【摘要】 针对传统数值方法在土石坝瞬态渗流模拟中面临的网格依赖性强、显示时间积分步长受限等瓶颈，提出了一种融合光滑有限元法(S-FEM)与无条件稳定隐式时间差分的高效分析方法。该方法在空间离散层面引入梯度光滑策略，将单元域面积分转化为边界线积分，显著降低了对网格质量的敏感性;在时间离散层面构建隐式差分与光滑有限元耦合求解格式，实现了非线性系统的无条件稳定收敛。典型心墙土石坝算例表明:该方法能精准捕捉库水位波动下坝体内部浸润线、水头及渗流速度的时空演化特征，对饱和-非饱和过渡区响应灵敏;与商业软件SEEP/W对比验证显示，该方法在保证计算精度的前提下，显著提升了复杂非线性渗流问题的求解效率与数值稳定性，为土石坝动态安全评估提供了可靠的数值工具。更多还原

【Abstract】 Conventional numerical methods are restrained by strong mesh dependency and limited explicit time integration schemes when simulating transient seepage in earth-rock dams. To address these limitations,this study proposes an efficient computational framework that integrates the smoothed finite element method( S-FEM) with an unconditionally stable implicit time discretization. At the spatial discretization level,a gradient smoothing strategy is introduced to transform domain integrals over elements into boundary integrals along smoothing cells,thereby significantly reducing sensitivity to mesh quality. At the temporal discretization level,an implicit time integration scheme is coupled with the S-FEM formulation to construct a robust nonlinear solution framework with unconditional convergence stability. A representative core-wall earth-rock dam case study demonstrates that the proposed method can accurately capture the spatiotemporal evolution of the phreatic surface,hydraulic head,and seepage velocity under reservoir water level fluctuations,with high sensitivity to the saturated-unsaturated transition zone. Comparative validation against the commercial software SEEP/W shows that,while maintaining computational accuracy,the proposed approach markedly improves both efficiency and numerical stability in solving complex nonlinear seepage problems. The method thus provides a reliable and effective numerical tool for the dynamic safety assessment of earth-rock dams.更多还原