FBG 相似材料传感器埋入模型内部实验研究

针对模型实验内部关键点的应变测量,设计并制作了光栅-相似材料传感器,与传统的应变砖法中,将光栅粘贴在立方体试件表面相比,该文将光栅埋入相似材料立方体试件内部,以消除边界效应的影响。通过对比实验,研究去涂覆层光栅在相似材料中的布设工艺,为验证所设计传感器应用于模型实验内部应变测量的可靠性,基于圣维南定理,将传感器埋入一边长是其3倍大的相似材料试件中心,以此在模拟实验中有围压的条件及消除边界效应的影响,实验结果验证了测量结果的可靠性。

Experimental Study on Embedded Model of FBG similar Material Sensor

A grating similar material sensor has been designed and fabricated for the strain measurement of the key points in the model experiment interior. Different from the conventional brick strain method of which the grating is pasted on the surface of the cube specimens, the grating used in this work is embedded into the similar material cube specimens in order to eliminate the influence of boundary effect. Through the contrast experiment, the layout process of the decoated grating in the similar material is studied. In order to verify the reliability of the sensor used in the internal strain measurement experiment, based on Saint Venant theorem, the sensor is embedded into the center of the similar material specimen with the side length of 3 times larger over the sensor to simulate the conditions of the actual experiment with the confining pressure and eliminate the boundary effect. The experimental results verify the reliability of the measurement results.