箱梁竖向预应力张拉力无损检测方法  

Nondestructive testing method of vertical prestressed reinforcement tension in box girder

作　　者：孔存芝 周大全[2] 张峰[3] 杨为民[3] 孙家龙[3] 龙屹宇 

机构地区：[1]山东高速四川产业发展有限公司,成都610225 [2]中交第一公路勘察设计研究院有限公司,西安710075 [3]山东大学岩土与结构工程研究中心,济南250061 [4]长沙理工大学土木与建筑学院,长沙400114

出　　处：《中国科技论文》2013年第11期1136-1140,共5页China Sciencepaper

基　　金：高等学校博士学科点专项科研基金资助项目(20100131120042;20100131120046)

摘　　要：由于竖向预应力张拉力损失过大,预应力混凝土连续箱梁桥的箱梁腹板斜裂缝现象较为普遍。为了能有效检测竖向预应力筋的实际张拉力值,将竖向预应力钢筋的外露段视为分析体,把钢筋视作刚体,锚固段用环形刚臂外加环形的弹性支承模拟。竖向预应力筋张拉力发生变化时,空间弹性支承的刚度和钢筋的自振频率也会发生相应变化,利用钢筋自振频率的变化反映有效张拉力值。结合模型试验数据,建立了精轧螺纹钢筋竖向张拉力T与空间弹性支承刚度K的非线性参数模型。采用延伸量测试校验了该方法的有效性。研究表明:该方法准确、快捷,便于工程应用,能有效提高箱梁腹板竖向预应力的施工质量。The phenomenon of web diagonal cracks caused by excessive loss of vertical prestressing is particularly universal. In or- der to effectively test the tension value of vertical prestressed reinforcement, the exposed section of vertical prestressed reinforce- ment was analyzed. Space elastic support model was simulated for the supporting conditions of vertical prestressed reinforcement anchoring parts. When vertical prestressed tension changes, space elastic supporting stiffness and the vibration frequency will change accordingly. These changes can reflect the value of tensile force. Based on model test data, the nonlinear relationship of finishing rolling rebar between tensile force T and the space plane elastic support model K was established. Extension test was used to validate the proposed method. Results show that this method is accurate, fast and convenient for engineering applica- tions, and can effectively improve the construction quality of vertical finishing rolling rebar at box girder webs.

关 键 词：桥梁工程 竖向预应力筋 检测 空间弹性支承模型 精轧螺纹钢筋 模型试验 

分 类 号：U448.213[建筑科学—桥梁与隧道工程] U441[交通运输工程—道路与铁道工程]