多软弱夹层坝基高重力坝深层抗滑稳定与加固措施研究

抗滑稳定分析是多软弱夹层高重力坝坝基设计工作中的关键内容。针对某一高重力坝工程,采用刚体极限平衡三滑面法与有限元强度折减法相结合的研究手段,开展了抗滑稳定计算分析,并确定了适宜的泥化夹层坝基处理措施。研究结果表明,刚体极限平衡三滑面法与双滑面法相比,抗滑稳定结果更为准确、合理,更适合用于软弱夹层坝基的重力坝深层抗滑稳定计算;提出的4种坝基处理方案中,抗剪洞方案的安全可靠性高、工期短、投资低,可优先作为重力坝坝基处理方案;采用有限元强度折减法计算了抗剪洞方案下的坝基深层滑动破坏模式和抗滑稳定安全系数,与三滑面法的计算结果相比,抗滑稳定计算结果相差不大,验证了抗滑稳定分析结果的准确性和所选坝基处理措施的有效性。本研究为类似工程抗滑稳定计算及坝基处理设计提供了参考依据。

Research on the Deep Anti-slide Stability and Reinforcement Measures of the High Concrete Gravity Dam with the Multi-Soft Interlayer Foundation

The anti-slide stability analysis is a critical part in the design of gravity dam foundation with multi-soft interlayer.According to a high gravity dam,the research method combining limited equilibrium method with three sliding surfaces and finite element strength reduction method is adopted.Meanwhile,the anti-slide stability analysis is carried out,and the appropriate treatment measures for the dam foundation with mud interlayer are determined.The results show that compared with the limited equilibrium method with two sliding surfaces,the limited equilibrium method with three sliding can provide a more accurate and reasonable anti-sliding stability results,and is more suitable for the calculation of deep anti-sliding stability of gravity dam with soft interlayer.Among the four dam foundation treatment schemes,the anti-shear hole scheme is highly safe and reliable and has a short construction period,and low investment,and can be preferentially used as a dam foundation treatment scheme.The finite element method strength reduction method is used to calculate the deep sliding failure mode and anti-sliding stability safety factor of the dam foundation under the anti-shear hole scheme.Compared with the three-sliding surface method,the anti-sliding stability calculation results are similar,proving the correctness of the anti-sliding stability analysis and the effectiveness of selected dam foundation treatment measure.This study provides a reference for the anti-sliding stability calculation and dam foundation treatment design of similar projects.