| Prefabricated monolithic composite shear wall structure system is a semi-prefabricated and semi-cast-in-place structure system that widely used in multi-storey and high-rise buildings,also known as prefabricated concrete double-slab structure system or composite slab shear wall structure system.The composite wallboard is mainly composed of inner and outer prefabricated wallboard on both sides and central post-poured concrete layer.The prefabricated wallboard on both sides is mainly connected by triangular truss reinforcement.Prefabricated composite shear wall system has the advantages of light weight,strong structural integrity,good waterproofing effect of joints,factory production combined with thermal insulation materials,energy saving and environmental protection,etc.It is a promising assembly concrete building structure system.In this paper,the bearing capacity and deformation capacity of single-sided composite shear wall and double-sided composite shear wall under out-of-plane loads are studied by carrying out out out out out out out out out out out-of-plane mechanical tests and relevant theoretical analysis of composite shear walls with different horizontal joint connections.The following research contents are mainly completed:(1)Full-scale shear wall specimens are designed and fabricated in factory and relevant experimental work is carried out to study the failure modes,initial stiffness,stiffness degradation,ductility and bearing capacity of single-sided composite shear wall and double-sided composite shear wall under out-of-plane bending with different horizontal joints,and compare the experimental results with cast-in-situ shear wall.Horizontal joints of composite shear walls are connected by vertical steel bar overlap and vertical steel bar insertion overlap of prefabricated wall panels.The influence of screw stirrups on the two kinds of horizontal joints is considered.(2)The test results showed that bending failure occurs when shear wall specimens are subjected to out-of-plane loads.The initial stiffness,ductility and ultimate bearing capacity of single-sided composite shear wall and double-sided composite shear wall specimens are greater than those of cast-in-situ shear wall specimens;SPCW-2 specimens of single-sided composite shear wall and DPCW-2 specimens of double-sided composite shear wall specimens with horizontal joint connections specified in Appendix A of GB/T 51231-2016 are adopted.Connecting steel bars have good load transfer performance,and the setting of spiral stirrups has little influence on the out-of-plane bending capacity of composite shear walls.(3)Through finite element modeling,the similarities and differences between finite element simulation results and test results are analyzed,and the rationality of finite element model is verified.Through finite element variable parameter analysis,the contents not involved in the test are supplemented.The process of out-of-plane bending force transfer of cast-in-place shear wall and composite shear wall is briefly analyzed,and the calculation formula of out-of-plane bending capacity is put forward.(4)The finite element simulation results are in good agreement with the test results.The finite element simulation results show that the stress process of the vertical connecting steel bars of composite shear walls is less different from the test results,and the finite element model is reasonable.When the spacing of the vertical connecting steel bars along the width of the wall is reduced,the initial stiffness of the composite shear walls does not change much,and the ultimate bearing capacity can be improved to a certain extent.In the analysis of out-of-plane bearing capacity of composite shear wall,1.2-1.3 times increase coefficient is proposed to consider the effect of vertical reinforcement in truss reinforcement and prefabricated wall slab on its overall performance and flexural bearing capacity.Finally,on the basis of summarizing the results of this study,some problems that need to be further studied are proposed. |
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