Mechanical Performance Analysis Of Mixed Reinforced Shear Wall With Horizontal Slits At The Bottom

With the development of the national economy,more and more high-rise buildings are rising from the ground,and the shear wall structure is widely used in actual projects because of its excellent seismic behavior.While the traditional shear wall structure can no longer meet the needs of multi-functional development of buildings,it is particularly important to study the multi-functional shear wall structureIn this paper,a mixed-reinforced shear wall structure with horizontal slits at the bottom was studied,and four shear walls were designed and fabricated to conduct a pseudo-static test.Considering opening the slits at the bottom of the shear wall and adding FRP bars in the center of the embedded column at both ends and cuting the outer longitudinal bars of the embedded columns at both ends to study its mechanical performance under repeated loading.At the same time,the finite element software ABAQUS is used to model and analyze the shear wall under various conditions,and compare the test results with the simulation results.The main conclusions are as follows:(1)It can be seen from the experimental phenomenon of 4 shear walls that the shear wall FRPSW-1 has FRP bars added to the center of the embedded columns at both ends,so that after reaching the peak load,the bearing capacity decreases slowly,and the shear wall FRPSW-2 leads to the development of cracks in the wall because of the horizontal slits in the corners,and a penetration slit appears at the bottom of the wall when the shear wall breaks,the shear wall FRPSW-3 cuts the outer longitudinal bars of the embedded columns at both ends,which is effective has contained the development of cracks and concentrated mainly on the middle and lower parts of the wall;(2)The hysteresis curves of the shear walls SW and FRPSW-1 are relatively narrow and long,and the shear walls FRPSW-2 and FRPSW-3 with horizontal slits are full of hysteresis curves,indicating that their energy dissipation capacity has been greater.It can be seen from the skeleton curve that the peak loads of the shear walls FRPSW-2 and FRPSW-3 have been significantly reduced;(3)The stiffness degradation trend of each shear wall is relatively close.During the whole test process,the stiffness degradation at the initial stage of loading is faster,the slope of the curve is larger,and the crack development tends to be stable at the later stage of loading,and finally tends to be smooth;(4)Opening horizontal slits in the corners is very helpful to increase the ultimate displacement of the shear wall,and increases the displacement ductility coefficient of the shear wall.The shear wall FRPSW-3 has an increased displacement ductility coefficient compared with the shear wall SW nearly 50%,especially that the cutting of the outer longitudinal bars of the embedded columns at both ends has greatly improved energy dissipation;(5)The energy dissipation capacity of each shear wall is evaluated by the energy dissipation coefficient and the equivalent viscous damping coefficient.The calculation results prove that the energy dissipation capacity of the shear wall FRPSW-3 is the best,and the energy dissipation in the whole loading process has the fastest growth rate;(6)The strain data of this test was collected by a strain gauge,and three representative locations were selected from which to analyze the strain development law,which was consistent with the results reflected by the test phenomena of each shear wall;(7)Through the finite element software ABAQUS,the numerical simulation of this test was carried out,comparing the concrete stress,steel bar stress,FRP bar stress and concrete damage,and found that the results were basically consistent with the results presented by the test phenomena,and the test skeleton curve compared with the simulated skeleton curve,the curve fits higher overall,which proves the effectiveness of this simulation,and analyzes the parameters of the shear wall to study the influence of different variables on the mechanical performance of the mixed-reinforced·shear wall with horizontal slits at the bottom.