连云港30万吨级航道工程疏浚土抛泥扩散的数值模拟研究

Numerical simulation of diffusion of dredged spoil in 300 000 DWT waterway project of Lianyungang harbor

利用二维潮流泥沙数学模型,对连云港航道抛泥扩散观测期间的流场和含沙量进行了模拟计算。在对实测成果验证良好的基础上,研究了各抛泥方案中疏浚土倾倒所产生的悬浮泥沙的扩散规律及其对周边水域含沙量的影响。研究结果表明,采用两艘舱容4 500 m3的耙吸式抛泥船,在拟设抛泥点的流向偏向航道一侧时进行抛泥作业,所产生的悬浮泥沙能较快地沿水流方向扩散,高含沙水体的存在时间及扩散距离均较短,对临近航道含沙量的影响很小。

A 2D tidal current and sediment numerical model was established to simulate the flow field and the sediment concentration during the survey of disposing spoil in Lianyungang waterway. Based on the good certification, the law of the diffusion of the suspended sediment from dredged spoil disposing and its influence on the sediment concentration of nearby water area were studied in different cases. The result of the study showed that if two drag suction dredgers with 4 500 m3 tank volume disposed the dredged spoil at the mud dumping area simultaneously when the flow direction was bias to the nearby waterway, the suspended sediment would spread quickly along the flow direction, the high-concentration water would not last for long and covered a short distance, also it had little influence on the sediment concentration of nearby waterway.