Khlong Pa Bon Dam in Thailand underwent the greatest differential drawdown in impounded water in 2014. Unexpected deformation of the upstream slope of the dam was observed on June 27 in the year, after operation for 10 years. The drawdown was hypothesized as the possible cause of the slope deformation. The results from piezometers showed that the upstream slope remained partially undrained after sudden drawdowns. A rapid drawdown analysis confirmed that the movement did not occur due to the sudden drawdown of water in 2014. Back analysis revealed that the shear strength of the embankment slope was near its residual value at the time of failure, which was validated by the movement of inclinometers. Ring shear tests were used to determine the residual shear strength of the failure zone, and the results were validated by the finite element method in ABAQUS. Furthermore, the results of the numerical analysis demonstrated that strain softening was the major cause of the slope movement.

泰国空巴邦大坝在 2014 年发生了最大的蓄水差异降水位。在运行 10 年后，当年 6 月 27 日观察到大坝上游斜坡的意外变形。下降被假设为斜坡变形的可能原因。压力计的结果表明，在突然下降后，上游斜坡仍然部分不排水。快速压降分析证实，2014年水位突然回落并未发生该运动。 反分析显示，路堤边坡的抗剪强度接近其破坏时的残值，通过倾角仪。环剪试验用于确定破坏区的残余剪切强度，并通过ABAQUS中的有限元方法对结果进行了验证。此外，数值分析的结果表明，应变软化是斜坡移动的主要原因。