老海坝河段抛石护岸工程对河道演变的影响评价

Impact evaluation of rock-revetment and bank-protection projecton old sea dam reach on river course evolution

为研究抛石护岸工程对河道演变的影响程度,基于MIKE 3水沙数值模型建立的河道演变影响综合评价模型,对6种不同的工程方案进行评价指标权重和河道演变影响综合评价系数的计算,并结合工程方案设计原理对评价结果进行综合分析。结果表明:影响抛石护岸工程附近河道演变的主要因素是流速和悬沙浓度,和河道演变的原理保持一致;不同工程方案对河道演变的影响程度和分布状况呈现较大的差异,工程区附近随不均匀度减小而减小,而其他区域随不均匀度呈先增后减的趋势;工程对整个区域的影响随抛石增厚值的增加而增加。研究结果不仅为抛石防护效果的评价提供思路,还为工程的后续管理和维护提供理论基础。

To study the river course evolution on the effect of the riprap engineering based on MIKE3 water and sediment numerical model,constructed the comprehensive evaluation of the influence on the channel evolution,calculated the index weights and the comprehensive evaluation coefficient of river channel evolution,and analyzed the results combined with the engineering design principle.The results showed that the main factors affecting the river evolution near the rip rapping revetment project were the flow rate and suspended sediment concentration,which were in consistent with the principle of river evolution.The degree and distribution of the influence of different engineering schemes on the evolution of river channel were quite different,the area near the engineering decreased with the decrease of the index of unevenness,while the other areas increased first and then decreased.The influence of the project on the larger area increased with the increase of riprap thickening value.The research results could not only provide a new idea for the evaluation of the protection effect of riprap,but also afford a certain theoretical basis for the follow-up management and maintenance for the project.