长江小南海水利枢纽坝基弱风化岩体工程力学性质研究及可利用探讨  

DISCUSSION ON MECHANICAL PROPERTY AND UTILITY OF WEAKLY WEATHERED ROCK MASS FOR ON YANGTZE RIVER XIAONANHAI HYDROPWER PROJECT

作　　者：李维树[1,2] 谭新[1,2] 黄志鹏[1,2] 

机构地区：[1]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010 [2]长江科学院重庆岩基研究中心,重庆400014

出　　处：《岩石力学与工程学报》2008年第A02期3899-3904,共6页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(50639090);水利部岩土力学与工程重点实验室开发基金资助项目(G07-16)

摘　　要：小南海水利枢纽为长江上第三座大Ⅰ型水电工程,坝基为典型的红层软岩,岩体风化层次分明。坝基覆盖层及强弱风化带平均厚约18m,其中弱风化带平均厚约6m,若全部挖除,相当于总开挖深度的1/3,开挖工程量巨大。从坝区大范围岩体波速的分布、工程岩体质量分级、岩体变形特性及强度特性等方面对比研究弱风化岩体与微风化岩体的差别,探讨弱风化岩体作为建基面的可能性。本阶段的试验研究结果说明,弱风化与微风化岩体均为IV级,弱风化岩体的岩石力学参数与微风化岩体差别不大,具备作为建基面的工程力学条件。Xiaonanhai Hydropower Project is the third large grade I hydropower project on Yangtze River. Its rock foundation is composed of typical red beds, which have been weathered and demarcated clearly. The average thickness of the overburden and strongly weathered zone is 18 m, and the average thickness of the weakly weathered zone is about 6m. If all the weakly weathered rock masses are excavated, the excavating depth will be equal to one third of the total one. Obviously, the excavating volume is huge. The wave velocity distribution of rock mass in a large area of dam site, engineering classification of rock mass quality, deformation and strength properties of rock mass are analyzed. The differences between weakly and slightly weathered rock masses are researched, and the probability of using the weakly weathered rock mass as foundation plane is discussed. The experimental results of this stage show that the qualities of weakly and slightly weathered rock mass are grade IV, the mechanical parameters of weakly weathered rock mass approach to those of slightly weathered rock mass, and the weakly weathered rock mass can be used as foundation plane.

关 键 词：岩石力学 长江小南海水利枢纽 岩体质量分级 岩石力学特性 弱风化岩体利用 建基面 

分 类 号：TU45[建筑科学—岩土工程]