套筒连接的预制拼装桥墩抗剪性能试验

为了探究采用灌浆套筒连接预制拼装桥墩的抗剪性能和影响因素,对拼接缝位置、截面中心增设无黏结预应力筋、拼接面增设剪力键齿的预制拼装桥墩试件及现浇混凝土桥墩试件进行了拟静力试验.分析比较了试件的损伤发展过程和最终的破坏模式.从滞回曲线、极限剪切承载力、变形等方面探讨了试件的抗剪性能,并与现浇混凝土试件的抗剪性能进行了比较.试验结果表明,采用灌浆套筒连接构造的预制拼装桥墩主要表现为弯剪破坏模式,变形能力和耗能能力良好,且与现浇试件抗剪性能相近.截面中心增设无黏结预应力筋的试件,可提高抗剪承载力,并降低了残余变形.

Experimental Study of Shear Performance of Precast Segmental Bridge Piers with Grouted Splice Sleeve

In order to study the factors such as the joint position, unbonded prestressed tendons, shear keys affecting the shear performance of precast segmental bridge pier with grouted splice sleeve, quasi static tests of four precast segmental bridge piers and one cast in place concrete pier were conducted. The damage development and failure mode of models were discussed. Their shear performance was summarized by analyzing hysteresis curves, ultimate shear capacity, displacement capacity. The shear performance of precast segmental bridge pier was compared with the cast in place concrete specimen. The experimental results show that the failure mode of precast segmental bridge pier with grouted splice sleeve was bending shear failure. The precast segmental bridge pier has a good displacement capacity and energy dissipation which is similar to the shear performance of cast in place specimen. Adding unbonded prestressed tendons in the center of the section increases the shear bearing capacity and reduces the residual deformation.