Structure and Application of SHF Classification Method for Surrounding Rock of Sandy Dolomite Tunnel
Dong Jiaxing
Gong Xinyue
Mi Jian
Fan Kaiyuan
Yang Runxue
Zhao Yongchuan
Mu Hongyuan
Zhou Lunshun
Abstract：Sandy dolomite is widely distributed in the southwest of China.When tunnels are built in this stratum,geological disasters such as face collapse,water inrush and sand gushing often occur.Therefore,the problem of sandy dolomite faced in the construction of water diversion project in central Yunnan has attracted much attention.The sanding grade and groundwater conditions are the key factors to control the failure mode and stability of the surrounding rock of the sanded dolomite tunnel.However,these factors are often not fully considered in the traditional surrounding rock classification methods,such as the rock strength is not considered in the Q system,the ground stress is not considered in the RMR method,and the joint state and roughness of the sandy dolomite are not considered in the BQ method.Totally,these classification methods do not take into account the influence of sanding grade.In order to make the surrounding rock classification results of the sandy dolomite tunnel more accurate and faster,it is necessary to build a classification method suitable for the sandy dolomite tunnel.Based on the water diversion project in central Yunnan under construction,we analyze the applicability of traditional methods such as Q method,RMR method,RMi method,GSI method and BQ method in sandy dolomite tunnel.Secondly,combined with the engineering characteristics of sandy dolomite and the external environmental factors,the surrounding rock classification system SHF with the evaluation indexes of sanding grade,structural plane state,groundwater,main structural plane state and ground stress is constructed,and the SHF classification method is verified and applied by selected typical tunnel sections of the project.The established classification method SHF for surrounding rock of sandy dolomite tunnel is prone to operate and highly consistent with the actual situation of the project.The research can provide a theoretical basis for the design and construction of sanded dolomite tunnel support.
Keywords：sandy dolomite stratumSHF method for surrounding rock mass classificationSanding gradeunderground waterwater diversion project in Central Yunnan
Publication Date：2024-08-15
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：13( 2813-2825 )