针对大跨度空间索结构施工及运营阶段的索力监测难题, 基于光纤光栅应变敏感的特性, 利用“预应力原理”与凹槽封装技术,该文研制了一种内嵌封装大量程光纤光栅传感器的智能拉索, 解决了光纤光栅传感器工程应用易断裂及监测量程不足的缺陷。在此基础上对其进行张拉试验, 验证智能拉索的主要传感性能指标。试验结果表明, 光纤光栅传感器监测灵敏度约为0.002 66 nm/kN, 线性度误差≤2.86%, 迟滞误差≤1.53%, 重复性误差≤2.40%, 总精度误差≤4.03%, 监测量程可达到拉索极限承载力的80%。采用该技术, 利用光纤光栅传感器对某体育场馆索网结构的施工张拉进行实时监测, 并将光纤光栅传感器监测荷载与千斤顶张拉荷载进行对比, 索体张拉完成后两者误差仅为2.95%。该技术实现了拉索全生命周期、高精度的索力监测。

Aiming at the difficulty of cable force monitoring in the construction and operation stages of large-span spatial cable structures, based on the strain-sensitive characteristics of fiber grating, an intelligent cable embedded with large range of fiber grating sensors is developed by using the "prestress principle" and groove packaging technology, which solves the defects of easy fracture and insufficient monitoring range of fiber Bragg grating sensors in engineering applications. On this basis, the main sensing performance indexes of the intelligent cable are verified by the tensioning test. The results show that the monitoring sensitivity of the fiber grating sensor is about 0.002 66 nm/kN and the linearity error is ≤2.86%, the hysteresis error is ≤1.53%, the repeatability error is ≤2.40%, the total accuracy is ≤4.03%, and the monitoring range can reach 80% of the ultimate bearing capacity of the cable. By using this technology, the construction tension of the cable network structure of a sports stadium is monitored in real-time by using fiber Bragg grating sensor, and the monitoring load of fiber Bragg grating sensor is compared with the tension load of the jack, and the error between the two is only 2.95% after the cable tension is completed. This technology enables high precision cable force monitoring through the full life cycle of the cable.