Study On The Seismic Performance Of A New Type Of Prefabricated Composite Shear Wall

The prefabricated laminated slab shear wall structure combines the advantages of prefabricated structure,such as fast construction speed,energy saving and environmental protection and good overall performance of cast-in-place structure.It has a very broad development prospect and has become one of the main forms of prefabricated shear wall structure.However,at present,this structure is prefabricated with double-deck plates with cavities,and the thickness of the plates is also large,which has some disadvantages such as low production efficiency,self-weight,limited plane size of the components,inconvenient transportation and hoisting,etc.In this context,a new type of precast prestressed concrete composite shear wall structure is proposed in this paper,that is,two precast prestressed concrete wall panels with steel trusses are fabricated on site,and the two precast wall panels are assembled in the cavity between the two precast wall panels to form a whole after cast-in-place concrete.In order to study the seismic performance of this new type of composite shear wall,three new full-scale composite precast prestressed concrete composite shear wall specimens with axial compression ratio of 0.28 and one cast-in-place shear wall specimen were designed and manufactured,and the low-cyclic repeated load tests were carried out on them.The seismic performance indexes of new precast prestressed concrete composite shear walls and cast-in-place shear walls,such as bearing capacity,ductility coefficient,stiffness degradation and energy dissipation capacity,were compared and analyzed.The influence of different edge member forms and prestressing of steel bars in prefabricated panels on the seismic performance of new precast prestressed composite shear walls was studied.On the basis of the test,the finite element software ABAQUS was used to establish a three-dimensional model of the new precast composite shear wall,which was compared with the test results.At the same time,the influence of concrete strength on the mechanical performance of the shear wall was studied by changing the strength grade of precast slab concrete with ABAQUS.The results show that the failure types of the new precast prestressed concrete composite shear wall specimens are the same as those of the cast-in-place shear wall specimens,both of which are bending shear failure.The peak bearing capacity of the new prefabricated composite shear wall is similar to that of the cast-in-place shear wall,the displacement ductility coefficient is smaller than that of the cast-in-place composite shear wall,and the energy dissipation capacity of the new prefabricated composite shear wall is better than that of the cast-in-place composite shear wall.The application of prestress in the prefabricated wall can reduce the shear deformation and effectively control the occurrence and development of inclined cracks,but it has no obvious effect on the seismic performance of the new prefabricated composite shear wall.Casting end edge components in situ can better guarantee the overall performance of composite shear wall.The higher the strength grade of precast wall concrete,the higher the bearing capacity of the specimen,but the faster the stiffness degradation.