基于有限元方法的不良地质条件下碾压土石坝渗流及边坡稳定性分析

Finite element analysis of seepage and slope stability of the rolled earth-rock dam under adverse geological conditions

碾压土石坝是我国中小型水利工程最常用的坝型之一,早年建设的碾压土石坝因设备和技术限制,如今常存在渗漏、设备老旧等问题。以马屋山水库土石坝除险加固工程为例,对该土石坝劈裂灌浆后的坝体渗流和边坡稳定进行有限元建模分析,结果表明:正常运用条件下,坝体浸润线位置变化不大,等水头线分布均匀,渗透坡降远小于允许值,整体较安全;水位骤降条件下,上游坝坡存在出逸点,混凝土面板护坡起到保护作用;坝体在多种运行工况下均能满足滑动安全要求,不会发生滑坡危险。

The rolled earth-rock dam is one of the most commonly used dam types for small and medi-um-sized water conservancy projects in China.Due to equipment and technical limitations,rolled earth-rock dams constructed in the early years often suffer from problems such as leakage and outdated equip-ment.Based on the earth rock dam reinforcement project of Mawushan reservoir,finite element model-ing analysis is conducted on the seepage and slope stability of dam body after split grouting.The results show that under various working conditions,the position of infiltration line in dam body does not change much,the distribution of equal head lines is uniform,the seepage gradient is much smaller than the al-lowable value;under the condition of sudden drop in water level,there is an escape point on the up-stream dam slope,and the concrete panel slope protection can play a protective role;dam body can meet the sliding safety requirements under various operating conditions,and there is no risk of landslides.