河流岸滩挫落崩塌机理及其分析模式

摘要

In order to study the mechanism and analysis mode of sinking failures, the paper analyzes the mechanical mechanism and process of sinking failures by analyzing the soil properties and geologic structures of the river bank and combining the stress distribution and variation characteristics of the river bank soil. It reveals that longitudinal cracks appeared at the top of the viscous bank accelerate the sinking failures during the process of bed degradation, and the process of the sinking failures is relatively simple and short with a plane failure surface. Based on the analysis on the mechanical equilibrium of bank collapses, the analysis mode of sinking failures was studied and a stable analytical equation of sinking failures was derived. The equation shows the interaction among soil properties, slope form, bed scour and bank seepage, and it can be employed to derive the critical height formulas of bank sinking failures. The rationality of the analysis mode was verified by the field measurements. The results suggest that it is rational and can be used in engineering applications.%为探讨岸滩挫落崩塌发生的机理和分析模式，通过分析河流岸滩土壤特性和地质结构，结合岸滩土体应力分布与变化特点，深入分析了岸滩挫落崩塌的力学机制和崩塌过程，指出在河床冲刷下切过程中，黏性岸滩顶部出现的纵向裂隙会促使岸滩挫落崩塌的发生，发生过程相对简单和短暂，破坏面为平面；根据岸滩崩塌体力学平衡分析，探讨了岸滩挫落崩塌的分析模式，导出了挫落崩塌的稳定分析方程，该方程反映了河岸土壤特性、岸坡形态、河床冲刷、岸滩渗流等因素的共同作用关系，将其应用于岸滩临界崩塌高度公式的推导，并利用实测资料对挫落崩塌分析模式的合理性进行了检验，结果表明该分析模式是合理的，可以在实践中应用。