Research And Analysis On Shear Resistance Of Vertical Joints Of Precast Shear Wall

Due to the advantages of high labor efficiency,less pollution and controllable quality,industrialization in housing has gradually spread.As an important part of housing industrialization,precast shear wall structure has gradually attracted people's attention.However,the reliability of the shear wall joint is an important factor affecting the safety of precast shear wall structure.Either not all the effects influencing the shear strength of the joint were taken into consideration by foreign relevant codes,or the effects were reduced in spite of them being considered.In addition,the shear resistance of the vertical joint of precast shear wall in foreign researches didn't fully consider the special characteristics of shear strength of joints in precast shear wall.In view of the above problems,this paper carried out the following research.In this paper,static tests of four samples were carried out,and relevant tests data was analyzed.The research shows that the relation between load and displacement can be treated as a linear relationship before reaching its peak while concrete shear plays a major role in this approximately linear stage.Concrete shear resistance begins to quit work in the nonlinear stage.The relation between load and displacement of rebar shear friction effect can be treated as quadratic parabola before the rebar shear friction effect reaches its peak load.In this paper,calculating formulas of four kinds of effects which include shear friction effect,dowel action,concrete shear and pressure were given,and the four kinds of effects were combined.The theoretical results of this method were close to the test results.The method can reflect the shear resistance of vertical joints.In this paper,finite element analysis of shear bearing capacity of rebar was carried out with different effective thickness of concrete and different strength of concrete.The range of rebar diameter was 8~20mm.The increase of the diameter of rebar is in favor of the increase of shear capacity of joints in a certain range.The increase of effective thickness of concrete is beneficial to the shear of rebar.The increase of concrete strength can increase the shear strength of the joints to some extnet,but the effect of lagre diameter rebar has larger effect than that of small diameter rebar.The rebar at the vertical joints only needs a basic anchorage length,so that the rebar can bear complex external force.Excessive increase in length can not improve shear capacity.Finally,the results of finite element model were compared with the relevant calculation formulas,and design proposal was given.