This study aims to reveal the macroscopic permanent deformation(PD)behavior and the internal structural evolution of construction and demolition waste(CDW)under loading.Firstly,the initial matric suction of CDW was me...This study aims to reveal the macroscopic permanent deformation(PD)behavior and the internal structural evolution of construction and demolition waste(CDW)under loading.Firstly,the initial matric suction of CDW was measured by the filter paper method.Secondly,the PD of CDW with different humidity and stress states was investigated by repeated load triaxial tests,and a comprehensive prediction model was established.Finally,the discrete element method was performed to analyze the internal structural evolution of CDW during deformation.These results showed that the VAN-GENUCHTEN model could describe the soil-water characteristic curve of CDW well.The PD increases with the increase of the deviator stress and the number of cyclic loading,but the opposite trend was observed when the initial matric suction and confining pressure increased.The proposed model in this study provides a satisfactory prediction of PD.The discrete element method could accurately simulate the macroscopic PD of CDW,and the shear force,interlock force and sliding content increase with the increase of deviator stress during the deformation.The research could provide useful reference for the deformation stability analysis of CDW under cyclic loading.展开更多
During the desing of channel transect,the paper brings forward golden section method,which is 0.618 methods.In order to reduce the calculation volume of the natural depth of water h 0 and bottomˉwidth b which apply ...During the desing of channel transect,the paper brings forward golden section method,which is 0.618 methods.In order to reduce the calculation volume of the natural depth of water h 0 and bottomˉwidth b which apply trial calculation method and graphic method,and improve the calculate precision,the mathematical model has been built up,the writer combines example to explain the train of thought,the result shows that the calculation precision is high,the correctness is tested and verified by the result which is calculated by hand.It can be referred to the hydroelectric works.展开更多
为了提高建筑施工安全风险管理的信息化水平,以建筑施工活动及事故风险类型为研究对象,建立施工安全知识图谱。通过知识图谱改进作业条件危险性评价法(LEC)实现安全风险的定量计算,并基于知识图谱进行风险位置识别和不安全因素分析。研...为了提高建筑施工安全风险管理的信息化水平,以建筑施工活动及事故风险类型为研究对象,建立施工安全知识图谱。通过知识图谱改进作业条件危险性评价法(LEC)实现安全风险的定量计算,并基于知识图谱进行风险位置识别和不安全因素分析。研究提出安全风险虚体实化理念,实现了安全风险信息在数字空间实体化表达;基于建筑信息模型(Building Information Modeling, BIM)和知识图谱技术,建立了建筑施工安全风险信息模型(Building Construction Safety Risk Information Model, BCSRIM)。该模型有效避免了传统LEC法中主观因素产生的影响,实现了建筑施工安全风险定量计算、风险位置识别、风险分析及可视化管理。利用Revit二次开发技术,在Microsoft Visual Studio中使用C#语言连接Neo4j图数据库,完成了基于知识图谱的BCSRIM的开发。试验显示,研究提出的BCSRIM对提高施工现场的管理水平具有较高的实用价值。展开更多
基金Project(52025085)supported by the National Science Fund for Distinguished Young Scholars,ChinaProjects(51927814,51878078)supported by the National Natural Science Foundation of China+3 种基金Project(2018-025)supported by the Training Program for High-level Technical Personnel in Transportation Industry,ChinaProject(CTKY-PTRC 2018-003)supported by the Design Theory,Method and Demonstration of Durability Asphalt Pavement Based on Heavy-duty Traffic Conditions in Shanghai Area,ChinaProject(2020RC4048)supported by the Science and Technology Innovation Program of Hunan Province,ChinaProject(SJCX202001)supported by the Construction Project for Graduate Students of Changsha University of Science&Technology,China。
文摘This study aims to reveal the macroscopic permanent deformation(PD)behavior and the internal structural evolution of construction and demolition waste(CDW)under loading.Firstly,the initial matric suction of CDW was measured by the filter paper method.Secondly,the PD of CDW with different humidity and stress states was investigated by repeated load triaxial tests,and a comprehensive prediction model was established.Finally,the discrete element method was performed to analyze the internal structural evolution of CDW during deformation.These results showed that the VAN-GENUCHTEN model could describe the soil-water characteristic curve of CDW well.The PD increases with the increase of the deviator stress and the number of cyclic loading,but the opposite trend was observed when the initial matric suction and confining pressure increased.The proposed model in this study provides a satisfactory prediction of PD.The discrete element method could accurately simulate the macroscopic PD of CDW,and the shear force,interlock force and sliding content increase with the increase of deviator stress during the deformation.The research could provide useful reference for the deformation stability analysis of CDW under cyclic loading.
文摘During the desing of channel transect,the paper brings forward golden section method,which is 0.618 methods.In order to reduce the calculation volume of the natural depth of water h 0 and bottomˉwidth b which apply trial calculation method and graphic method,and improve the calculate precision,the mathematical model has been built up,the writer combines example to explain the train of thought,the result shows that the calculation precision is high,the correctness is tested and verified by the result which is calculated by hand.It can be referred to the hydroelectric works.
文摘为了提高建筑施工安全风险管理的信息化水平,以建筑施工活动及事故风险类型为研究对象,建立施工安全知识图谱。通过知识图谱改进作业条件危险性评价法(LEC)实现安全风险的定量计算,并基于知识图谱进行风险位置识别和不安全因素分析。研究提出安全风险虚体实化理念,实现了安全风险信息在数字空间实体化表达;基于建筑信息模型(Building Information Modeling, BIM)和知识图谱技术,建立了建筑施工安全风险信息模型(Building Construction Safety Risk Information Model, BCSRIM)。该模型有效避免了传统LEC法中主观因素产生的影响,实现了建筑施工安全风险定量计算、风险位置识别、风险分析及可视化管理。利用Revit二次开发技术,在Microsoft Visual Studio中使用C#语言连接Neo4j图数据库,完成了基于知识图谱的BCSRIM的开发。试验显示,研究提出的BCSRIM对提高施工现场的管理水平具有较高的实用价值。
