Prestressed System Analysis And Study On Seismic Behavior Of Large Cantilevered Steel Roof Structure

Prestressed steel structure is popular with the construction industry at home and abroad in the past 20 years. Large-scale prestressed steel project built in China have been nearly a hundred in recent years, the size of its engineering and technical levels have reached the international advanced level. However, due to the comparatively short developed time, the study on seismic behavior is less and not deep enough. Large cantilevered structure is widely used in the stadium projects, external prestressed system that is the prestressed cable are disposed outside structure bodies is popular with the spatial hybrid structure. Cable-Stayed, Suspension Cables, Beam String are used in most system of externally prestressed steel project, external prestressed system that is the prestressed cable are disposed in the surface of roof is seldom used in large cantilevered structure. The large cantilevered structural project request high theoretical research and system innovation, and is difficult to construct. The project includes a certain number of prestressed cable and tension bar. Such prestressed component is very important to the structural safety. But the study of the status of such elements in the rarely earthquake also did not draw enough attention. It is essential to do in-depth comprehensive study on seismic performance of the prestressed component to the structure. This paper will take the model of the A stadium in Guiyang as the research object. The researches include prestressed system analysis, modal character analysis, common work of the under concrete support and the steel roof structure, earthquake response spectrum and time history analysis, elastic-plastic analysis under severe earthquake, specific studies include:To analyze prestressed system of the structure, come to a conclusion that the impact of prestressed system on structural stiffness and mechanical behavior. Do structural properties of stiffness and stress analysis on the different parameters and make an evaluation of the impact of various parameters on structural stiffness and mechanical behavior.Make a dynamic performance analysis of the structure, sum up the impact of prestressed system on structural modal; do seismic analysis of the structure under light earthquake. Use response spectrum analysis to study the performance of the structure component. Compare the seismic response of horizontal and vertical dimension to indicate the difference. Establish the whole model of the stadium include the steel roof structure and the under concrete structure to study the common work between them. Do analysis on static, dynamic interaction of the two to compare the difference of the models.Use time history analysis to study the performance of the structure component under light earthquake, compare the seismic response of the two methods to indicate the difference, give a reasonable advice about the methods of seismic analysis. Consider geometry and nonlinear material nonlinearity to do multi-dimensional seismic analysis of the structure under severe earthquake, give safety performance assessment of this structure under severe earthquake.In this paper, we did detailed analysis of the stadium, reveals the static and dynamic performance of the structure, achieved the corresponding conclusions, and the research results directly applied to the projects.