堰塞坝溃决模拟研究综述与展望

堰塞坝几何形态、粒径级配和库容决定了其溃决机理的复杂性,而溃决过程的精细模拟和峰值流量的准确预测是应急处置的基础和关键.堰塞坝溃决过程与模拟技术是面向国家防灾减灾重大需求的前沿热点问题.在系统梳理国内外试验和数值模拟研究进展的基础上,指出以往试验研究坝体尺度小,足够大的库容基本未模拟,难以显示最终溃口形态;数学模型假设...

Review and Prospects of Landslide Dam Breaching Modelling

Determined by its geometric feature, material composition and reservior capacity, the breaching mechanism of natural landslide dam is rather complex. Finely modeling the breaching processes and accurately predicting peak discharge are foundations and key aspects in support to emergency measures, which are also the research focuses facing demands of national hazard prevention and mitigation. In this paper we systematically review previous experiments and numerical studies on landslide breaching, and conclude that the scale of previous experiments were small and the effect of lake volume was not considered, which failed to model the final shape of breach. Meanwhile, physical mechanisms in the existing numerical models were not complete and thus introducing too much unnecessary hypotheses, which requires further development. Large-scale experiment is proposed to study the breaching mechanism and the process of landslide dam. Coupled hydrodynamic-morphological model is recommended to simultaneously model the whole filed and processes including hydrodynamics in the lake, dam breaching process and propagation of resulting flood in the downstream. The new model abandons hypotheses for discharge, shape, side slope, residual dam height and breaching time, which are instead rendered as part of the model solution. Hence, the modelling capacity and prediction accuracy of landslide dam breaching are expected to be largely enhanced.