某大型水电站坝区岩体风化分带定量划分初探

Primary study on quantitative zonation of the weathering degree of rock mass at a large hydro-power station

岩体风化程度的划分对岩体质量的准确分级及建基面的确定具有重要意义。但定性划分岩体风化程度往往受到主观因素的制约,存在评价时的任意性,且不能客观反映岩体风化的本质特征。而选取一些能反映岩体风化特征的指标对岩体进行风化量化分级,则较为准确、客观。论文结合西南某大型电站基本情况,根据国内外的研究成果,选取岩石质量指标(RQD)、裂隙间距(D)、波速比(Bv)、完整性系数(Kv)、岩石单轴抗压强度及2m硐段裂隙数等适合坝区岩体定量风化分带的特征指标,对主要指标进行相关性分析。最后根据选定指标定量划分出坝区岩体风化分带,以期对类似工程有一定的指导意义。

The weathering degree of rock mass is very important to class the rock quality accurately and make certain the dam base surfaces, but the qualitative classification has some randomcity when appraising for being restricted by subjective factors, and cannot reflect the rotten genius character of the rock mass. However, if having a quantitative classification by choosing some indexes that can reflect the characters of the weathering degree of rock mass, that is more impersonality and. nicety. This text selects some characteristic indexes including rock quality designation（RQD）, fracture space（D）, velocity ratio（By）, integrity index（Kv）, uniaxial compressive strength of rock, the joint number per 2m-section in the cave that considers the common fact of the power station in Southwest China and suit for the area of hydro-power station, and basing on the domestic and foreign research results, then analyses the relativity of the major indexes. At last, it compartmentalizes the weathering classification quantitatively by the selected indexes for the rock mass in station area, and expects that it will be instructive for analogous projects.