Yuan Qiang, Chai Jing, Ren Yiwei, Liu Yongliang
State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China.
College of Energy Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
Sensors (Basel). 2020 Dec 16;20(24):7215. doi: 10.3390/s20247215.
The evolution of overburden deformation is crucial for safety and environmental efficiency and its monitoring is becoming a key scientific issue. The use of an optical fiber sensor (OFS) for mining engineering is now receiving praise by virtue of its distinct abilities of distribution, high accuracy, and anti-interference measurement. Nevertheless, the dynamic response of OFS monitoring on overburden deformation still needs to be characterized in detail. This paper analyzed the characterization pattern of overburden deformation based on distributed optical fiber sensing (DOFS) by means of an analogue model test. Then, we discuss the influence of rules of optical fiber embedding on a model test in a numerical simulation. The results show that the DOFS monitoring demonstrates the time-space evolution of overburden deformation and the development of three horizontal areas and three vertical zones. A standardization DOFS characterization model is proposed to expound the characterization mechanism of the overburden structure zoning process; the influence of optical fiber embedding on rock displacement in the model test is revealed, and it is found that the displacement error will increase sharply when the fiber diameter is larger than 2 mm. These findings could provide an effective solution for a monitoring method in intelligent mining from the perspective of a theoretical basis and technological system.
覆岩变形演化对安全和环境效率至关重要,其监测正成为一个关键科学问题。光纤传感器(OFS)因其独特的分布式、高精度和抗干扰测量能力,在采矿工程中的应用正受到赞誉。然而,OFS监测覆岩变形的动态响应仍需详细表征。本文通过模拟模型试验,分析了基于分布式光纤传感(DOFS)的覆岩变形表征模式。然后,在数值模拟中讨论了光纤埋设规则对模型试验的影响。结果表明,DOFS监测揭示了覆岩变形的时空演化以及三个水平区域和三个垂直带的发展。提出了一个标准化的DOFS表征模型来阐述覆岩结构分区过程的表征机制;揭示了光纤埋设对模型试验中岩石位移的影响,发现当光纤直径大于2mm时,位移误差将急剧增加。这些发现可以从理论基础和技术系统的角度为智能采矿中的监测方法提供有效的解决方案。