Deformability study of Gezhouba dam foundation rocks

This paper summarizes the research work done for the study of the deformability of foundation rocks at the Gezhouba Hydraulic Engineering Project on the Yangtze River, China. A total of 109 in-situ deformation tests in 4 kinds of rock have been conducted, using various testing methods. The test results are analyzed to clarify factors influencing the values of modulus of deformation. The dependence of axial strain (or displacement) on the stress state has been investigated and the way of assigning deformability parameters for calculation is discussed. Finally, some suggestions for improving the rock deformability study of future major hydraulic engineering projects are made.