Study On Simplified Models And Aseismic Analysis For Mega-structure

Mega structure comes from the development of economy and technique. Because of the huge figure, complexity of the system and obvious classification of the components' force and the components' importance, the analysis of structures turns to be difficult greatly especially for the nonlinear analysis.In this dissertation, firstly, a fine finite model is used to compare the seismic influences to mega structures calculated with the method of SQC and CQC respectivly. Then, some advices are brought forward when mega structures used. Finally, the stiffness and seismic performance in the elastic stage of the mega structures' are analyzed and appraised according to the results calculated.The load-bearing capacity and transmission between different types of components of structural systems could be relatively exactly manifested by fine finite model. But huge workload consumed for nonlinear analysis makes it very difficulty to be used in practice. The principles of the predigestion are explored for this kind of structure system and the simplified methods aiming at the calculating structure is brought forward. Then the rationality and correctness of predigested principle and predigested methods are verified through the comparison to the fine finite model.Based on predigestion model, two types of load methods usually used are selected to analyze the push over of the structures. According to the experimentation results, diversified structure's distortion curves with the same vertex displacement are compared. The validity and practicability of push over analysis in judging of the structures' dynamical performance are researched.Finally, aiming at the domestic circumstance that the study of capacity spectrum is not enough and the method of using it is not uniform, this dissertation select two kinds of capacity spectrum methods usually used, to evaluate structures' seismic performance. Based on the experimentative results, two kinds of capacity spectrum methods are appraised, and the merits and shortages are pointed out. It is worthy to domestic engineers to understand and utilize the capacity spectrum methods.