堰塞坝溃口及洪峰参数模型评估与优化

Evaluation and Optimization of Landslide Dam Breaking and Flood Peak Parameter Models

由滑坡等失稳地质体快速堆积并堵塞河道形成的堰塞坝溃决后会对下游人民生命财产安全造成极大威胁。建立快速准确的溃决参数预测模型,是制定有效防灾减灾措施的必要条件。本文收集了75例包含坝高、库容、溃口峰值流量、坝体冲蚀系数等参数的堰塞坝案例,基于均方根误差、回归相关系数、百分比偏差三个指标对具有代表性的土石坝和堰塞坝参数模型进行评估。通过回归分析建立新的堰塞坝溃口深度预测模型及溃口峰值流量预测模型,将新建模型与现有模型对比,在实际案例中验证了模型的适用性。研究结果表明:现有模型中单参数、双参数及土石坝模型对于堰塞坝溃决参数预测效果不佳,考虑坝体易蚀性的参数模型具有较高准确性,本文所建新模型预测效果有所提升,使用范围更广,预测结果可为堰塞坝的防灾减灾措施提供参考。

Landslide dams are generally caused by the fact that unstable geological bodies like landslide quickly accumulate and block rivers,which pose a great threat to the safety of people's life and property in the downstream area after the breach.Therefore,establishing a fast and accurate prediction model of breach parameters is necessary for hazard prevention and mitigation.In this paper,75 cases of landslide dam failure including parameters like dam height,reservoir capacity,peak discharge of breach and erosion coefficient of dam body were collected.The mean square error E RMS,correlation coefficient R 2 and percentage deviation P BIAS were used to compare and analyze the prediction effect of representative parameter models of earth-rock dam and landslide dam.Through regression analysis,a new prediction model of dam breach depth and peak discharge is established,and the new model is compared with the existing models.Finally,the applicability of the model is verified in actual cases.The results show that the single parameter,double parameters and earth-rock dam models in the existing models are not effective in predicting the dam break parameters,but the parameter model considering the erosivity of the dam has high accuracy.The prediction effect of the new model established in this paper has been improved with wider application,and the prediction results can provide theoretical reference for disaster prevention and mitigation measures of landslide dams.