Rock mass quality classification is an interesting and formidable issue in the study of rock mechanics

and it plays a very important role in the hydropower engineering construction. With the study of many classification methods

the engineers desire higher regalements for the expression of rock classification. Traditional ways cannot meet the demand of spatial analysis already

and the visualization of rock mass quality classification will be very necessary. Firstly

with a new data structure

3-D strata model is reconstructed using NURBS tool. Then

according to the classification results

the corresponding 3-D classification model can be generated by set operation algorithms of space pattern. The theory is applied to rock mass quality evaluation of Jinping first-level hydropower engineering successfully

and a series of visual analyses correlating with engineering design are also operated. This study acquires very good effects in the practical application.