龙滩水电站右岸坝肩边坡不良地质体特征及成因分析

Engineering characteristics of defective geological bodies at right-bank dam abutment of Longtan Hydropower Station and analysis of their causes

龙滩水电站右岸边坡开挖中发现了体积较大的不良地质体，威胁到坝肩边坡和缆机基础的稳定与安全。根据开挖揭露的地质情况，概括了该区的工程地质特征，着重探讨了在顺层边坡或冲沟中坚硬。中等坚硬岩体形成倾倒变形岩体及风化堆积深槽的机制，并对治理后的监测成果进行分析及边坡稳定性评价。监测结果表明，由于及时查明了不良地质体的规模、性状、成因及危害性，为右岸坝肩边坡的治理提供了准确、可靠的地质依据，坡面综合处理后边坡稳定性好。

During the excavation of the fight-bank dam abutment of the Longtan Hydropower Project, large defective geological bodies that threaten the safety and stability of the dam abutment slope and cable crane foundation were discovered. According to the geological conditions revealed by the excavation, the engineering characteristics of these defective geological bodies are summarized, with emphasis on the mechanism of the formation of the cumulatively weathered deep channel in the bedding rock slope or gully. The monitoring results show that the range, properties, harmful effects and causes of the defective geological bodies have been identified and comprehensive measures for dam abutment slope treatment have been employed early enough to ensure the safety of the project.