基于能量法的植被混凝土路堑边坡泥沙冲刷量计算模型优化研究

Research on Optimization of Calculation Model for Sediment Erosion of Vegetation Concrete Cutting Slope Based on Energy Method

根据植被混凝土坡面冲刷特性,优化设计了能量法计算模型,使其能应用于植被混凝土路堑边坡施工初期的坡面泥沙冲刷量计算。结合室内边坡冲刷试验,设计1∶0.75、1∶1和1∶1.25等3种坡率,在2.5mm/min的降雨强度下进行冲刷试验,通过实测数据和原始模型计算结果对优化模型的合理性进行了验证,同时分析了泥沙冲刷量与降雨历时的关系。研究结果表明:泥沙冲刷量与降雨历时呈对数增加关系;优化模型降雨前期泥沙冲刷量增加迅速,后期增加趋势逐渐稳定,符合真实的植被混凝土边坡冲刷特性;优化模型在降雨前期与试验实测值匹配较好,历时20~50min时相对误差较小,均在15%以内,模型能很好地匹配植被混凝土边坡泥沙冲刷量的计算。

According to the erosion characteristics of vegetation concrete slope,the energy method calculation model was optimized and designed,so that it can be applied to the calculation of slope erosion amount in the initial stage of vegetation concrete cutting slope construction.Combined with the indoor model slope scouring test,the slope rates of 1∶0.75,1∶1,and 1∶1.25 were designed and the scouring test was carried out at a rainfall intensity of 2.5 mm/min.The rationality of the optimized model was verified by the measured data and the calculation results of the original model.At the same time,the relationship between the amount of sediment erosion and rainfall duration was analyzed.The results of the study show that:the amount of sediment erosion and the rainfall duration show a logarithmic increase;the optimized model has a rapid increase in the amount of sediment erosion in the early stage of rainfall,and gradually increases in the later period,which is in consistent with the true vegetation concrete slope erosion characteristics;the optimized model matched well with the experimental measured value in the early period of rainfall,and the relative error was relatively small at 20~50 minutes,all within 15%andthe model can well match the calculation of the vegetation concrete slope sediment erosion.