底床粉质土液化下波动水体含沙量垂向L型分布特征试验研究

根据现场大风浪条件下的实测资料,粉质土海岸水体中的含沙量沿垂向具有上部均匀、近底突增的分布特点,即呈L型分布特征。利用黄河三角洲粉质土作为试验底床开展波浪水槽试验研究,揭示了底床粉质土在波浪作用下产生液化情况的水体含沙量沿垂向存在L型分布特征。根据试验现象以及悬沙粒度变化,分析认为底部高含沙层的形成主要受粉质土液化后细颗粒析出的影响,上部水体中悬沙由湍流脉动维持。对粉质土海岸大风天气期间水体含沙量剧烈增加采用波致粉质土液化的观点进行了初步解释。

An experiment study on L-shaped vertical characteristics of suspended sediment content on the liquefied silty soil bed

Based on measured data in storm waves, the suspended sediment content of silty coast water is uniform at the upper layer, with a sudden increase near the bottom, and is named as L-shaped vertical distribution. Flume experiments were carried out to study the characteristics of vertical suspended sediment content on the liquefied silty soil bed, which is made using Huanghe River Delta silty soil. It is revealed that the vertical suspended sediment content on the liquefied silty soil bed under wave action is L-shaped.According to the variation of the particle size and the experiment phenomena, the formation of the high content layer at the bottom was affected by the fine sediments entering into the water when the silty soil liquefied, and the suspended sediments in the upper water was kept by turbulent fluctuation.The dramatic increase of the water-sediment on the silty soil coast during stormy weather is preliminarily explained using wave-induced soil liquefaction point of view.