Experimental Study On Shear Behavior Of Epoxied Joints In Segmental Precast Concrete Members With Multi-Shear Keys Under The Nonuniform Normal Stress

The precast segmental precast concrete bridges have a lot of advantages including fast construction speed,good quality of bridge beams,little disturbance to the existing traffic under the bridge,energy saving and environmental protection etc.,the application of engineering is increasing.Among them,the segmental precast concrete bridges with epoxied joints have been widely promoted because of its good durability.The discontinuity between reinforcement and concrete at the joint is the key structure of segmental precast concrete bridges.In this paper,the experimental study on shear behavior of epoxied joints in segmental precast concrete components is carried out,the main work and conclusions are as follows:(1)Considering the influence of the nonuniform normal stress level(1?4MPa?2?3MPa?1?5MPa?2?4MPa and 4?5MPa)and the surface roughness of joint(chipping or not chipping),15 segmental precast concrete components with epoxied joints were designed and made,then the static load test was carried out.The failure data,displacement and strain data were recorded in detail during the test.(2)Direct shear failure at the joint occurs in the plain concrete area around the joints,there is no obvious slip between the joints at the time of destruction,the integrity of the segmental precast concrete component is better,and the process of destruction is short,and it is fragile.(3)The normal stress level has a significant effect on the direct shear capacity of joints,the higher the normal stress level,the greater the bearing capacity;the greater the degree of irregularity of normal stress,the smaller the bearing capacity.(4)It doesn't have obvious effect on the bearing capacity of the joints direct shear to chisel the concrete surface on both sides of the joints for the sake of changing the roughness of the joint surface.(5)Finite element analysis software ABAQUS is used for numerical simulation of test components,the stress state of concrete in the weak area at the joint is analyzed in detail.Compared with the experimental data,the two are in good agreement.(6)Based on experimental and numerical simulation results and combined with the field situation of the Zhou Huai bridge on Zhengfu railway,suggestions for quality control of segmental precast concrete bridges are put forward.