全装配混凝土模块结构竖缝螺栓连接面外受拉性能试验研究OA

The structural performance of modular buildings depends largely on the overall performance of their joint connections.This paper takes bolt-connected vertical joints of fully assembled modular construction-reinforced concrete(FAMC-RC)as research objectives,and a series of out-of-plane uniaxial tensile tests are conducted out on 10 groups of full-scale specimens of individual bolted vertical joints.The results show that under the action of tensile loading,the vertical joint may exhibit failure modes such as eccentric bending failure of a beam,punching shear failure of the plate,combined flexural and punching shear failure of the plate,and shearing failure of the plate.The damage process mainly undergoes four stages of prestressing loss,elastic loading,elastic-plastic development,and brittle damage.The mechanical properties of the joints are influenced by the distance D1 to the ribs,the length L of the connecting wall,and the embedded steel plate.The presence of ribs contributes to improving the out-of-plane bearing capacity of the joints,and the enhancement effect of the rib decreases with the increase of D1.The length L of the connecting wall is sufficient to make the punching cone fully carried out,and the punching ring is complete.The embedded steel plate in the joint region can obviously increase the bearing capacity,deformation capacity,and stiffness of the test specimen,but the increase in the size of the embedded part does not have a significant effect on the mechanical properties of the test specimen.Based on the above test results,the project suggests that:the distance D1 from the joint to the rib should be less than 485 mm,the length L of the connecting wall should be more than D1+300 mm,and,to reduce the amount of material,the V1-shaped embedded part is preferred.In this paper,for the punching damage mode,considering the concrete plate,reinforcement,and embedded steel plate of the three common anti-punching roles,a bearing capacity formula is proposed for the joint punching damage.The comparison with the test value concludes that the calculation formula is conservative.Taking into account the greater variability of the concrete material,the formula of the security reserve is high,and the calculation method is basically reasonable.