Based on a dam foundation engineering in Fujuan province

single-hole acoustic test

cross-hole acoustic test and seismic wave test were carried out to detect the P-wave velocity of dam foundation rock mass before and after consolidation grouting. The elastic theory was used to calculate dynamic elastic modulus; and the change of deformation parameters before and after consolidation grouting were studied. A modified Hoek-Brown criterion was proposed to calculate the parameters in Hoek-Brown criterion. The results show that the consolidation grouting effect is controlled by the groutability of rock mass and effected by the rock mass structure. The consolidation grouting effects in different directions are different. For strongly weathered rocks

the consolidation grouting effect in vertical direction is better than that in horizontal direction. For medium weathered rocks with gently dipping discontinuous faces

the consolidation grouting effect in horizontal direction is better than that in vertical direction. The functional relationship between the increasing rate of dynamic elastic modulus and the increasing rate of velocity is quadratic. The functional relationship between the increasing rates of m

s (where m is Hoek-Brown parameter

s is parameter related to quality of rock mass) and the increasing rate of velocity for strongly weathered rocks are both linear and for medium weathered rocks are both cubic. It is of important significance for design and construction of grouting.