Application Of Performance-Based Seismic Reinforcement In Frame Structures

The performance based seismic design theory is a new concept in the civil engineering field since 1990's. Aiming at improving the target performance level of strctures, the theory requires that the performance of structures desingned using it should be predictable. In china, the study on it is in its first stage, and lots of buildings in our city are in old age, so the theory is of pratical value to the structure design of reinforcement.This paper reviews performance-based design thought, and introduces some design methods based on performance, then discusses that how to divide reinforcement-concrect frame structures seismic resistance performance goals and the adoption of interlayer shift angle beam-column plastic hinge rotating quantity as the quantitative indexes of performance-based seismic resistance design.Capacity spectrum method is one of the simplified evaluation methods based on performance design. Its essence is evaluating the response property of structures on decided earthquake action by superposed earthquake response spectrum curves and structure capacity spectrum curve. This paper discuss the basic principles and implementation procedure of the method systemically, and evaluate a practical frame structures seismic resistance performance with finite element software SAP2000.Because of inhere structure dissatisfying the quantitative indexes, we reinforce the structure with two reinforce methods, then compare the influence to the result at two different methods, finally obtain corresponding conclusions. Capacity curves is able to reflect the structure resistance capacity under horizontal force, especially, judgment of plastic hinge positions is s important. We also can comprehend structure mechanical characteristic of different parts and failure paths by push-over analyze. Obviously, we need further analyze to the performance level of reinforced structures.