Nonlinear Static Analysis Of The Reinforced Concrete Frame Structure

Pushover analysis is based on nonlinear static analysis and combines response spectrum to obtain the response of a structure under different levels of earthquake. This method can not only trace the nonlinear deformation of a structure as a result of certain load to get more realistic result than elastic analysis, but also assess the quality of a structure in moderate and severe earthquake according to the response of a structure under different levels of earthquake. The result of such kind of analysis does not vary a lot. Pushover analysis has been quite popular in recent years and been strongly recommended by aseismic design code for buildings of some countries. Thus, it is very important to study and employ this method.The background, evolution (both in China and other countries), problems and latest development of pushover analysis are introduced in this paper. Dynamic load with period,rules of strength change and the relationship between pushover loading level and fortification intensity have been studied through the dynamic time history analysis of the 203 ground motions. Pushover analysis and time history of many R.C.frame structures are conducted making use of SAP2000. Those analyses are concerned with the relationship of the deformation,inter-story drift angle,plastic hinge distribution with different load patterns. The instant characteristics such as period,damping are included in the pushover analysis. It reveals the regularity in the process of elastic, elastic-plastic and structure damage. Therefore, the advantages and disadvantages of different pushover lateral load patterns can be obtained, which improved the study of pushover lateral load patterns. At the last part of this paper, there is a comparison of accuracy of MPA analysis and pushover analysis. When calculating objective displacement of the structure, MPA analysis can include the effect of high mode influence on the displacement. Through the displacement response combination of the high mode, the big error of calculation of the inter-story drift using the original pushover analysis has been improved to certain extent, which is more realistic.