Time-varying seismic vulnerability analysis of RC frame structures in offshore atmospheric environment
The chloride ions in the offshore atmospheric environment will erode the RC frame structure,resulting in the continuous deterioration of material properties,which ultimately reduces the seismic performance of the RC frame structure.In order to study the change rule of seismic damage risk of RC frame structure under offshore atmospheric environment,this paper proposes an improved probabilistic model of rebar corrosion rate and constructs a material performance deterioration model based on the uniform corrosion model of rebar and the change rule of rebar corrosion rate before and after concrete cracking.On this basis,according to the theory of analytical susceptibility analysis,a time-varying susceptibility analysis method is established for RC frame structures in offshore atmospheric environments considering chloride ion erosion,and a typical structure is constructed to analyze the time-varying susceptibility curves under different damage states and evaluate its time-varying susceptibility and damage state.The results of the study show that when the values of the ground vibration intensity index are the same,the seismic susceptibility of the structure in each damage state shows a nonlinear increasing trend in the service age,and the seismic performance is degraded continuously.When the susceptibility index is used as the structural damage index,the RC framed structure designed in accordance with China's specifications is able to satisfy China's three-performance seismic defenses in the 30 years of service age.
NETL
NSTL
万方数据
