土石坝溃坝参数模型研究

土石坝溃坝参数的获取对于溃坝致灾后果的评价具有重要意义。而参数模型因其公式形式简单、计算快速常被用于溃坝参数的预测。本文对国外土石坝溃坝案例数据信息进行校验整理,并补充了相关的国内溃坝案例,形成了一个包含154个溃坝案例的基础数据库。在此基础上,针对不同坝型,对模型输入变量进行无量纲化处理,选择库容形状参数、水位比参数及坝高参数等作为自变量进行回归分析,建立了可模拟土石坝溃口峰值流量、溃口最终平均宽度和溃坝历时的数学表达式。该模型可反映坝型、溃坝方式、溃坝时库容、水位、坝高、溃口深度等参数对溃坝参数的影响。通过与国内外常用溃坝参数模型的对比发现,本文模型依据的土石坝溃坝案例数据库信息更为翔实,输入变量较易获取,在整体上具有更好的适应性、计算精度和拟合效果再选取4组典型案例,验证了本模型的合理性和优越性。

Parametric Model for Breaching Analysis of Earth-rock Dam

The acquisition of earth-rock dam breaching parameters has significant importance for the evaluation of the consequences of dam failure. Owing to the simple forms and fast computation speed, the parametric model is often used to predict the breaching parameters. After collecting and checking the data of existing dam failure cases abroad, extra related cases in China are also collected, then a basic database containing 154 dam breach cases with detailed information is formed. Taking dam types, the reservoir shape coefficient, the ratio of water level to breach depth and the dam height as independent variables into account, the regression analysis method is adopted to establish dimensionless formulas for peak outflow discharge, final average breach width and failure time. The model can consider the influence of dam type, failure type, storage capacity, water level, dam height and breach depth for dam failure parameters. The comparison of the present model and common used models indicates that, the present model has the advantage of more measured dam breach cases and easier acquisition of input variables, as well as better adaptability and accuracy and imitative effect. Furthermore, four typical breach cases were selected to verify the rationality and superiority of the present model.