Study on Correlation between BQ Method,Q Value Method and RMR Method of Railway Tunnel
Research purposes:Surrounding rock classification is a key parameter to be determined in the design and construction of railway tunnels.With the in-depth implementation of China's railway"going out"strategy,it is often difficult for Chinese design engineers and international consultants to reach a consensus on the selection and application of tunnel surrounding rock classification methods,thus affecting the smooth development of overseas projects.In order to study the correlation between Chinese standard BQ method and the international mainstream Q value method and RMR method,the three surrounding rock classification methods,BQ method,Q value method and RMR method,were summarized and compared,and a number of representative railway tunnels at home and abroad were selected to use the above three methods to classify the surrounding rock on the tunnel face of the same chainage,and the classification results were compared and analyzed in combination with other literature research results.Research conclusions:(1)Q value method and RMR method both have advantages and disadvantages in practical engineering applications,and the determination of site surrounding rock grade should be combined with the Chinese standard BQ method to reach a conclusion.(2)The relationship between[BQ]value and Q value conforms to exponential function,the relationship between[BQ]value and RMR value conforms to linear relationship,and the relationship between Q value and RMR value conforms to logarithmic function.(3)In terms of the difference of research results on the relationship between BQ method,Q value method and RMR method in different literatures,the relationship between Q value and RMR value is the smallest and most widely used,followed by the relationship between[BQ]value and RMR value,and the relationship between[BQ]value and Q value is the largest.(4)This paper establishes a corresponding relation table between the Chinese standard BQ method,the international Q value method and the RMR method for the classification of surrounding rock grades.In the case that the BQ method cannot be applied to the classification of surrounding rock grades,the table can help Chinese design engineers to understand and select the surrounding rock supporting system.The research results will be conducive to the mutual learning and integration between BQ method,international Q value method and RMR method.It has certain guiding significance for overseas tunnel engineering design and construction.
surrounding rock classificationBQ methodQ value methodRMR methodcorrelation
万方数据
维普
