Seismic Vulnerability Analysis Of Loess Foundation And Multi-Ribbed Composite Wall Structure Based On IDA Method

As a green new energy-saving sesmic building structure system,multi-ribbed composite wall structure has many features,such as light,energy saving,environmental protection,thermal insulation shock absorption,with the construction speed,economical and practical characteristics.When the multi-ribbed composite wall structure is seismic designing,it is generally assumed that the foundation of the structure is a rigid foundation.But the soil and the structure are interacted under the earthquake load,and the foundation soil will have an influence on the dynamic response of the structure.The seismic vulnerability analysis can describe the relationship between the failure probability of the structure under different ground motion intensity and the corresponding ground motion intensity from the whole point of view,and quantitatively analyze the seismic capacity of the structure from the probabilistic sense.Therefore,the seismic vulnerability analysis of the multi-ribbed composite wall structure,which is considering the foundation soilstructure interaction(SSI),has theoretical and practical significance to structure seismic design.Based on the National Natural Science Foundation of China,this paper conducted a shaking table test on the interaction of loess foundation and multi-ribbed composite wall structure.Through the numerical simulation of the prototype of the test model,the calculated results are in agreement with the experimental results.On this basis,the seismic vulnerability analysis of the multi-ribbed composite wall structure based on the IDA method and considering the interaction between soil and structure is carried out.The main research contents are as follows:(1)Based on the 1:15 scale multi-ribbed composite wall structure housing model shaking table test which is simulating earthquake,the prototype and model,the layout of the measuring point,the loading procedure and the part of the experimental phenomenon and the result are introduced.The numerical model is established and the correctness of the model is verified by the experimental data.The experimental results show that the model is in good agreement with the experiment in terms of the wave type and the peak.The model lays the foundation for the finite element dynamic time history analysis of the multi-ribbed composite wall structure.(2)The method of selecting seismic wave is discussed,the appropriate seismic strength index and structural damage index are determined.The dynamic response analysis of the interaction test prototype structure is carried out by incremental dynamic analysis method.The IDA curve cluster of multi-ribbed composite wall structure which is considering SSI is obtained.The displacement limit of the structure in each performance limit state is given.The dynamic characteristics and seismic capacity of the loess foundation and multi-ribbed composite wall structure under different ground motions are studied from the elastic and elastoplastic stage to the structural collapse.The relationship between ground motion intensity and structural behavior is studied from the macroscopic point of view,which provides the basis for structural seismic vulnerability analysis.(3)Based on the basic principle of seismic vulnerability and the results of incremental dynamic analysis,the vulnerability curves of the multi-ribbed composite wall structure considering SSI are drawn,and the three limit state exceeding probability and structural failure probability corresponding to four failure states are obtained.And provide a reference for the risk assessment of the structure in the event of an earthquake.The high order polynomial function is used to fit the vulnerability curve and the structural failure probability curve,and the sensitivity of the seismic demand parameter is analyzed,which provides a reference for the seismic design calculation of the loess foundation and multi-ribbed composite wall structure...