Study On The Mechanical Performance Of Dry Vertical Connection Of Recycled Clay Brick Aggregate Concrete Structure Wall

With the continuous advancement of urbanization and the gradual approach of the building’s service life,the early brick-concrete structure was continuously demolished.The main processing method of dismantled waste clay bricks is to landfill or crush them into aggregates for making non-load-bearing blocks.Landfilling will take up increasingly tense land resources;using waste clay bricks for the production of non-load-bearing blocks cannot maximize the use of solid construction waste.This paper considers the dismantled waste clay bricks to be broken into recycled brick aggregates for the production of recycled brick aggregate concrete(RBAC)and RBAC structure walls,which are used as load-bearing parts of the building structure to expand the use of waste clay bricks.Circulating application range.These RBAC structural walls are assembled into a whole structure using simple connection methods and applied to the construction of multi-storey village and town building structures(3 to 4 floors).In general,the construction conditions of villages and towns are limited,and the traditional wet connection has certain limitations.However,the dry connection is simple to operate,short construction time,and less wet work.Therefore,this article considers its application to RBAC structure walls.The vertical seams between the walls are connected.In this paper,the seismic performance test of RBAC structure walls with dry vertical connections is conducted,and the mechanical performance of the dry vertical connections under earthquake action is studied.The main research contents and conclusions include:(1)Through low-cycle repeated tests on 6 specimens of dry vertical connection of RBAC structural walls and 1 specimen of full-section RBAC structural wall,research on the embedded hole with pipe of RBAC,concrete outsourcing C-shaped steel,number of bolts,bolt specifications and the addition of nitrile rubber between the joints affect the mechanical properties of the connection.The test results show that the failure process of each test piece is similar,showing different degrees of shear failure;pipe,bolt specifications and nitrile rubber have an effect on the crack distribution form of the test piece;C-shaped steel and the number of bolts will affect the test piece the distribution range of the test piece.(2)The horizontal deformation composition,steel bar strain,steel plate strain,concrete strain and seismic performance of the specimens are analyzed and researched.The specimen is mainly shear deformation,and different research parameters have an influence on the deformation composition of the specimen;the analysis results show that the rigidity and ductility of the dry vertical connection specimens are weaker than that of the full-section structural wall;the energy dissipation performance of the dry vertical connection is slightly better than that of the full-section specimens.The existence of pipes can improve the deformation ability of the test piece;outsourcing C-shaped steel on both sides of the joint and increasing the bolt specifications can improve the stiffness and energy consumption performance of the test piece;increasing the number of bolts can significantly improve the stiffness of the test piece;the presence of nitrile rubber will reduce the stiffness of the test piece,and it does not make much contribution to the energy consumption performance of the test piece.In the engineering design,the design method of outsourcing C-shaped steel on both sides of the vertical joint,increasing the number of bolts and increasing the bolt specifications can be adopted.(3)The applicability of the calculation formula for the bearing capacity of the structural wall in the code is verified in the dry vertical connection of the RBAC structure wall;and the applicability of the calculation formula of the steel structure high-strength bolt in the dry vertical connection is compared.The calculation results show that the calculation and construction theory of high-strength bolts in steel structures are suitable for the calculation of bolt forces in dry vertical connections,and revised formulas for calculating the bearing capacity of the normal section and the oblique section of the RBAC structure wall adopting dry vertical connection is proposed.It provides a reference for the application of dry vertical connection in prefabricated buildings.