Novel electric nondestructive anchor rod length measuring method and device

Abstract

The invention provides a novel electric nondestructive anchor rod length measuring method and device. The novel electric nondestructive measuring method includes that a measuring hole is drilled when measuring and connected with the anchor rod, a direct-current stabilized power supply, a resistance test instrument and a metal ball probe in sequence, the direct-current stabilized power supply outputs constant direct-current voltage to detect resistance values of loops; the metal ball probe is moved downwardly along the measuring hole to measure the resistance values of the loops secondarily; the rest is done in the same manner till the metal ball probe moves deep to the bottom of the measuring hole; a resistance-depth curve is drawn according to multiple acquired resistance values, and actual embedment length of the anchor rod is judged according to increasing turning points appeared in the resistance-depth curve. In the measuring method, the bottom of the anchor rod can be measured by utilizing direct-current electric fields generated from the a metal anchor rod and resistance change of the loops by adjusting relative position of point electrodes and anchor rod electrodes. The novel electric nondestructive anchor rod length measuring device is simple in overall structure, convenient to operate, and applicable to measurement of the anchor rods in surrounding rocks under poor conditions.

Description

technical field [0001] The invention belongs to the technical field of non-destructive testing of civil engineering, and relates to a method for non-destructive detection of the embedded length of a bolt based on the electrical conductivity of the bolt-surrounding rock system, and in particular to a new electrical method for non-destructive detection of the length of a bolt. The present invention also relates to A detection device used in the detection method. Background technique [0002] Anchor is an important means of underground engineering (tunnels, caverns, etc.) and slope control engineering in the construction of railways, highways, hydropower stations, etc. The length of the bolt embedded in the rock formation or soil layer is the key factor for its maximum effectiveness. Therefore, it is extremely important to quickly and accurately detect the length of the bolt with a huge amount of engineering. However, the bolt has a strong concealment, and it is very difficult...

AI Technical Summary

Problems solved by technology

However, the bolt has a strong concealment, and it is very difficult to effectively detect its length.

[0003] The stress wave non-destructive testing technology commonly used in China has the uncertainty that the bottom reflection signal is likely to weaken or even disappear.

However, the improved methods of processing detection waveforms proposed by frequency adjustment, wavelet analysis, and neural network analysis techniques are not widely applicable at present, and the analysis, processing and interpretation methods for detection data are relatively lagging behind.

Therefore, this detection technology still cannot meet the current extensive bolt detection needs.

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