Field seepage tests on discontinuity structural rocks in a hydropower project

The permeability characteristics of the structural planes inside rock masses are of importance for the stability of hydropower station projects. In this paper, a large-scale in-situ seepage testing method was proposed and applied to the tests on the gently dipping structural plane (C2 zone) and the steep fault (F14) in the construction field of one hydropower station in China. The in-situ test results were compared with those of both the undisturbed and the reconstituted specimens. The test results indicate that the proposed in-situ testing method can be effectively used to determine the permeability characteristics of structural planes under the natural stresses with a relatively high accuracy. The critical hydraulic gradient of the structural planes is influenced by the natural stress of the surrounding rock mass, which cannot be reflected in the tests on the undisturbed and the reconstituted specimens.

کلیدواژه ها:

In-situ seepage test ، permeability characteristic ، rock discontinuity structural plane