Experimental Research On Seismic Behavior Of Low Shear-span Ratio L-shaped Connector Composite Steel Plate And Concrete Shear Wall

In 2019,our country has approved several pilot provinces of assembled steel housing construction,and the trend of assembled steel housing promotion is more and more turbulent.Steel plate shear wall structure system has many advantages,such as economic applicability,excellent performance and so on.The research and application of steel plate shear wall structure has a huge role in promoting the transformation and upgrading of the construction industry.On the basis of grasping and referring to the related research results,continue the study of composite steel plate and concrete shear wall with L-shaped connector.Through quasi-static test and finite element analysis,the seismic behavior of the low shear-span ratio composite steel plate and concrete shear wall with L-shaped connector were studied.The main research contents and achievements are as follows:Five composite steel plate and concrete shear walls were tested under low cycle cyclic loading,the hysteretic curve,skeleton curve,bearing capacity,displacement ductility coefficient and shear deformation of the specimens were obtained.The distribution and development of the surface strain of steel columns,clad steel plates and L-shaped connectors were also discussed.The mechanical properties and failure modes of low shear-span ratio composite steel plate and concrete shear wall are studied.The influence of the L-shaped connector’s weld spacing,thickness ratio of wall and steel plate on the seismic performance has been explored deeply.The results show that: the steel plate on the surface of the specimen forms diagonal tensile bands,which eventually causes bending-shear failure.Steel plate’s local buckling is less prone to occur with weld distance of L-shaped connector decreased,the peak displacement of the specimen are increased,and the overall deformation capacity is improved.When the thickness ratio of the wall to the thickness of the steel plate is increased,the bearing capacity is greatly improved,which has little influence on the displacement ductility coefficient of the specimen,and the degradation of bearing capacity is accelerated when the peak load is reached.The finite element model of composite steel plate and concrete shear wall is established,and the differences between the calculation results and the test results are analyzed.The whole process of the stress on the wall is analyzed to verify the rationality of the model.Based on the original model,by changing the parameters of axial compression ratio,steel strength and concrete strength,the influence of them on skeleton curves and shear capacity of low shear-span ratio composite steel plate and concrete shear wall is explored.Finally,according to the test and simulation results,the shear capacity formula of composite steel plate and concrete shear wall given in the code is improved,and the shear calculation formula suitable for the composite wall in this paper is proposed.