大岗山水电站辉绿岩脉工程地质特性研究

Study of engineering geological characteristics of diabase dikes of Dagangshan Hydropower Station

大岗山水电站左岸坝基出露的β21辉绿岩脉,具有强度高、较破碎的特性,直接影响到坝基变形和抗滑稳定。介绍了β21辉绿岩脉的基本特征,包括分布范围和规模、产出特征、岩石蚀变特征、接触关系及掩体结构和岩体质量分类。抗变形能力和抗滑稳定分析表明,需要对辉绿岩脉β21采取工程处理措施以满足拱坝建设要求。介绍了具体的工程处理措施,可供同类工程参考。

The diabase dikes β21 outcropped in the left bank of dam foundation of Dagangshan Hydropower Station is characterized as high strength and slightly fracturing,which influences the deformation and anti-sliding stability of dam foundation.The basic features of diabase dikes β21 are introduced,including distribution range and scale,tectonic and alteration characteristics,contacting relation and blindage structure and rock quality classification.The characters of spatial distribution and engineering geology of diabase dikes β21 are described.The analysis of anti-deformation capacity and anti-sliding stability show that the engineering measures are needed to be taken to the diabase dikes,so as to meet the requirements of arch dam construction.The specific engineering measures are introduced.