河流岸滩冲刷笛卡尔架构块抛投防护效果试验

摘要

The concrete blocks like Cartesian space(CBLCS)have an obvious protection function for the local scour near the riverbank. However,the tentative engineering application of the CBLCS shows that the protection factors have a very great influence on the protection effect. In order to optimize engineering design of the CBLCS for the local scour near the riverbank,the paper further studied the relationship between the protection parameters and the reduction rate of flow velocity which was located in the longitudinal axis of symmetry of protection engineering near the riverbed,and deeply analyzed the influence of the layout density,length-width ratio,layout length,layout width and layout interval for protection effect of the concrete blocks like Cartesian space. The research results show that the protection effect of the CBLCS is the best when the layout density is greater than 0. 2,the length-width ratio is selected from [9,13],the layout length is greater than 30m and layout interval is not greater than 1. 6 times of the layout length.%笛卡尔架构块对河流岸滩冲刷具有较为显著的防护效果，但初步的工程应用表明防护参数对其防护效果的影响较大，为了优化笛卡尔架构块防冲护岸工程设计，通过室内水槽试验深入研究了布设密度、杆件长宽比、布设长度、布设宽度、布设间距等防护参数与笛卡尔架构块防护体系内部及上下游不同位置处的纵向近底流速削减率之间的关系，并依据近底流速削减率随防护参数的变化规律深入分析了防护参数对笛卡尔架构块减速防冲效果的影响。结果表明，布设密度大于0．2、杆件长宽比的取值范围为[9，13]、布设长度大于30 m、布设间距不超过1．6倍布设长度时的防护效果最好。