Structure Characteristics of Inlaid Cataclastic in Situ of Basalts with Chloritized Joints

摘要

Basalts with chloritized joints were distributed in dam foundation and two banks of low altitude in Jin’anqiao hydroelectric power station, and these special basalts were named basalts with joints chloritization. In studying area, basalts were cutting severely by dense chloritized joints. In the light of existing Code for Water Resources and Hydropower Engineering Geological Investigation(GB50287-99,China), types of rock mass structure should be inlaid cataclastic structure or cataclastic hstructure, and types of rock mass quality should be grade Ⅳ or grade Ⅲ2, but in situ condition, basalts closely locked. Through field investigation and analysis, found out these were new special structure rock masses named inlaid cataclastic structure in situ. These cataclastic structure rock masses were discreted in situ, and differentiated with fracture zone by tectonic process or displacement. The inlaid cataclastic structure rock mass in situ had some characteristics: with quasi–integrality; low permeability, high rock mass wave velocity, high deformation modulus. Based on these characteristics, put forward the rock mass structure classification scheme of these new inlaid cataclastic rock mass in situ.