| The analysis and evaluation of surrounding rock stability is an eternal theme of underground engineering. Through theoretical analysis, laboratory researches, similar simulations and numerical simulations, this article has systematically done the following: studies the nondestructive detection in the theoretical basis, test methods, wave shape identification and quality evaluation index parameter of anchorage quality of rock bolt, homologous relationship has been established between working load of bolt and the convergence and deformation and displacement of laneway's periphery, forward a new method for real-time detection and evaluation of surrounding rock stability on the basis of the nondestructive detection of working load of bolt, and conducts some small-scale industrial test in the mine. The study achievements which have been obtained are as follows:1. On the basis of the theory of one dimension elastic wave motion, mechanics model of grouted rock bolt vertical vibration is established, and the analytical solution under different supporting conditions is found. These results provide theoretical supports for nondestructive detection of anchorage quality of rock bolt.2. The test and study of the nondestructive detection in anchorage quality of rock bolts has been conducted in the laboratory, and six parameters of evaluating the anchorage quality of rock bolt have been found: valid bounding length, ratio of amplitude, attenuation coefficient, primary frequency, ratio of frequency and dynamic stiffness. The analysis of response signal in the end of the rock bolt is helpful to accurately measure valid grout length, to judge consolidation situation between the anchorage and the surrounding rocks, and to evaluate anchorage quality and ultimate bearing capacity of rock bolt.3. The scientific concept of "consolidation wave speed" has been put forward. By some simulation tests, the upper and lower limit value of consolidation wave speed has been decided, and the conclusion that "the relationship between the bond strength and consolidating wave speed is negative exponential function" has been concluded. According to the consolidating wave speed in the anchorage structure, the rock bolt's ultimate bearing capacity can be predicted, and the anchorage quality can be evaluated.4. Through the theoretical analysis and tests studies, the conclusion that "the relationship between working load of rock bolts and the main frequency of the response signal of rock bolt end is power exponent function" has been reached. A new method that " evaluate surrounding rock stability based on the nondestructive detection of the working load of bolt" has been raised. Through the nondestructive detection of rock bolt's working load, the real-time evaluation of the supporting structure and the surrounding rock stability has been made. The field industrial test results proved the above-mentioned conclusion.5. By the similar model loading test, the relationship between working load of rock bolt and the deformation of the surrounding rocks has been found. This achievement helps to get a good method to evaluate the stability of anchorage's structure and the surrounding rock by detecting the working bearing of bolts.6. Based on lab model, finite element model is made under ANSYS. Numerical simulation results agree well with the lab test. This also verifies above mentioned law.7. Wavelet analysis, multi-differentiate analysis, shelf-adaptive filter method, and some other signal processing methods have been used to analyze the testing signal. The error analysis shows that the above-mentioned methods are consistent with each other.8. MATLAB program for analyzing test signal, which can evaluate the anchorage quality of rock bolts, has been developed. The program helps to increase the analysis precision.9. The field test results show that it is feasible to use the method to measure the anchorage quality of rock bolts and its working load and then to make real-time evaluation of the stability of the surrounding rocks.
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