人工填筑黏性土起动冲刷特性试验

为了研究人工填筑黏性土起动和冲刷特性,采用资料分析和试验相结合的方法,研究人工填筑黏性土的起动冲刷特性。根据试验资料,结合力学特性确定影响人工填筑黏性土起动冲刷的主要因素;根据试验结果分析人工填筑黏性土起动切应力、冲刷率分别与各自的影响因素之间的对应关系,提出了量纲和谐的起动切应力和冲刷率的公式,运用多元线性回归方法确定了公式中的系数和指数,并分析比较了人工填筑黏性土和黏性泥沙起动和冲刷特性。结果表明:人工填筑黏性土的黏结力比自然淤积固结的黏性泥沙大得多,较难起动和冲刷,需要较大的水流切应力;干密度对自然淤积黏性泥沙冲刷率影响比对人工填筑黏性土要大。

Experiment on incipient motion and scour features of artificial filling clay

The combined method of data analysis and experiment is used to study the incipient motion and scour features of artificial filling clay.The main factors for the incipient motion and scour of the artificial filling clay are determined based on the experimental data and mechanical properties.According to the experimental results,the correlations between the incipient shear stress and scour rate of the artificial filling clay and their influencing factors are analyzed,and two dimensional formulas for the shear stress and scour rate are put forward.The multiple linear regression method is employed to determine their coefficients and exponents.The incipient motion and scour features of the artificial filling clay and natural cohesive sediment are analyzed and compared.The results indicate that the bond strength of the artificial filling clay is much greater than that of the natural cohesive sediment.Therefore,it's more difficult to start and be scoured,which needs a larger shear stress of water flows.The influence of the dry density on the scour rate of the natural cohesive sediment is larger that of the artificial filling clay.