Research On The Seismic Performance Estimation And System Reliability For Reinforced Concrete Structure

Even thought 20 years had been passed from Seimic Resistant Code for Building (GBJ11-89) and 7 years for the new version (GB50011-2001) pressed until Wenchuan earthquake in 2008. A great number of death and enjured and eccnomic losses had been coused for the collapse of building. Most of the destroyed buildings are built after 1989 and the collapse reminds us to examine the now used seismic design method and the constructions. We need to do further research on the area before the new version code press. Normally there will be several different structure schemes with different destroyed type. How to select the more reliable scheme has big value. In this dissertation some problems about structural seismic resistant analysis and reliblity based failure mode selective preference will be considered as follows:1 The calculation formula of energy response and energy spectra for elastic and plastic SDOF system had been evaluated. The influence regulation of earthquake factors and structural factors had been studied. 40 earthquake records had been chosen for each site for energy sepectra calculation and a simplified formula had been presented.2 The mode superstation meth and time history caculation of energy response for the simplified storey MDOF system had been evalued and based on that the hystecric energy destrucbution in storeys had been studied. MSC.MARC had been used to establish accurate FEM model and the energy response had been evaluated. The gross energy response and distribution of plastic deformation of reinforced concrete frame and frame-shear wall structure had been studied. The length of plastic area for one dimension members such as beams or columns and the area of plastic area for two dimension members such as shear walls and slabs had been presented for measure the extent of plastic.3 The limitation of the now used seismic resistant method and seismic performance analysis method had been summaried. According to the hysteric test of beams, columns and shear walls, the limitation of the plastic area of the members had been suggested. And joint together with the damage index of material, a new method that energy based seismic analysis method had been presented. The application on a complex tall building of this method verified its feasibility.4 To simplify the MDOF system to SDOF system and applify the equavelent linear method to calculate the scholastic response of hysteric energy response under stable earthquake excitation and then sovle the dynamic reliability basen on the Markov assumpution. Although it can be used to calculate the dynamic reliability based on the hysteric energy response, it is not a accrate way for its simplification and equivalence.5 The stochastic finite element method is valuble for its accuracy in structural system reliability analysis. Visilization programme GID is used with script language TCL and graphics library TK to develop the stochastic finite element method software Opensees. A module is added to GID is called OSReliablility to analysis structural system reliability and sensitivity of stochastic variables with accrate FEM model. A reliablility analysis method with important schositc variables had been approved.6 Two failure mode"columns stronger than beams"and"beams stronger than columns"for frame structures had been designed and the accurate schositic FEM model which consider the concrete and rebar seprately had been established by OSReiliability. By the system reliability analysis we know that the reliability of"columns stronger than beams"is lager than"beams stronger than columns". Based on which, a method to select a better failure mode with system reliability analysis had been approved.