麻栗坝水库拦河坝沉降变形的研究与对策

Research and countermeasures of settlement deformation of Maliba Reservoir barrage

麻栗坝水库拦河坝地质条件复杂,坝轴线长1172m,在坝体范围内,分布有上第三系20多个地层,地层之间的力学指标差异较大。如何解决坝体不均匀沉降是拦河坝工程的关键技术问题。为保证大坝的安全,在设计中按经典理论计算,开展实体模型试验,成果相互比较,采用分期、分段预压的设计和施工筑坝技术,将坝体分三期施工来减缓和消除不均匀沉降,尽量把较大的沉降量消除在施工期。水库建成后3年,经观测坝体的最大沉降为1.2cm,成功解决坝体不均匀沉降问题。

Maliba reservoir barrage has complex geological conditions. The dam axis is 1172m long. More than 20 formations of the tertiary are distributed within the scope of the dam. The mechanics index differences among the formulations are greater. How to solve differential settlement of the dam is a key technical problem of barrage projects. The physical model test is carried out in order to ensure the safety of the dam according to the classical theory calculation in the design. Results are compared mutually. Dam design and construction technology of preloading in stages and sections is adopted. The dam body is constructed in three stages for alleviating and eliminating uneven settlement. Larger settlement is eliminated in the construction stage as far as possible. The maximum settlement of the dam is 1.2cm according to observation within 3 years after the reservoir is constructed. Uneven settlement of the dam is solved successfully.