Study On Seismic Performance Of Braced Concrete Frame

The frame-brace structure is an important and effective system which is easy to build and has good performance to resist seismic load.This structure has been used to many buildings widely at home and abroad. Though lots of achievements has been gained in theories and experiments, engineers have not the uniform methods to design buildings.The rules about this system in the codes are very simple which are nowhere near enough.This paper wants to find some methods and suggestion to design building for the engineers.This paper studies on:Firstly,the forms of brace consist of concentrically brace,ecconcentrically brace,buckling-restrained brace and so on.The paper generalizes these forms of braces all aspects of advantages and disadvantages in detials,especially to the buckling-restrained brace which is developed in recent years.Next, the paper use elastic-plastic time history analysis and nonlinear static procedure to compare and optimize the two-dimensional frame-brace models in order to get best anti-seismic capacity with less braces. After compare to lots of models,the paper finds some available and economical methods and suggestions to design the building.More, the paper deduces a reasonable stiffness formula to the multi-story structure.After compare and analysis the paper summerizes the regularities and the reasonable range of the stiffness eigenvalue.Also,the paper find the reasonable range of the number of the braces which is applied to real building design.Finally,a real example is presented.All the conclusions gained in this paper are used to a Mianyang's building which is done great damages in the Wenchuan earthquake.The original design of the Mianyang's building is frame structure.This paper will add some braces to original building.With the comparison to original design,the anti-seismic performance of new structure improves very much. All the conclusions gained in this paper are useful.Results are drawn which can be used as theoretical foundation for further research on the application of the new protocols.