提出一种利用光纤布拉格光栅(FBG)测试双壁模型管桩桩身轴力的方法,探讨模型管桩应变变化与光纤光栅中心波长稳定性和漂移的关系。FBG传感器封装在模型管桩外管加工槽体内,模型管桩内管采取直接粘贴光纤光栅的方法,将应变片分别粘贴在模型管桩内、外管光纤光栅同一位置。对模型管桩施加竖向压力后产生的应变进行测试,并将FBG传感器及应变片的测试结果与理论公式进行对比分析,发现两者存在误差,但在测试要求范围内。外管施加5 kN竖向荷载时,光纤光栅测得的最大应变为59.2 με,相对误差为4.9%;内管施加5 kN竖向荷载时,光纤光栅测得的最大应变为122.3 με,相对误差为7.2%,均满足工程测试要求。

Based on the principle of the fiber Bragg grating, a new type of fiber-optic pressure sensor for axial force measurement of transformer winding is designed, which is designed with the structure of bending plate beam, the optimization of the packaging process, and material of the sensor. Through the calibration experiment to calibrate the sensor, the field test results of the Taikai transformer factory show that the sensitivity of the sensor is 0.133 pm/kPa and the repeatability error is 2.7% FS. The data of the fiber-optic pressure sensor in different positions maintain consistent and repeatable, which can meet the requirement of the real-time monitoring of the axial force of transformer winding.

引入光纤光栅传感器，并结合螺纹管压弯扭分离测量理论，实现对螺纹管所受压力、弯矩和扭矩的测量.由测量结果可知，光纤光栅传感器测得压力与驱动电机上压力传感器测得压力基本相符，两者测得压力的差值为-11.4~15.5 N；光纤光栅传感器测得弯矩与理论值基本一致，两者之间的差值为-0.54 ~0.46 N·m；光纤光栅传感器测得扭矩与驱动电机上扭矩传感器测得扭矩基本相符，两者测得扭矩的差值为-0.54 ~0.87 N·m.测量结果验证了光纤光栅传感器对螺纹管力学参数测量的可行性，为螺纹管的力学参数测量提供了一种新方法.