Seismic Behavior Research Of Precast Shear Wall With Vertical Reinforcements Grouted And Splicing Joints

In recent years,in the context of China’s construction industry’s implementation of "four sections and one environmental protection" and the industrialization of buildings and industrialization of housing,fabricated shear wall structures have flourished.For prefabricated shear wall structure,related research shows that the reliable and effective connection at its joints is still the focus of prefabricated shear wall structure research.In order to further promote the practical engineering application of prefabricated shear wall structure,improve the joint connection performance and seismic performance of prefabricated shear wall structure with mortar anchor connection,expand the scope of application of precast shear wall structure with mortar anchor connection(target application is larger Applicable height and medium and high intensity fortification zone)Based on a lot of reading of domestic and foreign literature,this paper relies on the Hunan Provincial Department of Education project "Study on the Structural Performance of Assembled Concrete Double-Shear Shear Wall(16C0647)" and the launch of scientific research by Hunan University of Science and Technology Fund project "Earthquake resistance of prefabricated concrete double-plate shear wall(E51695).Through the combination of experimental research and finite element analysis,the vertical reinforcement through structural improvement(introduction of buckling and closing stirrups in edge members)was studied.Seismic performance of mortar anchored prefabricated shear wall,the main research contents and results are as follows:(1)Three shear wall specimens were designed and completed,and subjected to low-cycle repeated load tests.The test results show that the vertically connected rebars of the assembled specimens can effectively transmit stress and connect reliably with high-strength grouting.The use of buckled closed stirrups can improve the concrete restraint performance of the edge members at the end of the shear wall;the vertical prefabricated shear wall structure with vertical reinforced mortar anchoring can achieve the same or similar load bearing capacity,stiffness,ductility and energy consumption as the cast-in-situ structure.It can reach the applicability and seismic safety equivalent to the cast-in-situ shear wall structure in the middle and high intensity fortification zone,which is worthy of further research,promotion and application.(2)Nonlinear finite element analysis of cast-in-situ shear wall specimens and vertical reinforced grout-anchor prefabricated shear wall specimens under low-cycle cyclic loading using ABAQUS.The damage plasticity of the concrete and the old and new are considered in the model.The effect of bond slip at the interface of concrete,combining the new and old concrete bonding theory with the cohesion model in ABAQUS,the results show that the finite element analysis results are basically close to the test results,which shows that the model built by large-scale finite element software ABAQUS,The correctness of the selected material constitutive relationship and interface analysis method has verified the reliability of the finite element model and provided a finite element analysis method for the mortar-anchored fabricated shear wall.(3)According to the reliable finite element model and analysis method mentioned above,the axial compression ratio,aspect ratio,concrete strength,edge vertical reinforcement diameter,vertical connection reinforcement diameter,and stirrup strength are used as parameters to change the vertical reinforcement.Exploratory analysis of the seismic performance of the mortar anchored prefabricated shear wall,the results show that increasing the axial compression ratio and the diameter of the vertically connected steel bars can improve the bearing capacity of the structure;reducing the aspect ratio will make the structure tend to shear failure;The strength of concrete and the diameter of the vertical steel bars at the edges have a certain effect on the bearing capacity of the structure;the strength of the closed stirrup has almost no effect on the seismic performance of the structure;appropriate engineering recommendations are given based on the analysis results.