摘要
介绍了采用钢弦式表面应变传感器、千分表和钢筋应力传感器量测隧道型钢拱架应力的方法及其优缺点;采用力学计算和数值模拟的方法,对比分析了钢弦式表面应变传感器和钢筋应力传感器量测隧道型钢拱架变形(或应力)存在的差异。研究结果表明:千分表法量测的型钢拱架变形存在一定的误差,因为量测的是圆弧拱弦的变形,而且探头的安装比较烦琐,不便测试,对施工的干扰较大;钢筋应力传感器量测的型钢拱架变形并不是型钢拱架本身受力的变形,因为钢筋应力计焊接后对所测部位的型钢拱架起到了加固作用,力学计算结果表明:其所量测的变形值是型钢钢架和钢筋应力计两者共同受力产生的变形值。有限元模拟结果表明:由于钢筋应力计的存在,增加了型钢拱架的截面面积,使得型钢拱架在焊有钢筋应力计部位的轴力减小了20%左右;弯矩减小了10%～20%左右;钢弦式表面应变传感器能够比较真实地反映钢架的应变和受力,具有现场操作快捷、长距离测试方便、精度和灵敏度高、长期稳定性好等特点。推荐采用钢弦式表面应变计量测型钢拱架应力。
The methods of steel string-type surface strain sensor,dial gauge and steel stress sensor for measuring tunnel steel arch stress and their advantages and disadvantages were introduced. Through mechanical calculation and numerical simulation, comparative analysis of the difference between the surface strain sensor and steel strain gauge measuring the tunnel steel arch strain （stress） was conducted. The results show that the method of dial gauge is likely to make errors, because the measurement is on the arch chord deformation and the installation of the probe is rel- atively cumbersome and inconvenient for test with relatively large construction disturbance; the deformation value of measurement by the method of steel stress sensor is not that of the steel arch itself, because the steel stress sensor reinforces the welding parts of steel arch and the mechanical calculation results show that the deformation value of their measurement is that of the steel arch and steel stress sensor jointly. Finite element simulation results show that due to the presence of steel stress sensor, the cross-sectional area of steel arch is increased, making the axial force of the steel arch in the weld parts decrease by about 20%; moment decreases by 10%-20%. Steel string-type surface strain sensor is able to reflect the strain and force of steel arch factually, which has many advantages, such as simple field operation, convenient for long distance test,high precision and sensitivity, longtime stability and so on. Therefore, we recommend using steel string-type surface strain sensor to measure the stress of steel arch. 3 tabs, 14 figs, 9 refs.
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2013年第4期47-53,共7页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金项目(51278063)
973计划项目(2013CB036003)
国家科技支撑计划项目(2011BAE27B04)
交通运输部西部交通建设科技项目(2008 318 000 59)
关键词
隧道工程
型钢拱架
钢弦式表面应变传感器
钢筋应力传感器
应力
量测
tunnel engineering
steel arch
steel string-type surface strain sensor
steel stress sen-sor
stress
measurement
