Study On Evaluation Of Rock Mass Quality By Comprehensive Geophysical Testing Parameters

In geotechnical engineering design and construction,the quality evaluation and quality classification of rock mass are often performed by a representative parameter,due to the limitations of the evaluation parameters,the quality evaluation and classification of rock mass are also limited.Aiming at these limitations,the methods of quality evaluation and classification for rock mass in the test area were studied using the three parameters of acoustic wave velocity,crack distribution and state,elastic modulus(deformation modulus)of rock mass that obtained from three kinds of fast testing methods of borehole acoustic wave,borehole panoramic imaging and borehole elastic modulus(variable modulus)in the exploration and testing work.In the course of the study,5 research results have been obtained.(1)The intersection of fracture and borehole wall was analyzed in the panoramic image of the borehole image,and on this basis,the information such as fracture occurrence and gap width was extracted.(2)The influence of the number of evaluation parameters in the unknown measure evaluation method on the evaluation accuracy was studied,and gave the number of parameters that guarantee the accuracy of the evaluation in a relatively moderate number,and proposed parameter combination of evaluation model combined with this study.(3)The classification results of three kinds of evaluation methods and the evaluation methods such as GB and RMR were compared,the results showed that the extension element evaluation method had high accuracy.(4)Aiming at the disadvantages of extension primitive evaluation method,the probabilistic fuzzy set theory was used to improve the extension primitive evaluation method in this paper.Evaluate the accuracy of the modified extension element group Evaluation was some increase,especially in the case of low grade rock evaluation results of large deviation level the basic solution,dramatically reducing the case where the deviation is greater than two levels.(5)In order to make the evaluation process fast and accurate,an improved extension element evaluation method was developed on the MATLAB platform in this paper,and the operation process was introduced.At the end of this paper,the improved extension element evaluation method was used to evaluate the rock mass of Sha Tuo power station and achieved good results.