Experimental Research On Seismic Performance Of Superimposed Slab Shear Wall With New Horizontal Connection

The stucture system of superimposed slab shear wall goes in line with the development direction of the modernization of the construction industry with high degree of factory,site construction convenience,simplicity of controlling product quality and environmental protection.However,because of its late introduction time,the development in China is not mature.There is still less research on its horizontal connection.The assembling monolithic precast concrete shear wall structure system,which was put forward by the Harbin Institute of Technology Project,is connected by rebar ring-bar as the horizontal connection,and has been proved to have good mechanical performance through the experiment and the practical engineering.The purpose of this paper is to apply rebar ring-bar connection to superimposed slab shear wall,to the advantages and disadvantages of the mechanical properties and construction methods,3 new types of horizontal rebar connections are proposed,that is,the buckle tendons connection and the spiral hoop bar connection.The specific research contents are as follows:1.In order to explore the connection performance of 3 kinds of new type of horizontal bar connection and rebar ring-bar connection,considering the effect of horizontal reinforcement ratio,6 superimposed slab shear wall splicing specimens and 2 cast-in-place shear wall specimens are designed and fabricated,and the connection performance test under cyclic shear action is carried out.Through the failure state of the specimen,the hysteresis curve and the strain of steel bar,it is found that 3 kinds of new type of horizontal rebar are connected by force,which buckle tendons connection is convenient to use and is more feasible.2.In order to further clarify the construction method and the seismic performance of the superimposed slab shear wall with horizontal joint,3 superimposed slab shear walls and 3 pieces of the same size reinforced concrete wall was designed and fabricated.Through the comparison and analysis of the specimen’s making process and the test results,the results show that the buckle tendons connection is more convenient and quicker in the construction process than the reinforcement ring-bar connection.Compared with cast-in-place shear wall specimens,the bearing capacity of superimposed slab shear walls is slightly lower,the ductility is increased by 13%,and the energy dissipation capacity is increased by 56%.When the horizontal force reaches the peak load,the straight surface shear failure or oblique section shearing failure has not occurred at horizontal connection,which proves that it has good seismic performance.3.Combined with the connection performance test and pseudo static test,this paper deeply studies the failure mechanism of horizontal connection direct shear failure and oblique shear failure,and presents the calculation formula for shear bearing capacity of straight surface and oblique section by analyzing experimental phenomena and data.The experimental results are compared with the theoretical formulas to verify that it is reliable for practical engineering design.Finally,the construction requirements and suggestions for the design of uperimposed slab shear wall with buckle tendons connection are put forward.