Study On Seismic Performance Of Prefabricated Shear Wall Structures With Mixed Dry And Wet Connections

At present,the connection of horizontal joints in prefabricated shear wall structure is mainly divided into the following types according to the different connection modes: wet connection,dry connection and dry and wet mixed connection.Domestic and foreign scholars have done some in-depth research on dry and wet joints,but less on dry and wet mixed joints.Therefore,in this paper,a new type of dry-wet mixed horizontal joint is designed,and the seismic performance of the prefabricated shear wall structure and the cast-in-place shear wall structure using this joint method is studied by using the method of pseudo-static test and numerical simulation calculation analysis.The main conclusions and research results are as follows:(1)The horizontal joints of the precast shear wall structure are mixed with dry and wet joints,that is,the mixed connection of high strength bolt and connecting steel frame and metal bellows is feasible,and the structure has good seismic performance.The failure modes of precast structure and cast-in-place structure are similar,both of which show the bending and shearing failure modes.The load-bearing capacity,strength degradation and stiffness degradation of the precast structure are similar to those of the cast-in-place structure.The high strength bolt and the connecting steel frame can also transfer force effectively after the partial damage of the structure,which indicates that this kind of connection has a good effect of force transfer.(2)The influence of the distribution of high-strength bolts and connecting steel frames on the seismic performance of precast shear wall structures is obtained.Reasonable number and arrangement of high-strength bolts and connecting steel frames have little effect on the seismic performance of prefabricated structures.For prefabricated structures,the reasonable reduction of the number of high-strength bolts and connecting steel frames will slightly reduce the bearing capacity,stiffness,ductility and energy dissipation of the structure,but not by much.Therefore,the reasonable number of high-strength bolts and connecting steel frames can be reduced appropriately to simplify site construction and save construction costs.(3)The hybrid connection of high-strength bolts and connecting steel frame and metal bellows is better than the connection of all-metal bellows in terms of bearing capacity,strength degradation,stiffness degradation,ductility and energy dissipation,which further demonstrates the feasibility and advantages of the dry-wet hybrid connection.(4)The influence rules of different parameters on the bearing capacity of precast shear wall structures are summarized.Increasing the reasonable number of high strength bolts and connecting steel frames will increase the bearing capacity of the structure slightly.For the structure of YZ3(the edge component is connected by bolts and steel frame,and the middle area is connected by bellows),the larger the axial compression ratio,the greater the bearing capacity of the structure.The bearing capacity of the structure increases slightly with the increase of the strength grade of concrete.Changing the friction coefficient of concrete joints does not affect the bearing capacity of the structure.(5)The structural design method for the hybrid connection mode is put forward,and the reasonable suggestions for the site construction process of the connection mode are put forward.The paper has 49 figures,7 tables,83 references.