As an important means of temporary support, anchor rods are known as "life anchors" in roadway construction, and the quality of their laying is of paramount importance due to the strict requirements for sedimentation control during the construction of underground structures. At present, the construction quality control of anchor support structures is based on destructive pull-out tests, the evaluation index of which is the anchor bearing capacity, which cannot characterise the good or bad construction work and at the same time can cause disturbance to the structure and accelerate deterioration. The elastic wave method of non-destructive testing of anchor rods is a highly promising alternative to destructive testing as an advanced means of verifying the quality of anchor construction at both the anchor rod length and anchorage compactness levels. The failure to popularise the technique is due to the complexity of the wave velocity calibration method, the low repeatability of data collection and the high reliance on experience in data analysis. In this paper, with the aid of finite element analysis and curve fitting, two aspects of improving detection accuracy are investigated in terms of optimising the wave speed calibration method and improving the data acquisition equipment, and the existing research results have been demonstrated in model tests. In this paper, two aspects of wave velocity calibration method optimisation and data acquisition equipment improvement are investigated, and with the help of finite element analysis and curve fitting, the gateway to improving detection accuracy is moved forward. After the finite element simulation analysis and solid model demonstration, the accuracy of the anchor rod non-destructive testing has been significantly improved, and the accuracy of the wave velocity theory formula has reached the application level.
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