基于光纤光栅传感器技术的边坡位移监测及稳定性分析

发布时间：2018-04-23 02:39

本文选题：应变 + 差分算法　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：边坡的失稳会导致建筑物的破坏,交通设施瘫痪,造成人员伤亡和经济损失,是相当严重的全球性自然灾害。为了尽可能地减小边坡失稳造成的危害,许多学者开始对边坡安全性实时监测、预报展开研究,取得了很好的成果。伴随光纤传感技术的迅猛发展,光纤光栅传感器技术开始被运用于边坡的稳定性监测。本文采用ABAQUS有限元软件分析了表面粘贴式光纤光栅传感器应变传递率的影响因素,得到了基体层和粘结层的厚度、弹性模量、泊松比,以及光栅长度对光纤光栅的应变传递率的影响。因此,为了消除基体材料和减小粘结层厚度的影响,本文选取裸光栅来进行分析。通过在测斜管表面合理地布设光纤光栅传感器来实现温度的自补偿。采用数值模拟与室内试验对中心差分计算位移的正确性进行了验证,并结合外推法提高了位移计算精度;同时对经典的位移积分算法进行了改进,发现分段位移叠加法的计算精度高于经典的位移积分算法。根据极限平衡理论得到了计算边坡稳定系数的积分求解方法,并且结合Geo Studio-slope/w和ABAQUS分析了影响边坡稳定性的各种因素,验证了积分算法的正确性。同时采用数值模拟对基于位移信息的边坡稳定性计算模型进行了数值分析。最后以测斜管为载体,结合位移计算方法,成功地将光纤光栅传感器应用边坡模型试验中,将监测到的位移与通过PIV技术获取的土体变形进行了对比分析;同时,结合位移增量目标函数搜索边坡的潜在滑裂面位置,进而对边坡稳定性进行了分析,其结果与Geo Studio-slope/w确定的边坡安全性情况相当。验证了基于光纤光栅测斜仪的边坡健康监测及安全性分析算法的可行性。
[Abstract]:Slope instability will lead to the destruction of buildings, traffic facilities paralysis, resulting in casualties and economic losses, is a serious global natural disaster. In order to reduce the damage caused by slope instability as much as possible, many scholars began to study the real-time monitoring and prediction of slope safety, and achieved good results. With the rapid development of fiber optic sensing technology, fiber grating sensor technology has been applied to slope stability monitoring. In this paper, ABAQUS finite element software is used to analyze the factors influencing the strain transfer rate of the surface bonded fiber grating sensor. The thickness, elastic modulus and Poisson's ratio of the matrix layer and the adhesive layer are obtained. And the effect of grating length on the strain transfer rate of fiber grating. Therefore, in order to eliminate the influence of matrix material and reduce the thickness of bonding layer, the bare grating is selected for analysis. The self-compensation of temperature is realized by arranging the fiber Bragg grating sensors reasonably on the surface of the inclined tube. The accuracy of central difference calculation is verified by numerical simulation and laboratory test, and the accuracy of displacement calculation is improved by extrapolation, and the classical displacement integral algorithm is improved. It is found that the accuracy of the piecewise displacement superposition method is higher than that of the classical displacement integral algorithm. According to the limit equilibrium theory, an integral method for calculating the slope stability coefficient is obtained, and various factors affecting the slope stability are analyzed with Geo Studio-slope/w and ABAQUS to verify the correctness of the integral algorithm. At the same time, numerical simulation is used to analyze the slope stability model based on displacement information. Finally, with the inclined tube as the carrier and the displacement calculation method, the measured displacement and the soil deformation obtained by PIV technology are compared and analyzed successfully in the slope model test of fiber Bragg grating sensor. Combined with the displacement increment objective function, the potential slip surface location of the slope is searched, and the slope stability is analyzed. The results are similar to the slope safety determined by Geo Studio-slope/w. The feasibility of slope health monitoring and safety analysis algorithm based on fiber grating inclinometer is verified.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU433

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