李家河水库河床坝基工程地质问题与处理

Engineering Geological Problems and Treatments for the Riverbed Dam Foundation of Lijiahe Reservoir

李家河水库大坝是陕西省在建的碾压混凝土薄高拱坝。建坝基础要求微风化Ⅱ类岩体。坝基岩性为燕山期侵入花岗岩,建基条件较好。但坝基开挖后局部岩体受构造、风化影响,存在一定的缺陷,不满足建基要求。通过对建基面岩体的工程地质条件分析论证,提出对不满足建基要求的岩体进行挖除换填、锚固、灌浆等工程处理措施。

Lijiahe Reservoir Dam is a thin-high RCC dam under construction in Shaanxi province.The dam foundation needs the weakly weathered rockmass with ClassⅡ.The rock for foundation is Yanshanian instructive granite,having a fine condition.After excavation,because of the influences from structure and weathering,some rockmass are found with defects and are not suitable.By analysis on the engineering geological conditions of the foundation rockmass,some measures such as excavation-change,anchoring and grouting are presented.