干接缝节段拼装桥墩振动台试验研究  

SHAKE TABLE TESTS OF SEGMENTAL BRIDGE COLUMNS WITH MATCH-CAST DRY JOINTS

作　　者：葛继平[1] 王志强[2] 

机构地区：[1]上海应用技术学院城市建设与安全工程学院,上海200235 [2]同济大学桥梁工程系,上海200092

出　　处：《工程力学》2011年第9期122-128,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(50508032);铁道部科技开发项目(2010G007-J);上海市教委优青基金项目(YYY09007)

摘　　要：为探讨节段拼装桥墩的抗震性能,设计了一个包含5种不同类型混凝土桥墩的试验方案,其中3种为节段拼装桥墩,其余2种分别为整体现浇钢筋混凝土桥墩和无粘结预应力混凝土桥墩。采用振动台试验方法比较分析了这5种不同构造类型混凝土桥墩的动力特性,损伤的发展过程,接缝的扩展规律,相同加速度激励下的最大位移响应等,总结了不同类型桥墩的地震响应特点和规律。试验结果表明:节段拼装预应力混凝土桥墩的破坏现象主要是塑性铰节段墩底接缝的张开,塑性铰节段墩身没有发生损伤现象,随输入增加,接缝张开程度逐渐增大,表现为明显的摇摆现象。在相同输入下,节段拼装试件的最大位移响应大于同等整体现浇钢筋混凝土试件。耗能钢筋的存在可以增加桥墩的侧向刚度,减小最大位移响应,延缓接缝的张开,增加结构的耗能能力。有粘结预应力筋的存在,使得节段拼装桥墩在较大输入激励下,预应力筋易发生屈服,从而导致位移响应急剧增大。To investigate the seismic performance of precast segmental bridge columns, an experiment including five concrete bridge columns was designed; among them three were precast segmental bridge colunms and the other two were cast-in-place bridge columns. Through the shake table test under the same peak gravity acceleration （PGA）, the seismic behaviors of the five concrete bridge columns were demonstrated including the dynamic properties, the damage process, the opening of the joints and the displacement response. Results showed that, for the three precast segmental bridge columns, significant flexural cracking occured at the joints in the plastic hinge zones while no cracks were observed in the body of segmental column. With the increasing of the excitation, the opening of the joints became larger showing the swaying phenomenon. The displacement response of the precast segmental bridge column was larger than that of the conventional cast-in-place reinforced concrete bridge column. The existing of energy-dissipating bars increased the stiffness, mitigated the displacement response, delayed the opening of joints and dissipated more energy. For the precast segmental bridge column with the bonded prestressing strands, the displacement response increased significantly due to the yielding of prestressing strands under large earthquakes.

关 键 词：节段拼装 干接缝 振动台试验:耗能钢筋 抗震性能 

分 类 号：P315.5[天文地球—地震学] U443.22[天文地球—固体地球物理学]