Seismic Disaster Fragility Analysis Of Reinforced Concrete Chimney

As an important kind of towering buildings, the reinforced concrete chimney occupies a very important position in the national industry, the structural safety performance is directly related to the safety of nearby building structure. Under the effect of seismic, the accidents that the reinforced concrete chimney destroyed and collapsed occurred frequently. Once in place, the losses caused by the earthquake is very serious. Therefore, in this paper, a reinforced concrete chimney is taken as the research object. On the basis of probability reliability method, the seismic disaster fragility of the reinforced concrete chimney is analyzed. The main contents of this paper include:(1) The dynamic time history analysis of reinforced concrete chimney. Considering the uncertainties of the structure itself and seismic input, this thesis selects 100 different original seismic waves, establishment of 100 random ground motion-structure samples. Then the nonlinear dynamic time-history analysis of each random sample is proceeded. The regression analysis of obtained data is performed to establish the relationship between structural response and intensity of ground motion.(2) The probability analysis of structural seismic capacities of reinforced concrete chimney. Considering the random characteristics of the structure itself, a Monte Carlo simulation method and probabilistic design module of ANSYS, namely PDS module of the structure’s nonlinear buckling analysis are performed to obtain the loaddisplacement curve, and accordingly define each damage state of the structure. The data is statistically analyzed to get the bearing capacity of mean value and const logarithmic standard deviation under different damage conditions of structure.(3) Seismic disaster fragility analysis of reinforced concrete chimney. Through the results of nonlinear dynamic time history analysis and nonlinear buckling analysis, get the failure probability formula of slight damage state, serious damage state and collapse of the structure. Through the large computation, the seismic disaster fragility curves of the reinforced concrete chimney are drawn out.