锚杆无损检测反射信号分形分析及其应用研究

为了避免锚杆无损检测过程中反射信号特征点难以识别的问题，将分形维数中的盒维数引入到锚杆无损检测反射信号的分析之中。为研究锚杆极限承载力与盒维数的关系，通过设置干沙填充的缺陷段、制作不同配比的锚固剂分别从锚固缺陷程度和锚固剂性质两个角度来进行研究。在古交东曲矿井下实地进行了锚杆反射信号的采集并在分析完成后进行了拉拔检测。结果表明：锚杆中的缺陷数目越多，极限承载力越小，响应曲线盒维数越高；锚固剂性质随含砂率增高而改变，极限承载力先增高后降低，响应曲线盒维数增大；在矿区同段巷道内（锚固剂性质相同），响应曲线盒维数越大，工作荷载越大，锚固极限承载力则呈现变小的趋势。

Research on fractal analysis and application of reflected signal in non-destructive testing of bolt

In order to avoid the problem that the characteristic points of the reflected signal are difficult to identify in the process of bolt nondestructive testing, the box dimension in the fractal dimension is introduced into the analysis of the reflected signal of the bolt nondestructive testing. In order to study the relationship between the ultimate bearing capacity of the anchor bolt and the box dimension, the research was carried out from two angles of anchoring defect degree and anchoring agent properties by setting the defect section filled with dry sand and making anchoring agents with different proportions. The reflection signal of the anchor rod was collected on the ground under the Gujiao Dongqu Mine, and the drawing test was carried out after the analysis was completed. The results show that: the more defects in the bolt, the smaller the ultimate bearing capacity, and the higher the response curve box dimension; the properties of anchoring agents change with the increase in sand content, the ultimate bearing capacity first increases and then decreases, the response curve box dimension Increase; In the same roadway in the mining area, the larger the box dimension of the response curve, the greater the working load, and the ultimate bearing capacity of anchoring tends to decrease.