Study On Seismic Performance Of RC Frame Structure With Infilled Wall In Exterior Corridor

Multi story RC infilled wall frame structure is widely used in public buildings in China.In the 2008 Wenchuan earthquake,6 of the 14 teaching buildings in Xuankou middle school collapsed,including 5 frame structures and 1 brick concrete structure.Among them,the four collapsed frame structures are unequal span exterior corridor frame structures with infilled walls.Based on the existing shaking table tests,this paper explores the seismic failure mechanism of this kind of typical structure;carries out theoretical and numerical simulation research,and puts forward the stiffness balance design method considering the infilled wall;according to this design method,the seismic collapse resistance of the prototype structure is improved by adding wing walls.(1)By using the modeling method of equivalent diagonal brace + ABAQUS beam element + PQ-Fiber,two numerical models of pure frame model and exterior corridor frame structure with infilled wall are established.The strain,horizontal shear and plastic hinge development of the bottom column of the two models are compared and analyzed,the earthquake collapse failure test of the vibration platform with infilled wall exterior corridor frame structure made by this research group is verified,and the failure mechanism of the exterior corridor frame structure.The results show that: the actual stiffness of the structure is uneven due to the setting of the half height infilled wall,which makes the horizontal seismic shear distribution uneven.The restraint effect of the half height infilled wall on the column has a great impact on the collapse mode of the exterior corridor frame structure.(2)This paper collects and collates the calculation formulas of elastic lateral stiffness of fully filled wall and half height infilled walls proposed by domestic scholars,and verifies the rationality of the formulas by using the measured values of elastic lateral stiffness of fully filled wall and half height infilled walls.Combined with the test data and the calculation formula of the elastic lateral stiffness of the infilled wall,the calculation formulas of the lateral stiffness of the fully filled wall and the half height infilled wall in the yield stage and the peak bearing capacity stage are obtained.By adding wing wall to balance the stiffness of the structure model with infilled wall,the size of wing wall to be added in different elastic and elastic-plastic stages is determined,and the design method of stiffness balance is proposed.(3)Based on the teaching building of Xuankou middle school,four frame structures(one prototype exterior corridor frame structure and three wing wall reinforced exterior corridor frame structure)are designed.The IDA analysis and collapse resistance analysis of the four model structures are carried out.The results show that the proposed stiffness balance design method can improve the seismic adverse effects of the exterior corridor frame structure caused by unreasonable setting of infilled walls.