PC箱梁桥腹板竖向预应力筋外露段频率特性的实验研究  

Test for frequency properties of uncased part of vertical tendon in webs of a prestressed concrete box girder bridge

作　　者：杨滔[1,2] 钟新谷[1] 沈明燕[1] 

机构地区：[1]湖南科技大学土木工程施工质量与安全控制实验室,湘潭411201 [2]湖南城市学院土木工程检测中心,益阳413000

出　　处：《振动与冲击》2011年第12期201-204,215,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(51178183);湖南省科技厅重点科技计划资助项目(2011TT8183)

摘　　要：以解决目前普遍存在的大跨度预应力混凝土箱梁桥腹板竖向应力失效问题为目的,在室内建造混凝土箱梁腹板模型,完全按照现场方法安装和张拉竖向预应力筋,运用单点脉冲冲击法,基于在预应力筋外露端安置传感器所拾取的振动信号,对锚固系统外露端频率特性进行了研究,提出竖向预应力筋外露段的固结变刚度的悬臂梁模型,并对模型的螺母锚固区刚度进行识别,为竖向预应力筋张拉力测试提供了理论依据。In order to solve a problem that the vertical prestress applied widely in the webs of large-span concrete box girder bridges lost its efficacy seriously, a concert box girder web models was built in lab and vertical prestressing anchor system was installed as on site. Based on the lateral vibration signals picked up by an acceleration sensor fixed at the tip of the uncased part of a vertical tendon, using the single-pulse-impact method the frequency properties of the uncased part of the vertical prestressing anchor system were studied. A model taking the uncased part of the bar as a cantilever with a fixed end and varying fiexural rigidity was proposed, and then the flexural rigidity of the anchorage zone stiffened by the nut at the uncased part of the bar was identified. All these provided a theoretical basis for testing effectively tension retained in the vertical tendon.

关 键 词：预应力混凝土箱梁桥 竖向预应力筋 张拉力测试 

分 类 号：U446.3[建筑科学—桥梁与隧道工程]