PC与RC空心墩抗震性能试验对比  

Comparative Experiment on Seismic Performance of PC and RC Hollow Piers

作　　者：王军文[1,2] 张伟光[1,2] 艾庆华[1,2] 

机构地区：[1]石家庄铁道大学土木工程学院,河北石家庄050043 [2]石家庄铁道大学道路与铁道工程安全保障省部共建教育部重点实验室,河北石家庄050043

出　　处：《中国公路学报》2015年第4期76-85,共10页China Journal of Highway and Transport

基　　金：河北省自然科学基金项目(E2011210028;E2015210038)

摘　　要：为研究PC空心墩的抗震性能,设计制作了3个PC空心墩(1个整体式和2个装配式),并用1个RC空心墩作为对比试件,对4个试件进行了拟静力试验。基于试件的破坏特征、滞回性能、曲率分布、剪切变形等试验结果,详细比较了RC及PC整体式、PC装配式空心墩的承载力、刚度、延性、耗能、复位能力等抗震性能,分析了预应力轴压比对空心墩抗震性能的影响。研究结果表明:RC空心墩中布置无粘结后张预应力筋可以有效降低残余位移,对累积滞回耗能影响不大,但可减小等效粘滞阻尼比;布置耗能钢筋的PC装配式空心墩的自复位能力较强,曲率分布和剪切错动主要集中在墩底接缝处,其损伤程度比整体式空心墩轻的多;预应力轴压比过大可导致保护层混凝土提前被压碎,使空心墩屈服后出现负刚度。To study seismic performances of prestressed concrete （PC） hollow piers, three （one monolithic, two precast segmental） PC hollow piers were designed with one reinforced concrete （RC） hollow pier as benchmark. Cyclic quasi-static tests on four specimens were performed under a constant axial load and a horizontal load. Based on the measured failure characteristics, hysteresis behaviors, distribution of curvature and shear deformations of tested specimens, a detailed comparison of seismic performances among RC, monolithic PC and precast segmental PC hollow piers, such as the bearing capacity, stiffness, ductility, hysteretic energy-dissipation characteristics and self-centering ability were made. The effect of prestressed axial load ratio on seismic performances of hollow piers was also analyzed. The results show that RC hollow piers prestressed incorporating unbonded post-tensioned tendons at the center can reduce the residual displacement, and equivalent viscous damping ratio, while the introduced tendons have few effects on the cumulative hysteretic energy-dissipation. The precast segmental PC hollow piers with energy dissipation bars crossing the joint have a high self-centering ability, curvature distribution and shear deformation concentrated mainly in the joints at base, and lighter damage than that of monolithic hollow piers. Excessive prestressed axial load ratio can cause premature failure of concrete cover in hollow piers, and negative stiffness occurs after the piers yield.

关 键 词：桥梁工程 空心墩 拟静力试验 抗震性能 耗能钢筋 

分 类 号：U443.22[建筑科学—桥梁与隧道工程]