Based on the advantages of the application of Building Information Modelling(BIM)technology in highway engineering,this paper analyzes the difficulties of its in-depth application,grasps the pain points of the applica...Based on the advantages of the application of Building Information Modelling(BIM)technology in highway engineering,this paper analyzes the difficulties of its in-depth application,grasps the pain points of the application of BIM technology in practice,and approaches from the integration of BIM design-construction.This paper also puts forward the integration of cross-stage information based on the BIM+Geographic Information System(GIS)construction information management system to realize the BIM whole life cycle management,and provides directional support for the continuous and efficient application of BIM technology in engineering practice.展开更多
Highway test and detection technology play a very important role in controlling the quality of road and bridge engineering and improving the maintenance of roads and bridges.The study of highway bridge test detection ...Highway test and detection technology play a very important role in controlling the quality of road and bridge engineering and improving the maintenance of roads and bridges.The study of highway bridge test detection technology is both theoretically and practically useful.Road and bridge test and detection is a complicated task.With the development of science and technology,highway and bridge engineering test and detection technology has also made great progress.The continuous improvement of test and detection technology has brought good social benefits to road and bridge construction.This article discusses the problems in test and detection technology of highway bridges and how to improve the quality of test and detection.展开更多
The acceleration of urbanization has promoted the increase in the number of urban highway projects,resulting in an increase of emphasis on the quality of urban highway projects.The quality and safety of highway constr...The acceleration of urbanization has promoted the increase in the number of urban highway projects,resulting in an increase of emphasis on the quality of urban highway projects.The quality and safety of highway construction directly affects the driving comfort,safety,and service life after it is put into operation.Among them,asphalt pavement is an important structure in highway construction,and it is also a key link that directly affects the construction quality.In order to ensure the quality of construction,it is necessary to strengthen on-site testing during the construction process to discover problems in time,and to ensure that the construction is up to standard.This paper mainly presents an analysis on the necessity and application of on-site quality inspection technology for asphalt pavement construction of highway engineering,and outlines measures to improve highway engineering construction testing technology.展开更多
California Bearing Ratio(CBR)test is highly professional and requires a high level of skills.In order to improve the accuracy of the test results,the relevant staff will not only need to understand the rules and proce...California Bearing Ratio(CBR)test is highly professional and requires a high level of skills.In order to improve the accuracy of the test results,the relevant staff will not only need to understand the rules and procedures involved in the test,they would also need to be meticulous in their work to avoid human errors,provide good data support for highway engineering,and improve the overall quality of the project.Therefore,this paper presents an analysis of the application of CBR test in highway engineering,which can provide reference for engineering and promote the development of the highway industry.展开更多
Highway engineering requires higher investment and requires a long time of management compared to other construction projects.There are many factors that affect the project cost during the engineering construction sta...Highway engineering requires higher investment and requires a long time of management compared to other construction projects.There are many factors that affect the project cost during the engineering construction stage of a highway.The effective development of cost management in the construction phase of highway engineering under the list pricing model can avoid unnecessary waste and help control the cost of highway engineering.However,there are still some problems in the development of cost management in the construction phase of highway engineering,which will affect the role of the list-based pricing mode in cost management.This paper explores and analyzes the advantages of the list pricing model and the problems existing in the cost management of the highway engineering construction stage under the list pricing model,and proposes effective management strategies to improve cost management of the highway engineering construction stage.展开更多
This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan for...This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan formulation,mortar shotcrete anchor construction,grid steel frame construction,steel mesh construction,and concrete support construction.This analysis aims to provide a guideline for those interested in applying this technology and improving the quality and safety of highway bridges and tunnels construction.展开更多
It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius fo...It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius for reducing the risk of sand accumulation.In this study,three-dimensional models of desert highway embankments with different vertical curve radii were constructed,and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve embankments.The results show that:(1)Along the direction of the road,the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow,respectively.When the radius of the concave vertical curve is 3000 m,5000 m,8000 m,10000 m and 20000 m,the wind velocity in the middle of the vertical curve is 31.76%,22.58%,10.78%,10.53%and 10.44%,higher than that at both ends.When the radius of the convex vertical curve is 6500 m,8000 m,10000 m,20000 m and 30000 m,the wind velocity at both ends of the vertical curve is 14.06%,9.99%,6.14%,3.22%and 2.41%,higher than that in the middle.The diversion effect also decreases with the increase of the radius.(2)The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1,which is the sediment transport roadbed.The conductivity increases with the increase of radius and gradually tends to be stable.When the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively,the phenomenon of sand accumulation is no longer serious.Under the same radius condition,the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3)Considering the strength of the collection and diversion of the vertical curve embankment with different radii,and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway,the radius of the concave vertical curve is not less than 8000 m,and the radius of the convex vertical curve is not less than 20000 m,which can effectively reduce the sand accumulation of the vertical curve embankment.In the desert highway area,the research results of this paper can provide reference for the design of vertical curve to ensure the safe operation of desert highway.展开更多
Highway project management involves overseeing the on-site construction of a highway project,taking into account the specific circumstances and conditions of the site.This type of management requires a high level of e...Highway project management involves overseeing the on-site construction of a highway project,taking into account the specific circumstances and conditions of the site.This type of management requires a high level of expertise and is characterized by its dynamic and systematic approach.Effective on-site management can ensure the quality,cost-saving,smooth progress,and safety of highway construction.However,there are still some problems in the implementation of site management in some highway projects,which seriously affect the improvement of site management.This paper analyzes the characteristics and existing problems of highway engineering management,and puts forward the effective strategies of site management,hoping that this study will help to improve highway engineering site management.展开更多
The highway engineering process is complex,coupled with a relatively long construction period,hence requires increased coordination between participating units to prevent economic disputes and efficiency losses.The ma...The highway engineering process is complex,coupled with a relatively long construction period,hence requires increased coordination between participating units to prevent economic disputes and efficiency losses.The main body of the construction project needs to strengthen the management and control of funds.In this regard,this paper analyzes the importance of cost management in highway projects by clarifying and analyzing the current cost management status quo problems and causes.The highway engineering cost control strategy and implementation methods are summarized to provide references for improving the quality of highway engineering.展开更多
This paper focuses on the route and roadbed pavement design in highway reconstruction and upgrading projects.It discusses the importance of project design for highway reconstruction and upgrading,highlighting key aspe...This paper focuses on the route and roadbed pavement design in highway reconstruction and upgrading projects.It discusses the importance of project design for highway reconstruction and upgrading,highlighting key aspects of route design and roadbed pavement design.The analysis reveals that the main design considerations in these projects include controlling factors of route reconstruction,expansion,and upgrading,as well as route plan design and longitudinal section design combined with roadbed pavement.In roadbed pavement design,it is crucial for designers to thoroughly collect existing data and make reasonable use of the current roadbed and pavement to develop a comprehensive design scheme.This analysis aims to provide a reference for the reasonable design of such projects.展开更多
In order to systemically summarize and integrate technology of highway construction in permafrost regions on the Qinghai-Tibet Plateau,we studied disciplines and mechanisms of formation and development of problems and...In order to systemically summarize and integrate technology of highway construction in permafrost regions on the Qinghai-Tibet Plateau,we studied disciplines and mechanisms of formation and development of problems and challenges in highway engineer-ing in high-altitude permafrost regions based on construction experiences for 50 years and on 30 years of research regarding the Qinghai-Tibet and Xikang highways.Embankments,pavements,bridges,and countermeasures for ecosystem protection in per-mafrost regions were the main study objects.We combined extensive analysis of key problems of engineering stability with inter-action between permafrost and highways,theoretical models,indoor tests,and field tests to reveal the interaction between em-bankments,pavements,bridge piles,and permafrost.In this paper,we propose a series of engineering measures for highway sta-bility,design parameters,key indexes for pavement durability in low temperature,relationships between re-freezing time of bridge-pile foundation and strength development as well as ecosystem recovery in high-latitude cold regions;these eventually form a construction technology package for permafrost regions.展开更多
Highway engineering construction plays a pivotal role in driving urban economic development,in the face of modern urban transportation high-quality development.To achieve high-quality development in modern urban trans...Highway engineering construction plays a pivotal role in driving urban economic development,in the face of modern urban transportation high-quality development.To achieve high-quality development in modern urban transportation,it is imperative to engage in effective management practices.This article analyzes the technology involved in highway engineering construction,delving into key aspects of highway construction technology,and examining measures for managing and controlling highway engineering construction technology effectively.展开更多
In recent years,the scale of China’s highway projects have been expanding.However,in real life,road construction projects in some places have not passed professional and rigorous inspections,resulting in various qual...In recent years,the scale of China’s highway projects have been expanding.However,in real life,road construction projects in some places have not passed professional and rigorous inspections,resulting in various quality problems,and seriously affecting the safety of drivers and pedestrians.This paper analyzes the current situation of highway engineering test and detection,expounds the application of new technologies for highway engineering test and detection.In this paper,a case study was carried out on ground penetrating radar(GPR),which aims to improve highway engineering test and detection and provide reference for reducing highway safety risks.展开更多
Due to a series of linear projects built along National Highway 214,the second"Permafrost Engineering Corridor"on the Qinghai-Tibet Plateau has formed.In this paper,by overcoming the problems of data decentr...Due to a series of linear projects built along National Highway 214,the second"Permafrost Engineering Corridor"on the Qinghai-Tibet Plateau has formed.In this paper,by overcoming the problems of data decentralization and standard inconsistency,permafrost characteristics and changes along the engineering corridor are systematically summarized based on the survey and monitoring data.The results show that:1)Being controlled by elevation,the permafrost is distributed in flake discontinuity with mountains as the center along the line.The total length of the road section in permafrost regions is 365 km,of which the total length of the permafrost section of National Highway 214 is 216.7 km,and the total length of the permafrost section of Gong-Yu Expressway is 197.3 km.The mean annual ground temperature(MAGT)is higher than−1.5℃,and permafrost with MAGT lower than−1.5℃ is only distributed in the sections at Bayan Har Mountain and E'la Mountain.There are obvious differences in the distribution of ground ice in the different sections along the engineering corridor.The sections with high ice content are mainly located in Zuimatan,Duogerong Plain and the top of north and south slope of Bayan Har Mountain.The permafrost thickness is controlled by the ground temperature,and permafrost thickness increases with the decrease of the ground temperature,with the change rate of about 37 m/℃.2)Local factors(topography,landform,vegetation and lithology)affect the degradation process of permafrost,and then affect the distribution,ground temperature,thickness and ice content of permafrost.Asphalt pavement has greatly changed the heat exchange balance of the original ground,resulting in serious degradation of the permafrost.Due to the influence of roadbed direction trend,the phenomenon of shady-sunny slope is very significant in most sections along the line.The warming range of permafrost under the roadbed is gradually smaller with the increase of depth,so the thawing settlement of the shallow section with high ice-content permafrost is more significant.展开更多
In the maintenance work of highway and bridge engineering structures,the fracture delay of high-strength bolts is a content that needs to be focused on and researched.Based on this,the paper analyzes the fracture dela...In the maintenance work of highway and bridge engineering structures,the fracture delay of high-strength bolts is a content that needs to be focused on and researched.Based on this,the paper analyzes the fracture delay of high-strength bolts in highway bridge maintenance,including an overview of the fundamental research on fracture delay and related specific studies.It is hoped that this study can provide scientific reference for the reasonable maintenance of high-strength bolts,so as to ensure the overall maintenance effect of highway bridge projects.展开更多
PLANNED in 2003,construction of the 1,092-meter-long ShanghaiNantong Railway Yangtze River Bridge–the world’s longest rail-cumroad cable-stayed steel bridge–started in 2014.On completion in 2019,it will span the 13...PLANNED in 2003,construction of the 1,092-meter-long ShanghaiNantong Railway Yangtze River Bridge–the world’s longest rail-cumroad cable-stayed steel bridge–started in 2014.On completion in 2019,it will span the 130 km.between the two cities,shortening to one hour the drive from Shanghai to Nantong.展开更多
The four-level Serbian highway engineering standards system composed of national standards,international standards,laws/bylaws and regulations,organized and operated by Institute for Standardization of Serbia(ISS)and ...The four-level Serbian highway engineering standards system composed of national standards,international standards,laws/bylaws and regulations,organized and operated by Institute for Standardization of Serbia(ISS)and Ministry of Construction,Transport and Infrastructure(MCTI),are introduced,including its history,management system and the focus of Serbian standards.It’s expected to be helpful for related technical staff.展开更多
In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting stre...In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting strength, stability and water stability test;the design of the experiment involved changing gyration number, emulsified asphalt and water content, molded specimen temperature and other factors to analyze the volume parameters, mechanical properties and water stability. The results show that both the maximum dry density and dry and wet splitting strength ratio(DWSSR) of emulsified asphalt cold reclaimed mixture are improved by the rotary compacting method, while the porosity and the optimal dosage of water are reduced. Furthermore, with the increase of compaction times, the porosity and splitting strength index both change exponentially. DWSSR and porosity are consistent with quadratic functions. The use of gyratory compaction for 70 times at 25 °C and the optimum dosage of emulsified asphalt can be determined based on the splitting strength ratio. The high-temperature stability and water damage resistance of the pavement can be improved by the use of rotary compacting method effectively, and the early strength and road performance are higher than the regulatory requirements.展开更多
Two different reinforcing methodologies are applied:modification of the overlay characteristics by adding chopped glass fibers to the hot mixture asphalt (HMA) and reinforcing asphalt overlay with glass grids.Theor...Two different reinforcing methodologies are applied:modification of the overlay characteristics by adding chopped glass fibers to the hot mixture asphalt (HMA) and reinforcing asphalt overlay with glass grids.Theory of fracture mechanics (FM) is employed to determine crack growth rates for the suggested anti-cracking overlay systems.Asphalt mixture designing tests,three point bending tests and fatigue crack propagation tests were carried out.The critical stress intensity factors KIC are determined for plain and reinforced asphalt concrete.Depending on the fatigue crack propagation,the crack growth rate is determined for each type of anti-cracking system and the cracking process is also analyzed.One of the significant points in this study is the attempt to give better understanding of the crack propagation for multilayer asphaltic overlay or what are suggested herein to be called composite structure anti-cracking overlay system.The results indicate that the reinforcing materials improve anti-cracking characteristics of the asphalt concrete.Composite structure anti-cracking overlay gives a good solution for the reflective cracking phenomenon over old cracked pavements.展开更多
Proper treatment of weak subgrade soil is very important to building a highway of good quality. We proposed an entropy-based multi-criterion group decision analysis method for a group of experts to evaluate alternativ...Proper treatment of weak subgrade soil is very important to building a highway of good quality. We proposed an entropy-based multi-criterion group decision analysis method for a group of experts to evaluate alternatives of weak subgrade treatment, with an aim to select the optimum technique which is technically, economically and socially viable. We used fuzzy theory to analyze multiple experts' evaluation on various factors of each alterative treatment. Different experts' evaluations are integrated by the group eigenvalue method. An entropy weight is introduced to minimize the negative influences of subjective human factors of experts. The optimum alternative is identified with ideal point diseriminant analysis to calculate the distance of each alternative to the ideal point and prioritize all alternatives according to their distances. A case study on a section of the Shiman Expressway verified that the proposed method can give a rational decision on the optimum method of weak subgrade treatment.展开更多
基金Chongqing Engineering Institute 2023 Intramural Research Fund Grant Project:Highway Engineering Construction Process Management and Technological Innovation Research Based on BIM Technology(Project number:2023xzky04)。
文摘Based on the advantages of the application of Building Information Modelling(BIM)technology in highway engineering,this paper analyzes the difficulties of its in-depth application,grasps the pain points of the application of BIM technology in practice,and approaches from the integration of BIM design-construction.This paper also puts forward the integration of cross-stage information based on the BIM+Geographic Information System(GIS)construction information management system to realize the BIM whole life cycle management,and provides directional support for the continuous and efficient application of BIM technology in engineering practice.
文摘Highway test and detection technology play a very important role in controlling the quality of road and bridge engineering and improving the maintenance of roads and bridges.The study of highway bridge test detection technology is both theoretically and practically useful.Road and bridge test and detection is a complicated task.With the development of science and technology,highway and bridge engineering test and detection technology has also made great progress.The continuous improvement of test and detection technology has brought good social benefits to road and bridge construction.This article discusses the problems in test and detection technology of highway bridges and how to improve the quality of test and detection.
文摘The acceleration of urbanization has promoted the increase in the number of urban highway projects,resulting in an increase of emphasis on the quality of urban highway projects.The quality and safety of highway construction directly affects the driving comfort,safety,and service life after it is put into operation.Among them,asphalt pavement is an important structure in highway construction,and it is also a key link that directly affects the construction quality.In order to ensure the quality of construction,it is necessary to strengthen on-site testing during the construction process to discover problems in time,and to ensure that the construction is up to standard.This paper mainly presents an analysis on the necessity and application of on-site quality inspection technology for asphalt pavement construction of highway engineering,and outlines measures to improve highway engineering construction testing technology.
文摘California Bearing Ratio(CBR)test is highly professional and requires a high level of skills.In order to improve the accuracy of the test results,the relevant staff will not only need to understand the rules and procedures involved in the test,they would also need to be meticulous in their work to avoid human errors,provide good data support for highway engineering,and improve the overall quality of the project.Therefore,this paper presents an analysis of the application of CBR test in highway engineering,which can provide reference for engineering and promote the development of the highway industry.
文摘Highway engineering requires higher investment and requires a long time of management compared to other construction projects.There are many factors that affect the project cost during the engineering construction stage of a highway.The effective development of cost management in the construction phase of highway engineering under the list pricing model can avoid unnecessary waste and help control the cost of highway engineering.However,there are still some problems in the development of cost management in the construction phase of highway engineering,which will affect the role of the list-based pricing mode in cost management.This paper explores and analyzes the advantages of the list pricing model and the problems existing in the cost management of the highway engineering construction stage under the list pricing model,and proposes effective management strategies to improve cost management of the highway engineering construction stage.
文摘This article analyzes the application strategies of shotcrete anchor support technology using a highway bridge-tunnel construction project as an example.The article covers various strategies,including support plan formulation,mortar shotcrete anchor construction,grid steel frame construction,steel mesh construction,and concrete support construction.This analysis aims to provide a guideline for those interested in applying this technology and improving the quality and safety of highway bridges and tunnels construction.
基金The research described in this paper was financially supported by Youth Science Foundation Project’Research on Failure Mechanism and Evaluation Method of Sand Control Measures for Railway Machinery in Sandy Area’(12302511)Ningxia Transportation Department Science and Technology Project(20200173)Central guide local science and technology development funds(22ZY1QA005)。
文摘It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius for reducing the risk of sand accumulation.In this study,three-dimensional models of desert highway embankments with different vertical curve radii were constructed,and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve embankments.The results show that:(1)Along the direction of the road,the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow,respectively.When the radius of the concave vertical curve is 3000 m,5000 m,8000 m,10000 m and 20000 m,the wind velocity in the middle of the vertical curve is 31.76%,22.58%,10.78%,10.53%and 10.44%,higher than that at both ends.When the radius of the convex vertical curve is 6500 m,8000 m,10000 m,20000 m and 30000 m,the wind velocity at both ends of the vertical curve is 14.06%,9.99%,6.14%,3.22%and 2.41%,higher than that in the middle.The diversion effect also decreases with the increase of the radius.(2)The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1,which is the sediment transport roadbed.The conductivity increases with the increase of radius and gradually tends to be stable.When the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively,the phenomenon of sand accumulation is no longer serious.Under the same radius condition,the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3)Considering the strength of the collection and diversion of the vertical curve embankment with different radii,and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway,the radius of the concave vertical curve is not less than 8000 m,and the radius of the convex vertical curve is not less than 20000 m,which can effectively reduce the sand accumulation of the vertical curve embankment.In the desert highway area,the research results of this paper can provide reference for the design of vertical curve to ensure the safe operation of desert highway.
文摘Highway project management involves overseeing the on-site construction of a highway project,taking into account the specific circumstances and conditions of the site.This type of management requires a high level of expertise and is characterized by its dynamic and systematic approach.Effective on-site management can ensure the quality,cost-saving,smooth progress,and safety of highway construction.However,there are still some problems in the implementation of site management in some highway projects,which seriously affect the improvement of site management.This paper analyzes the characteristics and existing problems of highway engineering management,and puts forward the effective strategies of site management,hoping that this study will help to improve highway engineering site management.
文摘The highway engineering process is complex,coupled with a relatively long construction period,hence requires increased coordination between participating units to prevent economic disputes and efficiency losses.The main body of the construction project needs to strengthen the management and control of funds.In this regard,this paper analyzes the importance of cost management in highway projects by clarifying and analyzing the current cost management status quo problems and causes.The highway engineering cost control strategy and implementation methods are summarized to provide references for improving the quality of highway engineering.
文摘This paper focuses on the route and roadbed pavement design in highway reconstruction and upgrading projects.It discusses the importance of project design for highway reconstruction and upgrading,highlighting key aspects of route design and roadbed pavement design.The analysis reveals that the main design considerations in these projects include controlling factors of route reconstruction,expansion,and upgrading,as well as route plan design and longitudinal section design combined with roadbed pavement.In roadbed pavement design,it is crucial for designers to thoroughly collect existing data and make reasonable use of the current roadbed and pavement to develop a comprehensive design scheme.This analysis aims to provide a reference for the reasonable design of such projects.
文摘In order to systemically summarize and integrate technology of highway construction in permafrost regions on the Qinghai-Tibet Plateau,we studied disciplines and mechanisms of formation and development of problems and challenges in highway engineer-ing in high-altitude permafrost regions based on construction experiences for 50 years and on 30 years of research regarding the Qinghai-Tibet and Xikang highways.Embankments,pavements,bridges,and countermeasures for ecosystem protection in per-mafrost regions were the main study objects.We combined extensive analysis of key problems of engineering stability with inter-action between permafrost and highways,theoretical models,indoor tests,and field tests to reveal the interaction between em-bankments,pavements,bridge piles,and permafrost.In this paper,we propose a series of engineering measures for highway sta-bility,design parameters,key indexes for pavement durability in low temperature,relationships between re-freezing time of bridge-pile foundation and strength development as well as ecosystem recovery in high-latitude cold regions;these eventually form a construction technology package for permafrost regions.
文摘Highway engineering construction plays a pivotal role in driving urban economic development,in the face of modern urban transportation high-quality development.To achieve high-quality development in modern urban transportation,it is imperative to engage in effective management practices.This article analyzes the technology involved in highway engineering construction,delving into key aspects of highway construction technology,and examining measures for managing and controlling highway engineering construction technology effectively.
文摘In recent years,the scale of China’s highway projects have been expanding.However,in real life,road construction projects in some places have not passed professional and rigorous inspections,resulting in various quality problems,and seriously affecting the safety of drivers and pedestrians.This paper analyzes the current situation of highway engineering test and detection,expounds the application of new technologies for highway engineering test and detection.In this paper,a case study was carried out on ground penetrating radar(GPR),which aims to improve highway engineering test and detection and provide reference for reducing highway safety risks.
基金This research was supported by the National Natural Science Foundation of China(Grant No.41971093).
文摘Due to a series of linear projects built along National Highway 214,the second"Permafrost Engineering Corridor"on the Qinghai-Tibet Plateau has formed.In this paper,by overcoming the problems of data decentralization and standard inconsistency,permafrost characteristics and changes along the engineering corridor are systematically summarized based on the survey and monitoring data.The results show that:1)Being controlled by elevation,the permafrost is distributed in flake discontinuity with mountains as the center along the line.The total length of the road section in permafrost regions is 365 km,of which the total length of the permafrost section of National Highway 214 is 216.7 km,and the total length of the permafrost section of Gong-Yu Expressway is 197.3 km.The mean annual ground temperature(MAGT)is higher than−1.5℃,and permafrost with MAGT lower than−1.5℃ is only distributed in the sections at Bayan Har Mountain and E'la Mountain.There are obvious differences in the distribution of ground ice in the different sections along the engineering corridor.The sections with high ice content are mainly located in Zuimatan,Duogerong Plain and the top of north and south slope of Bayan Har Mountain.The permafrost thickness is controlled by the ground temperature,and permafrost thickness increases with the decrease of the ground temperature,with the change rate of about 37 m/℃.2)Local factors(topography,landform,vegetation and lithology)affect the degradation process of permafrost,and then affect the distribution,ground temperature,thickness and ice content of permafrost.Asphalt pavement has greatly changed the heat exchange balance of the original ground,resulting in serious degradation of the permafrost.Due to the influence of roadbed direction trend,the phenomenon of shady-sunny slope is very significant in most sections along the line.The warming range of permafrost under the roadbed is gradually smaller with the increase of depth,so the thawing settlement of the shallow section with high ice-content permafrost is more significant.
文摘In the maintenance work of highway and bridge engineering structures,the fracture delay of high-strength bolts is a content that needs to be focused on and researched.Based on this,the paper analyzes the fracture delay of high-strength bolts in highway bridge maintenance,including an overview of the fundamental research on fracture delay and related specific studies.It is hoped that this study can provide scientific reference for the reasonable maintenance of high-strength bolts,so as to ensure the overall maintenance effect of highway bridge projects.
文摘PLANNED in 2003,construction of the 1,092-meter-long ShanghaiNantong Railway Yangtze River Bridge–the world’s longest rail-cumroad cable-stayed steel bridge–started in 2014.On completion in 2019,it will span the 130 km.between the two cities,shortening to one hour the drive from Shanghai to Nantong.
基金Basic Research on Standardization of Engineering Construction (2023),Standard Quota Research Institute of the Ministry of Housing and Urban Rural Development
文摘The four-level Serbian highway engineering standards system composed of national standards,international standards,laws/bylaws and regulations,organized and operated by Institute for Standardization of Serbia(ISS)and Ministry of Construction,Transport and Infrastructure(MCTI),are introduced,including its history,management system and the focus of Serbian standards.It’s expected to be helpful for related technical staff.
基金Projects(51708048,51704040)supported by the National Natural Science Foundation of ChinaProject(17C0050)supported by the Scientific Research Project of Hunan Provincial Department of Education for General Scholars,China+1 种基金Project(kfj160103)supported by the Open Fund of State Engineering Laboratory of Highway Maintenance Technology(Changsha University of Science&Technology),ChinaProject supported by the Open Fund of Guangxi Key Lab of Road Structure and Materials,China
文摘In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting strength, stability and water stability test;the design of the experiment involved changing gyration number, emulsified asphalt and water content, molded specimen temperature and other factors to analyze the volume parameters, mechanical properties and water stability. The results show that both the maximum dry density and dry and wet splitting strength ratio(DWSSR) of emulsified asphalt cold reclaimed mixture are improved by the rotary compacting method, while the porosity and the optimal dosage of water are reduced. Furthermore, with the increase of compaction times, the porosity and splitting strength index both change exponentially. DWSSR and porosity are consistent with quadratic functions. The use of gyratory compaction for 70 times at 25 °C and the optimum dosage of emulsified asphalt can be determined based on the splitting strength ratio. The high-temperature stability and water damage resistance of the pavement can be improved by the use of rotary compacting method effectively, and the early strength and road performance are higher than the regulatory requirements.
文摘Two different reinforcing methodologies are applied:modification of the overlay characteristics by adding chopped glass fibers to the hot mixture asphalt (HMA) and reinforcing asphalt overlay with glass grids.Theory of fracture mechanics (FM) is employed to determine crack growth rates for the suggested anti-cracking overlay systems.Asphalt mixture designing tests,three point bending tests and fatigue crack propagation tests were carried out.The critical stress intensity factors KIC are determined for plain and reinforced asphalt concrete.Depending on the fatigue crack propagation,the crack growth rate is determined for each type of anti-cracking system and the cracking process is also analyzed.One of the significant points in this study is the attempt to give better understanding of the crack propagation for multilayer asphaltic overlay or what are suggested herein to be called composite structure anti-cracking overlay system.The results indicate that the reinforcing materials improve anti-cracking characteristics of the asphalt concrete.Composite structure anti-cracking overlay gives a good solution for the reflective cracking phenomenon over old cracked pavements.
基金the National Natural Science Foundation of China (No.50478090)the Key Plan of Science and Technology of Hubei Provincial Communication Department (No.2005jtkj361)
文摘Proper treatment of weak subgrade soil is very important to building a highway of good quality. We proposed an entropy-based multi-criterion group decision analysis method for a group of experts to evaluate alternatives of weak subgrade treatment, with an aim to select the optimum technique which is technically, economically and socially viable. We used fuzzy theory to analyze multiple experts' evaluation on various factors of each alterative treatment. Different experts' evaluations are integrated by the group eigenvalue method. An entropy weight is introduced to minimize the negative influences of subjective human factors of experts. The optimum alternative is identified with ideal point diseriminant analysis to calculate the distance of each alternative to the ideal point and prioritize all alternatives according to their distances. A case study on a section of the Shiman Expressway verified that the proposed method can give a rational decision on the optimum method of weak subgrade treatment.