Seismic Fragility Analysis And Shaking Table Test Verification Of Connected Structure With Large Span Special-shaped Steel Corridor

The large-span shaped steel corridor connected structure is a commonly used structural form in the building.It not only satisfies the requirements of use function,but also makes the building more beautiful.However,due to its special structural system,the force is more complicated,and the structure suffers from varying degrees of damage in strong earthquakes.In order to study the seismic performance of the large-span shaped steel corridor connected structure under different ground motion intensity,24 ground motion records were selected,and PGA was used as the ground motion intensity index,The maximum inter-story drift ratio?,shear strain?_a and damage factor d are used as the damage indicators of the main building and the affiliated building I,the isolation bearing and the embedded anchoring end of the corridor.The incremental dynamic analysis of the connected structure is carried out to obtain the IDA curves of the local structure.Then the vulnerability curve of each local structure and the connected structure system is drawn according to the IDA curve,and the seismic performance of the connected structure under different ground motions intensity is studied according to the vulnerability curve.Finally,the model and vulnerability analysis results were verified by shaking table test.The main conclusions obtained in this paper are as follows:(1)Referring to the test and strength calculation method of the embedded parts of the tension,bending and shearing in the relevant literature,the damage factor d of the embedded parts is defined,and the damage state of the anchoring embedded parts end of the angled steel is divided and quantified by the damage factor d.(2)According to the vulnerability curve and vulnerability matrix of the local structure,under the same ground motion intensity,the most vulnerable local structure of the connected structure are:the pre-embedded anchoring end of the corridor,the main building,the affiliated building I and the isolation bearing.The damage probability of the connected structure system is greater than the damage probability of each local structure.It is unsafe to evaluate the vulnerability of the connected structure by using the vulnerability of the local structure.(3)It can be seen from the shaking table test phenomenon that under the same ground motion intensity,the failure sequence and damage degree of each local structure in the test were the same as the vulnerability analysis,which verified the correctness of the vulnerability analysis.(3)The weak part of the connected structure exists in the pre-embedded anchoring end of the junction of the corridor and the affiliated building I,which is easily damaged in the earthquake.It is recommended to strengthen the anchor to ensure a reliable connection or to add a viscous damper at the joint to reduce the seismic response of the corridor.