关键词: 柱状节理, 各向异性, 原位试验, 数值试验, 白鹤滩水电站

Abstract: During the development of hydropower stations in Southwest China, more and more attentions have been paid to the engineering mechanical properties of columnar joints rock mass. As dam foundation of Baihetan Hydropower Station is composed of columnar joints basalt, of which the magnitude of RQD is widely lower and integrity is poor; and the mechanical indices such as deformation modulus, is relatively lower. Meanwhile, the rock mass significantly shows anisotropy. Therefore, it has imposed a certain impacts on the deformation of arch dam, and the stability of abutment, high slope, and underground rock caverns; it has become one of the key technical issues of Baihetan Hydropower Station. As we know, the researches on columnar joints rock mass and related engineering experiences at home and abroad are few. Therefore, in order to obtain the first-hand observation data reflecting mechanical properties of columnar joints rock mass, we plan to develop the large-scale columnar joints experimental cavity. The geologic origin and characteristics of columnar basalt and the design proposal of experimental cavity are introduced here; the combination of in situ experiment and numerical experiment is discussed. Then anisotropic constitutive is use to simulate the excavation and in-situ experiment and the representation sites are appraised.

Key words: columnar joint, anisotropy, in-situ experiment, numerical test, Baihetan Hydropower Station