Dynamic displacement monitoring of flexural structures with distributed long-gage macro-strain sensors
Dynamic displacement monitoring of flexural structures with distributed long-gage macro-strain sensors
复制标题
使用分布式长规格宏应变传感器监测弯曲结构的动态位移
DOI：
10.1177/1687814017698885
复制
发表时间：
2017-04-17
影响因子：
2.1
通讯作者：
Tang, Yongsheng
中科院分区：
文献类型：
--
作者：
Wang, Tao;Tang, Yongsheng
提出了一种监测受弯结构动位移的新方法。该方法首先利用长径光纤光栅传感器获得了分布宏观应变。然后，应用共轭梁理论计算位移。为了验证该方法，安装了所提出的传感器的悬臂梁受到自由振动。该方法与传统位移传感器的测量结果吻合较好，前三个峰值的误差均小于5%。建立了考虑卡车荷载的简支多梁桥有限元模型。结果表明，该方法在所有情况下的最大位移误差均小于3%，能较准确地评估动位移。最后，用随机动力荷载作用下的简支梁模型对该方法进行了验证。但是，传感器的量规长度对测量结果有一定的影响。为确保精确测量，传感器量规长度应限制在小于光束长度的1/20。考虑到光纤传感的其他优点，该方法在长期结构健康监测领域具有广阔的应用前景。
A new method is proposed to monitor dynamic displacement for flexural structures especially. In this method, the distributed macro-strain is first obtained using long-gage fiber Bragg grating sensors. Then, the conjugated beam theory is applied to calculate the displacement. To verify the method, a cantilever beam, installed with the proposed sensors, is subjected to free vibrations. The results from the proposed method agree well with those measured by the traditional displacement transducer as the error for the first three peak values is less than 5%. A finite element model of a simply supported multi-girder bridge is also simulated with a truck load. The results show that the proposed method can evaluate dynamic displacement accurately as the error for the maximum displacement is less than 3% in all the cases. Finally, the method is verified using simply supported beam models subjected to random dynamic loads. However, the sensor gage length shows some influence on the results. To ensure exact measurements, the sensor gage length should be limited to be smaller than 1/20 of the beam length. Considering other advantages of fiber optic sensing, the proposed method shows promise in the field of long-term structural health monitoring.