business in international markets and factors that affect manageability of these risks. One of the market＇s critical challenges is scheduled management and the understanding and application of program management. This paper uses systematic risk identification, classification and analysis, and measurement and response methodologies to help international contractors quantify the risks of project development and accomplishment.
文摘Based on the general high-quality development requirements for railway construction in the new era,combined with the new concept of railway passenger stations of China State Railway Group Co.Ltd,namely"being well-connected,fully-integrated,environmeni-friendlypassenger-oriented,economically-efficient,culturally-rich,intelligent and convenient"and aiming at the construction of exemplary passenger station projects,this paper summarizes the construction experience in construction,decoration furnishing culture and art expression of railway passenger stations,proposes the working patterns of formulating the implementation plans of exemplary railway passenger station projects and the expert reviews in innovative way studies and forms 6 special-subject designs such as for colorshape,space,environment,art and culture,as wellas the specific design requirements for 13 key areas including waiting hall entrance and exit corridor;VIP room,etc.,and summarizes and puts forward the construction management system of railway passenger stations in the new era,so as to ensure the expected exemplary project quality of railway passenger stations.
文摘The purpose of this study was to assess the acceptance of a model of construction and demolition waste-minimization practices by construction management senior students.This approach assumed students can informally influence construction industry opinions,making their decisions vital to future construction-management education standards.The capstone class of the bachelor’s degree program of one of the foremost construction management programs in the country was the sample chosen to study.It was found that a majority of the students were knowledgeable about all of the practices and had favorable opinions based on that knowledge.Most had tried more than half of the practices on a limited basis and decided they would use the practices based on these trials.The largest part of the students did not have experience applying a good number of the practices;however,almost all of those with this experience would continue to use all the practices.Identifying successful trial and application experiences and asking students how they became involved in such experiences would be useful in the implementation of a school plan to increase acceptance.
文摘Construction safety management is the key work to ensure the overall construction quality. At present, some construction enterprises do not have a complete safety management system, the person in charge of the lack of safety management awareness, which is not conducive to the development of construction safety control work. In order to reduce the occurrence of safety accidents to the maximum extent, the construction leaders of construction enterprise also need to formulate reasonable and effective safety control regulations according to the construction site, and manage construction equipment and construction personnel scientifically. At the same time, relevant technical personnel of construction enterprises should also introduce new technologies and equipment related to production and reduce the direct contact of construction personnel to high-risk facilities, so as to promote the stable development of construction work under the premise of ensuring safety.
文摘This paper introduces the research on construction quality management of OD 1422mX80 pipeline project. OD1422mm X80 pipe has been applied in the east line natural gas pipeline project between China and Russia for the first time. Through the research on the establishment of the quality system, process control and target evaluation of the east line pipeline between China and Russia, it can provide reference and reference for the construction quality management of OD 1422 mm X80 pipeline project in the future.
基金The School of Engineering,Lancaster University,UK and the Engineering and Physical Sciences Research Council(EPSRC)’s Doctoral Training Centre(DTC),UK are highly appreciatedMoreso,the Foreign Postgraduate Scholarship of Niger Delta Development Commission(NDDC)Nigeria are also valued for financial support as well as the BOLD25 Initiative of Universiti Tenaga Nasional(UNITEN),Malaysia.
文摘The demand for monitoring activities has been more evident recently in oil and gas“O&G”activities such as exploration,drilling,production,logistics,or shipping.Consequently,these offshore infrastructures require asset management(or facilities management).This study seeks to understand the research pattern of publications within the domain of asset management in offshore infrastructures with the aim of determining the present state of the field’s research.The paper conducts a scientometric analysis of publications that focus on offshore infrastructures’asset management published between 1992 and 2022.The employed search query yielded a total of 346 journal articles from the Scopus database and 43 from the Web of Science(WoS)database,respectively.The data analysis of the scientometric investigation explored research authorship,co-occurrence of keywords,number of publications,network mapping,country geographical breakdown,and literature coupling.The paper shows rising interest in monitoring and asset management in the oil and gas industry.It was concluded that the management of these infrastructures requires frequent review with the application of sustainable asset management strategies.
文摘Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characteristics.The composition of the cement-based material,including the type of cement and auxiliary materials,greatly influences the ability of the material to bind Cl^(-),and varied components result in varying binding beha-vior of the Cl^(-).Simultaneously,the Cl^(-)binding process in concrete is influenced by both the internal and exterior surroundings,as well as the curing practices.These factors impact the hydration process of the cement and the internal pore structure of the concrete.Currently,mathematical theories and molecular dynamics simulations have increasingly been employed as the prevalent methods for examining the binding behaviors of Cl^(-)in concrete.These techniques are extensively utilized for predicting the lifespan and conducting microscopic studies of reinforced concrete in Cl^(-)settings.This work proposes recommendations for future research based on a summary of experimental and simulation investigations on Cl^(-)binding.Which will offer theoretical guidance for studying the binding of Cl^(-)in cement-based materials.
基金supported by National Natural Science Foundations of China(nos.12271326,62102304,61806120,61502290,61672334,61673251)China Postdoctoral Science Foundation(no.2015M582606)+2 种基金Industrial Research Project of Science and Technology in Shaanxi Province(nos.2015GY016,2017JQ6063)Fundamental Research Fund for the Central Universities(no.GK202003071)Natural Science Basic Research Plan in Shaanxi Province of China(no.2022JM-354).
文摘The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance.
文摘Although currently,a large part of the existing buildings is considered inefficient in terms of energy,the ability to save energy consumption up to 80%has been proven in residential and commercial buildings.Also,carbon dioxide is one of the most important greenhouse gases contributing to climate change and is responsible for 60%of global warming.The facade of the building,as the main intermediary between the interior and exterior spaces,plays a significant role in adjusting the weather conditions and providing thermal comfort to the residents.In this research,715 different scenarios were defined with the combination of various types of construction materials,and the effect of each of these scenarios on the process of energy loss from the surface of the external walls of the building during the operation period was determined.In the end,these scenarios were compared during a one-year operation period,and the amount of energy consumption in each of these scenarios was calculated.Also,bymeasuring the amount of carbon emissions in buildings during the operation period and before that,let’s look at practical methods to reduce the effects of the construction industry on the environment.By comparing the research findings,it can be seen that the ranking of each scenario in terms of total energy consumption is not necessarily the same as the ranking of energy consumption for gas consumption or electricity consumption for the same scenario.That is,choosing the optimal scenario depends on the type of energy consumed in the building.Finally,we determined the scenarios with the lowest and highest amounts of embodied and operational carbon.In the end,we obtained the latent carbon compensation period for each scenario.This article can help designers and construction engineers optimize the energy consumption of buildings by deciding on the right materials.
基金supported by the National Science Foundation(NSF)(No.CMMI-1750316)Pipeline and Hazardous Materials Safety Administration(PHMSA)of U.S.Department of Transportation(No.693JK31950008CAAP).
文摘The addition of nanoparticles serves as an effective reinforcement strategy for polymeric coatings,utilizing their unique characteristics as well as extraordinary mechanical,thermal,and electrical properties.The exceptionally high surface-to-volume ratio of nanoparticles imparts remarkable reinforcing potentials,yet it simultaneously gives rise to a prevalent tendency for nanoparticles to agglomerate into clusters within nanocomposites.The agglomeration behavior of the nanoparticles is predominantly influenced by their distinct microstructures and varied weight concentrations.This study investigated the synergistic effects of nanoparticle geometric shape and weight concentration on the dispersion characteristics of nanoparticles and the physical-mechanical performances of nano-reinforced epoxy coatings.Three carbon-based nanoparticles,nanodiamonds(NDs),carbon nanotubes(CNTs),and graphenes(GNPs),were incorporated into epoxy coatings at three weight concentrations(0.5%,1.0%,and 2.0%).The experimental findings reveal that epoxy coatings reinforced with NDs demonstrated the most homogenous dispersion characteristics,lowest viscosity,and reduced porosity among all the nanoparticles,which could be attributed to the spherical geometry shape.Due to the superior physical properties,ND-reinforced nanocomposites displayed the highest abrasion resistance and tensile properties.Specifically,the 1.0wt%ND-reinforced nanocomposites exhibited 60%,52%,and 97%improvements in mass lost,tensile strength,and failure strain,respectively,compared to pure epoxy.Furthermore,the representative volume element(RVE)modeling was employed to validate the experimental results,while highlighting the critical role of nanoparticle agglomeration,orientation,and the presence of voids on the mechanical properties of the nanocomposites.Nano-reinforced epoxy coatings with enhanced mechanical properties are well-suited for application in protective coatings for pipelines,industrial equipment,and automotive parts,where high wear resistance is essential.
文摘A steel-concrete composite cable-stayed bridge features integrated steel girders and concrete decks linked by shear connectors to support loads,but stress concentration in wet joints can lead to cracking.In-situ tests were conducted on key sections of steel-concrete composite cable-stayed bridges to analyze the stress-strain evolution of wet joints under environmental factors,constraints,and complex construction processes.The coordinated working performance of the bridge decks was also analyzed.The results indicate that temperature is the key factor affecting the stresses and strains in wet joint concrete.Approximately 7 days after casting the wet joint concrete,the strains at each measurement point of the wet joint are approximately negatively correlated with the temperature change at the measurement point.Different locations within the wet joints have respective impacts,presenting potential weak points.Construction conditions have a certain impact on the stress and strain of the wet joint.The top deck of the steel box girder is not fully bonded to the bottom surface of the wet joints,resulting in a certain strain difference after loading.To further analyze the cooperative working performance of steel box girders and concrete wet joint bridge deck systems,finite element analysis was conducted on composite girder structures.A stiffness calculation method for shear connectors based on numerical simulation was proposed.The results indicate that strain differences can cause interface slip in composite girders.This slip leads to increased deflection of the composite girders and increased tensile stress in the bottom plate of the steel box girders.This study clarifies the stress conditions and factors affecting wet joints during construction,preventing early cracking,and offers precise data for a full bridge finite element model.
文摘Internet of Things(IoT)technology has brought about significant new changes to residents’lives,prompting changes in management models across various industries and promoting the overall intelligence of urban construction.Especially in the context of continuous technological development,information sensor devices can be effectively utilized to connect multiple dimensions in urban construction,enhancing the intelligence level of cities in China.This paper mainly elaborates on the application significance of IoT technology in smart cities and proposes corresponding measures from aspects such as smart transportation systems,intelligent public utility management,urban safety and monitoring,environmental monitoring,and sustainability,providing references for relevant personnel.
文摘The rapid development of Internet technology has made“Internet+”a hallmark of the current era.The transformation and development of traditional media into all-media have provided a guiding direction for the development of campus media.The traditional form of campus media,which mainly consists of campus newspapers and campus radio,can no longer meet the application demands of modern higher education for media.In line with the current media convergence environment,campus media need to actively innovate to achieve their own development and progress in keeping with the times.This article explores the innovation path of campus media in the context of media convergence,analyzing the promotion of campus media innovation by the development of new media,the diversification of campus media innovation,and the effective ways of campus media innovation,in order to promote the realization of the innovation and development goals of campus media in the context of media convergence.
基金supported by the Transportation Consortium of South-Central States (No.18HSTSA01)support was provided by the University of San Antonio, Department of Integrated Biology from the principal investigator’s startup funds to support student research assistants.
文摘Roadside habitat through major urban areas may offer remnant examples of natural grasslands.These habitats may be subjected to frequent as mowing and exposure to automobile emissions and runoff.This study was conducted on interstate highway right-of-ways in San Antonio,Texas,U.S.A.We compared the vegetation species and diversity,and the organic carbon of leaf litter,plants,and soils.Two non-native grasses accounted for 50.9% cover,while all native forbs and grasses accounted for only 9.8% cover.The mean biomass of nonnative grasseswas 4.5 times greater than that of all native species.Organic carbon content of leaf litter,plants,and soils was variable among the study sites,possibly due to management practices and a drought that occurred during the study.Themean organic carbon content in the upper 20 cm soil was 5.0 kg C/m^(2) and organic carbon content was greater in the upper 10 cm than organic carbon in the 10.1 to 20 cm portion.Cynodon dactylon and Bouteloua curtipendula exhibited the greatest photosynthesis efficiency indicating these grasses are more adaptable to hot summer temperatures found in Central Texas.The organic carbon content along a major interstate was 13,793 kg·C/ha for leaf litter,vegetation,and the upper 20 cm of the soil.We conclude that interstate highways provide habitat for some native species,but the vegetation along right-of-ways is dominated by two non-native grasses.It appears unlikely that roadside habitat can be restored to resemble native grasslands without large scale and costly restoration efforts.
基金supported by the National Natural Science Foundation of China(Grant No.71872122)the Late-stage Subsidy Project of Humanities and Social Sciences of the Education Department of China(Grant No.20JHQ095).
文摘The green retrofit of existing public buildings is a necessary choice to promote energy conservation,emission reduction,and sustainable development goals in the construction industry,and to advance the implementation of the national"carbon peaking and carbon neutrality"strategy.The effective governance of green retrofit projects for existing public buildings essentially involves a dynamic process of repeated strategic interactions among key stakeholders.From the perspective of project governance,this study clarifies the game-theoretic relationship between ESCO and owners under government guidance,and constructs an evolutionary game model involving the government,ESCO,and owners.The study explores the strategic choices of the core stakeholders in the green retrofit projects of existing public buildings.The aim is to lay a foundation for research on the decision-making coordination and implementation mechanisms between ESCO and owners,thus promoting the efficient and healthy development of green retrofit projects for existing public buildings.
