This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade sett...This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade settlement control standard that states that the maximum differential settlement value should be less than 5 cm when the embankment fill height exceeds 20 m.Similarly,the maximum differential settlement value should be less than 10 cm when the embankment fill height does not exceed 20 m.The findings of the study can provide a useful reference for the design of roadbed widening in highway reconstruction and expansion projects.展开更多
China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of diff...China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of different sizes in mountainous areas are unavoidable,and the settlement of high-fill embankments is usually the most concerned issue in high-fill projects.According to the current research of highway projects,most of the high embankments in mountainous areas are soil-rock mixed embankments or rock-filled embankments,and their post-construction settlements are directly related to construction technology and the type of filler used.In this paper,the problems in the settlement control of earth-filled embankment and related factors are analyzed in detail.The settlement control technology of high-fill embankment in high-cold and high-altitude areas is also discussed,so as to ensure the overall quality of high-fill embankment.展开更多
In order to ensure that the tunnel deformation and surface settlement are controlled within the allowable range during the construction process,the design unit has compiled technical measures and monitoring schemes fo...In order to ensure that the tunnel deformation and surface settlement are controlled within the allowable range during the construction process,the design unit has compiled technical measures and monitoring schemes for ground settlement control of this project.Based on the example of a shallow tunneling project on Subway line 8,this paper analyzes and discusses the shallow tunneling method in detail and puts forward corresponding technical measures for ground settlement control.展开更多
The study mainly discusses the issues of the settlement of differences that occurs in the process of highway subgrade widening. Firstly, it briefly introduces the settlement of difference and its harms;then it analyze...The study mainly discusses the issues of the settlement of differences that occurs in the process of highway subgrade widening. Firstly, it briefly introduces the settlement of difference and its harms;then it analyzes the mechanism of settlement of differences in the process of difference widening, including four aspects: the new and old roadbeds themselves, design, construction and other links;finally, based on the above analysis of the mechanism, it discusses the corresponding control measures, mainly proposing these suggestions as followings: the use of lightweight materials, the foundation treatment, the cut slope excavation steps, and the strict control of the degree of compaction, etc. The paper is expected to provide some theoretical basis for the control measures of highway subgrade widening settlement of difference.展开更多
Overall figures of rural settlement landscapes on Guanzhong Plain were summarized,material components of these landscapes were classified into living landscape facilities and production landscape facilities,and then i...Overall figures of rural settlement landscapes on Guanzhong Plain were summarized,material components of these landscapes were classified into living landscape facilities and production landscape facilities,and then introduced respectively.From the perspective of rural central landscapes,rural yard landscapes,rural cluster landscapes and rural road landscapes,evolution of rural landscape spatial forms on Guanzhong Plain was analyzed.Moreover,problems of present rural landscapes were proposed,necessity and urgency of controlling evolution of rural settlement landscapes were stressed,and a rural landscape control mode in view of regional characteristics of Guanzhong Plain was given.展开更多
Increasing Chinese urbanization and industrialization has prompted greater attention to the study of human settlement and the human-land relationship in the fields of geography, architecture, and urban planning. We us...Increasing Chinese urbanization and industrialization has prompted greater attention to the study of human settlement and the human-land relationship in the fields of geography, architecture, and urban planning. We used bibliometric methods and statistical software to review 180 articles on human settlement in 16 Chinese geographical journals. We found that Chinese geographical human settlement research is characterized by the following:(1) Most research focuses on human settlement extension, valuation indicators, models for urban and rural settlements, theoretical exploration and the planning practices of single-factor, human settlement and complex, geographical livability in macro-scale, urban settlement differentiation and ideal patterns in medium scale, the comprehensive evaluation of settlement environment, and the planning of community units in micro-scale, community settlements; socio-cultural investigation and warnings about advancing human settlement.(2) No progress has been made in synthesizing and integrating method systems. PSR models and DPSIR models are used for targeting mechanisms, while the standard settlement evaluation system was composed of physical & economic indicators by questionnaire surveys. On the other hand, spatial clustering based on GIS has been a frequent focus in recent years. Pioneering research on human settlement and theoretical systems within the context of China's urbanization and industrialization will provide guidance on the sustainability of Chinese cities and regions. The following five aspects require greater attention:(1) Natural suitability research on human settlement, and a survey of human settlement demands to reflect the range of different demands concerning ecologically suitable settlements in urban environments, the corresponding valuation indicators, systems, and evolution, and the impact of the residents' socio-economic attributes.(2) Spatial-temporal evaluation and sustainability research on urban and rural human settlement at various scales, focusing on evolution and spatial differen-tiation at various scales such as city clusters and comparisons between cities, within the cities and communities.(3) Development of theory and technology for human settlement evolution research, including detection technology and methods, data mining measures, and forecasting and emulation of regional and urban human settlement evolution processes, mechanisms and patterns.(4) Research on the control of human settlement that focuses on optimization, patterns, and policies for effective management and development.(5) Estimating the human settlement system service value and establishing suitable human settlement systems, including social, economic, cultural and ecological service values.展开更多
深基坑开挖对周边建筑物沉降影响显著,合理的数值模拟方法可为工程设计提供科学依据。论文基于三维有限元方法(Finite Element Method,FEM),建立了包含基坑、支护体系及周边建筑物的数值模型,模拟不同开挖工况及关键因素对沉降的影响。...深基坑开挖对周边建筑物沉降影响显著,合理的数值模拟方法可为工程设计提供科学依据。论文基于三维有限元方法(Finite Element Method,FEM),建立了包含基坑、支护体系及周边建筑物的数值模型,模拟不同开挖工况及关键因素对沉降的影响。研究表明,基坑开挖深度、支护刚度、土层特性及基础形式对建筑物沉降影响显著。浅基础建筑物受基坑开挖影响较大,最大沉降可达30 mm,而桩基础建筑物沉降较小但可能发生桩身侧移。填土地层的沉降量最大,砂土地层表现出显著的差异沉降,而黏土层沉降较均匀但持续时间较长。支护刚度的增加能有效减少地表沉降,但控制效果存在递减趋势。展开更多
文摘This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade settlement control standard that states that the maximum differential settlement value should be less than 5 cm when the embankment fill height exceeds 20 m.Similarly,the maximum differential settlement value should be less than 10 cm when the embankment fill height does not exceed 20 m.The findings of the study can provide a useful reference for the design of roadbed widening in highway reconstruction and expansion projects.
文摘China's infrastructure has gradually achieved large-scale development,and transportation construction has also shifted from east to west,transitioning from plains to mountainous areas.High-fill embankments of different sizes in mountainous areas are unavoidable,and the settlement of high-fill embankments is usually the most concerned issue in high-fill projects.According to the current research of highway projects,most of the high embankments in mountainous areas are soil-rock mixed embankments or rock-filled embankments,and their post-construction settlements are directly related to construction technology and the type of filler used.In this paper,the problems in the settlement control of earth-filled embankment and related factors are analyzed in detail.The settlement control technology of high-fill embankment in high-cold and high-altitude areas is also discussed,so as to ensure the overall quality of high-fill embankment.
文摘In order to ensure that the tunnel deformation and surface settlement are controlled within the allowable range during the construction process,the design unit has compiled technical measures and monitoring schemes for ground settlement control of this project.Based on the example of a shallow tunneling project on Subway line 8,this paper analyzes and discusses the shallow tunneling method in detail and puts forward corresponding technical measures for ground settlement control.
文摘The study mainly discusses the issues of the settlement of differences that occurs in the process of highway subgrade widening. Firstly, it briefly introduces the settlement of difference and its harms;then it analyzes the mechanism of settlement of differences in the process of difference widening, including four aspects: the new and old roadbeds themselves, design, construction and other links;finally, based on the above analysis of the mechanism, it discusses the corresponding control measures, mainly proposing these suggestions as followings: the use of lightweight materials, the foundation treatment, the cut slope excavation steps, and the strict control of the degree of compaction, etc. The paper is expected to provide some theoretical basis for the control measures of highway subgrade widening settlement of difference.
文摘Overall figures of rural settlement landscapes on Guanzhong Plain were summarized,material components of these landscapes were classified into living landscape facilities and production landscape facilities,and then introduced respectively.From the perspective of rural central landscapes,rural yard landscapes,rural cluster landscapes and rural road landscapes,evolution of rural landscape spatial forms on Guanzhong Plain was analyzed.Moreover,problems of present rural landscapes were proposed,necessity and urgency of controlling evolution of rural settlement landscapes were stressed,and a rural landscape control mode in view of regional characteristics of Guanzhong Plain was given.
基金National Natural Science Foundation of China,No.41230632,No.41301110,No.41501119 Zhejiang Provincial Natural Science Foundation of China,No.LY16D010008,No.Y14D010007
文摘Increasing Chinese urbanization and industrialization has prompted greater attention to the study of human settlement and the human-land relationship in the fields of geography, architecture, and urban planning. We used bibliometric methods and statistical software to review 180 articles on human settlement in 16 Chinese geographical journals. We found that Chinese geographical human settlement research is characterized by the following:(1) Most research focuses on human settlement extension, valuation indicators, models for urban and rural settlements, theoretical exploration and the planning practices of single-factor, human settlement and complex, geographical livability in macro-scale, urban settlement differentiation and ideal patterns in medium scale, the comprehensive evaluation of settlement environment, and the planning of community units in micro-scale, community settlements; socio-cultural investigation and warnings about advancing human settlement.(2) No progress has been made in synthesizing and integrating method systems. PSR models and DPSIR models are used for targeting mechanisms, while the standard settlement evaluation system was composed of physical & economic indicators by questionnaire surveys. On the other hand, spatial clustering based on GIS has been a frequent focus in recent years. Pioneering research on human settlement and theoretical systems within the context of China's urbanization and industrialization will provide guidance on the sustainability of Chinese cities and regions. The following five aspects require greater attention:(1) Natural suitability research on human settlement, and a survey of human settlement demands to reflect the range of different demands concerning ecologically suitable settlements in urban environments, the corresponding valuation indicators, systems, and evolution, and the impact of the residents' socio-economic attributes.(2) Spatial-temporal evaluation and sustainability research on urban and rural human settlement at various scales, focusing on evolution and spatial differen-tiation at various scales such as city clusters and comparisons between cities, within the cities and communities.(3) Development of theory and technology for human settlement evolution research, including detection technology and methods, data mining measures, and forecasting and emulation of regional and urban human settlement evolution processes, mechanisms and patterns.(4) Research on the control of human settlement that focuses on optimization, patterns, and policies for effective management and development.(5) Estimating the human settlement system service value and establishing suitable human settlement systems, including social, economic, cultural and ecological service values.
文摘深基坑开挖对周边建筑物沉降影响显著,合理的数值模拟方法可为工程设计提供科学依据。论文基于三维有限元方法(Finite Element Method,FEM),建立了包含基坑、支护体系及周边建筑物的数值模型,模拟不同开挖工况及关键因素对沉降的影响。研究表明,基坑开挖深度、支护刚度、土层特性及基础形式对建筑物沉降影响显著。浅基础建筑物受基坑开挖影响较大,最大沉降可达30 mm,而桩基础建筑物沉降较小但可能发生桩身侧移。填土地层的沉降量最大,砂土地层表现出显著的差异沉降,而黏土层沉降较均匀但持续时间较长。支护刚度的增加能有效减少地表沉降,但控制效果存在递减趋势。