Shaking Table Tests Of A Slab-wall Structure Incorporating Steel Tube-confined Concrete Shear Wall

The reforcement concrete(RC)slab-wall structures replace the beam-slab floor system with a flat-floor system,which meets the requirements of aseembled integral construction and current development of China’s industrialization of buildings.However,the shortcoming of the structure is that the flat-floor system is complicated in load bearing.Due to the elimination of coupling beams,the limb wall becomes a single wall,because of which,only the plastic deformation of the shear wall consumes energy under rare earthquakes,causing the cutbacks of structural seismic ductility.The advantage of the steel tube-confined concrete(STCC)shear wall is its high anti-torsion as well as anti-side stiffness and high seismic ductility.Hence,replacing the ordinary RC shear wall with STCC shear wall may solve the problem of insufficient seismic ductility of the ordinary RC slab-wall structure.In order to study the seismic performance of the innovative slab-wall structure incorporating STCC shear wall,this paper designs and produces a typical 1:8 scale model and conducts earthquake simulation shaking table tests of 4 seismic intensity levels namely 7 degree frequent,7 degree basic,7 degree rare and 8 degree rare earthquake.The seismic damage,dynamic characteristics and macroscopic seismic responses like acceleration response,displacement response and seismic inertial force of the model structure under different seismic intensity levels tests are obtained.Then the cprresponding seismic responses of the prototype structure are obtained according to the similitude law.On the basis of shaking table tests,the finite element models of prototype structure and the ordinary slab-wall structure are established respectively,and nonlinear time history analysis and Pushover analysis are carried out to directly compare the two different slab-wall structures.The test results show that the innovative structure exhibits high seismic stiffness under frequent earthquakes.Under rare and very rare earthquakes,the elastoplasticity of structure is fully developed,showing good seismic ductility.The maximum elastic and elastoplastic drifts are wthin the limit of current codes.Generally,the innovative slab-wall structure incorporating STCC shear wall meets the the performance requirements of current seismic code.Under rare earthquakes,no damage was found in the STCC shear wall,whose good seismic performance and seismic ductility effectively solved the problem of insufficient seismic ductility of the ordinary RC slab-wall structure after the elimination of coupling beams.Seismic damage concentrated on the slab-wall connection,the cumulative development of cracks on which leaded to an attenuation in structural stiffness.The slab-wall connection is the seismic weakestlink of the structure.It is recommended to use particular reinforced details to improve the internal force distribution,the bearing capacity of the connection.The results of numerical simulation analysis show that the finite element model corresponding to the prototype structure can effectively reflect the structural and dynamic characteristics of the prototype structure,and the analysis results are representative and of reference value.Compared with the ordinary slabwall structure,the innovative slab-wall structure incorporating STCC shear wall exhibits slower stiffness degradation,higher ultimate bearing capacity,better ductility as well as better seismic performance under earthquake.