Study On Mechanical Properties And Monitoring Analysis Of Long-span Single-curved Double- Layer Suspension Structures

In recent years,suspended-cable structure is popular for its advantages of saving steel,beautiful appearance,reasonable stress and so on.It has been widely used in various exhibitions and gymnasiums.A small number of domestic projects have adopted singlecurved double-layer suspension structure,but the construction technology and monitoring research of this kind of structure are still in its infancy.At present,there is no complete case for the suspension structure monitoring research which integrates construction monitoring and health monitoring,so it is very necessary to conduct in-depth research on this kind of structure.This thesis takes the major key projects of the world's largest suspension structure Exhibition Center(Shijiazhuang International Exhibition Center)as the background.The construction monitoring and health monitoring of the structure are studied in this thesis.Simulation study on the whole construction process of the structure.Solutions to key problems in construction process simulation of suspension structures are proposed.The method of verifying activation and passivation boundary group can simulate temporary support better.Surface elastic support can effectively solve the problem of nonconvergence in suspension structure simulation.Through the simulation analysis of the whole construction process of the structure,the stress of each construction control step and the coordinates of each node are obtained,which can provide control data for the construction site.Research on construction monitoring and health monitoring of structures.In view of the characteristics of the structure type of this project,a set of life cycle joint monitoring system is established,which integrates construction monitoring and health monitoring.The monitoring data of stress,deformation and temperature during construction and service are analyzed and compared with the results of finite element simulation.Verify the reliability and accuracy of the simulation method and construction scheme,judge whether the stress and deformation of the structure in construction process and form meet the requirements,focus on individual members whose tension and compression countersign appears in the formal tension stage of the main cable and whose stress exceeds the construction form,and evaluate the safety condition of the structure during service.The effect of temperature on suspension structure during service is studied.Firstly,the extreme temperature difference analysis considering the closure temperature of the structure is carried out,and the influence ratio of the temperature stress of different members is obtained.Then the stress changes of the structure under different temperature loads are studied,and the correlation between the members and the temperature effect is analyzed.At the same time,the accuracy of the monitoring results is verified.In this thesis,a method is proposed to analyze the influence of extreme temperature difference on the closure temperature of the structure and the temperature effect under multi-temperature loading.The relationship between stress and temperature change and the ratio of temperature stress influence are determined.This thesis solves the key problems and technical problems of construction monitoring and health monitoring of long-span single-curved double-layer suspension structure,in order to provide reference for the research of this type of structure monitoring.