STUDY ON ASSESSMENT OF ROCK MASS QUALITY AT DAM FOUNDATION OF GEHEYAN HYDROPOWER PROJECT ON QINGJIANG RIVER

The basic quality of rock mass at the dam foundation of Geheyan hydropower pro ject is determined by using qualitative and quantitative methods assighed in Criteria for Classification of Engineering Rock Mass and according to the roc k hardness and intact degree. Then a quality classification of the rock mass at the dam foudation is made on the basis of groundwater, ground stress,and the si tuation of soft and weaken structural planes, and the modified assessment resu lts of the rock mass quality. Considering the engineering practice, such as inte rlayer shear plane, karst situation,etc,the assessment result of engineering roc k mass system at the dam site is obtained.