Engineering Rock Mass Classification Of Shuangjiangkou Hydroelectric Station

This article takes the statistics and analysis of the field material as base, usesthe idea combining with qualitative and quantitative analysis, analyses theapplicability of normal rock mass classification methods in SHUANGJIANGKOUhydroelectric station, then finds the problems of the methods and modifies them inSHUANGJIANGKOU hydroelectric station. At last, creates the rock massclassification systems which are suitable for SHUANGJIANGKOU hydroelectricstation. The main research contents:(1) This article preliminarily classifies rock mass of SPD9 which takes fieldmaterial as base and uses qualitative method, BQ, HC, RMR and Q system fivemethods, and classifies rock mass of high rock engineering slops (including damabutment slope, intake and outtake slope and nature slope,)which uses qualitativemethod, BQ, HC, RMR and CSMR five methods.(2) It analyses the preliminary result of SPD9 which includes correlation,coincidence rate, consistence and the difference of rock mass classification, andcombines the consideration factor of normal classification methods which includesbasic and modified factors, then generalizes the two problems of BQ,HC,RMR and Qsystem in SHUANGJIANGKOU hydroelectric station, which include theconsideration of high field stress and rock burst, and the drawback of point system ofthem.①The consideration of high field stress and rock burst: RMR doesn't considerthe high field stress and rock burst; BQ gives the varying points of the coefficient ofhigh field stress—K3, but it doesn't consider the rock burst; HC reduces the rank ofrock mass according to the ratio of strength and stress—S; Q system considers thehigh field stress and rock burst, but doesn't contact the intensity of rock burst withSRF.②The problems of point system: BQ is too sensitive for compression strength ofrock to be suitable for the surrounding rock mass classification ofSHUANGJIANGKOU hydroelectric station; the R1, R2, R3 take sectional pointwhich can cause the point rapid change, the consideration of direction of structuralplane is too easy and fuzzy; the description of Jr and Ja in Q system is different with hydroelectricity industry.(3) It puts forward the detailed programmes to modify the problems in thsurrounding rock mass classification of SHUANGJIANGKOU hydroelectric station.①It uniforms the description of Q system and HC, leads the rock burst intensit(?)in Q-system and modifies the SRF, then create the SJKQ-system.②It puts forward the coefficient of high field stress—K in RMR, leads the roclpressure burst intensity gives continuous points to R1, R2, R3, and modifies th(?)point of structural plane, then create the SJKRMR.③It abandons the subject which reduces the rank of rock mass according to th(?)ratio of strength and stress—S, leads the rock pressure burst intensity and th(?)coefficient of high field stress—K, then create the SJKHC.(4) Considering the practical features of rockmass structure of engineeringslopes in the research area, this article modifies theλ(the coefficient of joincondition) and F3 (the adjust value of dip angle between the joint and slope), the(?)creates the SJKCSMR method. It classifies the slope rockmass of dam abutmenslope, intake and outtake slope, nature slope, at last, puts forward the slope ratiosand evaluates the stability of engineering slope initiatively.(5) It creates systems of engineering rock mass classification. The surroundingrock mass classification system which considers the SJKHC as chief methodSJKRMR and SJKQ-system as supplementary method, the slope rock massclassification system considers the SJKCSMR and SJKHC as chief method, BQ andSJKRMR as supplementary method.(6) It applies and examines the surrounding rock mass classification system inSPD10. The article thinks that the applicability of the system is better inSHUANGJIANGKOU hydroelectric station which has high field stress and it can beused for the engineering which has the same condition of engineering geology.