The Research For Surrounding Rock Mass Mass Classification Of Site Area Weak Rock Mass In Danba Hydropower Station

The exposed bedrock mass of Dan ba site area is Smx4 rock mass group (Smx4) of the fourth generation of MAO county。The lithology is mainly two Mica schist。Rock mass lithology is softer. Reasonable evaluation of engineering rock mass quality of its available degree judge, and plant layout, the design of the structure has important scientific significance. On the base of the agent CPD1 underground workshop deformation damage characteristics of danger, and stable state of weak rock mass, Papers makes the classification of surrounding rock masss research, and gives the reasonable classification of surrounding rock masss DBF system, as well as the appropriate method of rock mass type.Firstly, give by some load test site district two Mica schist rock mass uniaxial compressive strength. Through analysis of rock mass creep test, study the two Mica schist rock mass mechanics properties for establishing a time effect of weak rock mass mechanics index and surrounding rock mass foundation class relations.On the basis of field investigation, use Q system, RMR classification, HC classification, BQ classification four of common surrounding rock masss categorization, soft rock mass agent for classification of surrounding rock masss, through danger with actual rock mass type (based on the deformation damage characteristics and stability evaluation expert evaluation results) contrast analysis, find out of various methods in the soft rock mass tunnel existing in the classification of surrounding rock masss the advantages and disadvantages.Then analyses the various kinds of soft rock mass influences on stability and deformation damage characteristic, extracts the key indicator; And given the large deformation of soft rock mass with rock mass type of the corresponding relation between potential. Finally the common method of classification of surrounding rock masss are analyzed, the common classification system is revised, establish Dan ba soft rock mass surrounding rock mass classification system DBF; Then using relevance, consistency, applicability verification, finally combining site support measures, set up the research and analysis of different rock mass type supporting system.