Seismic Fragility And Risk Analysis Of RC Buildings

With Indian plate moved to north continuously and squeezed Asian plate, Wenchuan earthquake was happened in May,12,2008, at the same time many thousands people's life were been taken away and the whole West China economy also been destroyed deeply. Now people are still anxious that high risk of the same large earthquake in the region of West China is not decreased after two years. So how to evaluate reliability and vulnerability of the lifeline systems for future earthquake in the area and search reasonable design practice of seismic strengthening of these buildings is urgent mission.Vulnerability assessment of buildings act important role when a region injured by earthquake, but the job is generally been carried out post earthquake, How to put out vulnerability assessment before natural disaster occurred and even avoid huge loss is another thinking about earthquake. and this is seismic fragility and disaster risk analysis.Earthquake loss evaluation model (ELEM) of a given region be created is not only forecast influence about economy and society post natural disaster but also reduce seismic risk, we can make up lifeline systems based the ELEM and moreover result of seismic vulnerability can guide whether to be worth in carried out seismic strengthening such an based-isolated technology for the injured buildings.The seismic vulnerability research is actual important part of perform based seismic design (PBSD), and the research work is inevitably lasting along perform based seismic design theory.The representative response spectrum of West China is been built and fit unsteady initial stochastic record in consideration of characteristic of frequency and random angle of phase position. The actual applied stochastic wave is be created after initial wave optimized with code spectrum.System conclusion about vulnerability parameter through two kind of classical sample RC buildings dynamic inelastic analysis, the result in contrast of others vulnerability index revealed that proposed vulnerability index (PPI) in article is absolutely response fragility level of buildings.Buildings catalogue also been compared between China code and HAZUS2003 from Federal Emergency Management Agency (FEMA), at the same time list physical describe of damage level and limit states overseas research, the article titled damage level catalogue table and limit states to aim at West China on the basis of the result.The representative four, six and eight storey RC building on the basis of a lot of survey in region of West and Central China are been selected, and assuming material character and part of load abbey of normal distribution in premise,90 stochastic records compatible with the response spectrum of China seismic code and several famous earthquake records also been selected to represent the variability in ground motion. So forming 1350 frame system-earthquake records, Increment dynamic analysis and dynamic history analysis are been used separately and seismic performance and inelastic damage deformation have been found out, analytical vulnerability curve have been also obtained including not only original buildings but also seismic strengthening buildings.The representative RC-shear wall buildings and industrial buildings are been selected and seismic vulnerability analysis been made based dynamic history method, the analytical vulnerability curves are been obtained firstly in homeland.The seismic performance and vulnerability of strengthen old structures with mild steel diagonal bracing damper and mid-story seismic isolation and reduction were also been analysed, seismic capacity and vulnerability of after strength and original building were been compared.Discussion of earthquake insurance of homeland is going on and contrasting with overseas, the specific ratio of earthquake insurance is been taken the lead in accordance with computed analytical vulnerability curves in homeland, the value of the loss based theoretical vulnerability analysis and actual site survey post Wenchuan earthquake were been compared and result is fitted very well each other and demonstrated computed analytical vulnerability curve of classical buildings in West China is correct and have significant theoretical guidance.