分布式光纤传感技术在蜗壳模型试验中的应用

分布式光纤传感器与传统应变片和光纤光栅传感器相比,具有分布式测量的显著特点,成为传感器领域的研究热点。随着技术的进步,基于瑞利散射的光频域反射技术(OFDR)得到了迅速的发展。该文介绍了OFDR的测量原理,并将分布式光纤传感器应用于蜗壳模型试验中。为检验蜗壳充水后的变形规律,检查蜗壳和混凝土的整体安全性和设计的合理性,对蜗壳试验过程中外围混凝土应变进行监测。通过分布式光纤传感器在每级水压加载下产生的应变,获得蜗壳模型外部变形以及裂缝发展的情况。实验结果表明,分布式光纤传感器能够真实地反应结构物的应变分布,及时准确地监测蜗壳模型在加压作用下混凝土变形及开裂情况,对结构的损伤进行识别。

Application of Distributed Optical Fiber Sensing Technology in Model Test of Spiral Case

Compared with the traditional strain gage and fiber grating sensor, the distributed optical fiber sensor has the remarkable characteristic of distributed measurement and has become the research hotspot in the field of sensors. With the progress of technology, the optical frequency domain reflectometry (OFDR) technology based on Rayleigh scattering has been developed rapidly. The measuring principle of OFDR is introduced and the distributed optical fiber sensor is applied to the spiral case model test. In order to test the deformation law of the spiral case after water filling, the overall safety and design rationality of the spiral case and concrete have been checked, and the external concrete strain during the test has been monitored. Through the strain generated by the distributed optical fiber sensor under each level of water pressure loading, the external deformation of the spiral case model and the development of cracks are obtained. The experimental results show that the distributed optical fiber sensor can truly reflect the strain distribution of the structure, timely and accurately monitor the deformation and cracking of the spiral case model under the action of pressure, and identify the damage of the structure.