Abstract
Recently many dams are constructed on soft rocks due to increasing demands of flood control and city water supply.
Conventional rock classification cannot be applied to soft rocks in a direct way since the spacing and the condition of discontinuities are less important factors than the hardness in the rock classification.
The authors have developed the Pendulum Rebound Tester which can evaluate the hardness of soft rocks quantitatively. After a comprehensive study using the Pendulum Rebound Tester, it is found that the Tester is well utilized in the soft rock classification.
