Seismic Analysis Of Large-span Prestressed Concrete Frame Structure

With the flourishing development of every industry in China recently, the demand of people for large space building becomes higher and higher in industry and daily life, so the application of prestressed concrete long-span structure in engineering will be made more and more widely. In the investigation of all previous earthquake disasters, prestressed concrete structure has been found to have defects of less seismic energy dissipation and worse ductility. As for engineering seismic fortification in China, the main design of prestressed concrete frame structures is still used with two-phase design principle of existing specifications, and present details of seismic design cann’t ensure that it has sufficient ductility to dissipate seismic energy on the struture. Therefore,from the point of view for economic and practical or earthquake fortification, the research on it will be proved to have great practical value.In this paper,structural ductility was evaluated based on the method of combining push-over analysis and the curve of moment-curvature relationship, seismic response of prestressed concrete frame structures under different conditions was analyzed by SAP2000. First,force and deformation characteristics of various stages of structure、 occurrence order and location of plastic hinge as well as capacity spectrum curve (Push-over curve) under different modal were studied wholey,thus the seismic perfo-rmance of overall structure was evaluated. Second, seismic performance of prestressed concrete members were evaluated based on the ductility analysis method through the comparison of prestressed concrete beams with normal ductility of concrete beams.Last, combined with code for concrete seismic design,some design recom men-dations and construction measures were put forward, and some references were provided for future seismic fortification.