混凝土桥梁振弦传感器应力测试温度影响性分析

摘要

To eliminate the influence of temperature on the stress testing of concrete bridge,the sen-sors buried in concrete,in statically determinate bridge structure and the bridge structure under unre-stricted condition were compared in terms of long-term temperature and stress testing,and the rela-tions between the two are given in-depth study,and the temperature influential factor of strain testing using buried vibrating wire sensors and the modification formulas are proposed.The results of the study indicate that the strain testing carried out under unrestricted condition shows minimal change a-gainst the yearly temperature variation,maintains within the range of (-8~0)×10 -6 and the influen-tial factor basically keeps at -0.3×10-6/℃.However,for the sensors buried in the testing samples and in the statically determinate bridge structure,the strain testing results exhibit substantial change, as the temperature rises,the measured compressive strain from the stress sensors significantly increa-ses,with the maximum value reaching up to - 166 × 10 -6 ,the mean yearly temperature influential factor is -4.3×10-6/℃,which has great influence on the stress testing results of the structure and must be modified.%为消除温度对混凝土桥梁应力测试的影响，对埋入混凝土试件、静定桥梁结构中及自由状态下的传感器进行了温度、应变长期测试，研究两者之间的关系，给出埋入式振弦式传感器测试应变的温度影响性系数。研究结果表明，随全年温度变化，自由状态下的传感器测试应变变化较小，基本在（－8～0）×10－6之间，影响系数基本为－0．3×10－6／℃；埋入试件及静定桥梁结构中传感器测试应变变化较大，随温度升高，应力传感器实测压应变显著增大，最大可达－166×10－6，全年平均温度影响系数为－4．3×10－6／℃，对结构应力测试结果影响较大，应予以修正。