基于泥沙流变特性的吸力式沉箱减阻技术  

Resistance reduction technology of suction caisson based on sediment rheology

作　　者：钟丹 张民曦 俞梅欣[2,3] 李小军 喻国良[1] ZHONG Dan;ZHANG Minxi;YU Meixin;LI Xiaojun;YU Guoliang(State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;China Shipbuilding NDRI Engineering Co.,Ltd.,Shanghai 200090,China;Shanghai Engineering Research Center of Ocean&Shipbuilding Maritime Engineering,Shanghai 200090,China)

机构地区：[1]上海交通大学海洋工程国家重点实验室,上海200240 [2]中船第九设计研究院工程有限公司,上海200090 [3]上海海洋工程和船厂水工特种工程技术研究中心,上海200090

出　　处：《海洋工程》2022年第6期31-40,共10页The Ocean Engineering

基　　金：国家自然科学基金资助项目(52001206)。

摘　　要：针对吸力式沉箱在黏性底床中沉贯安装的减阻问题,基于黏性泥沙的流变特性,开展了一系列不同振动荷载作用下的室内沉贯模型试验,分析了振动荷载对吸力式沉箱沉贯过程的影响和沉贯减阻效果。试验结果表明:在压力沉贯阶段或吸力沉贯阶段施加高频振动荷载,均能促使吸力式沉箱侧壁周围的土体发生流化,有效降低沉箱的沉贯阻力;减阻效果与振动频率和沉箱的长径比有关,与振动频率成正比,与沉箱的长径比成反比;存在一个临界频率,当振动频率大于该频率后,沉贯阻力随频率的减小不明显;施加高频振动荷载有助于减小吸力沉贯阶段沉箱内的土塞高度,促进沉箱沉贯到位。研究成果可为黏性泥沙流变减阻技术在吸力式沉箱中的应用提供理论依据和技术参考。Based on the rheological characteristics of cohesive sediment,a series of penetration model tests under different vibration loads were conducted to investigate the influence of vibration loads on the penetration process and penetration resistance of the suction caisson.Several useful conclusions are drawn from test results:applying high-frequency vibration loads during the self-weight penetration stage or suction penetration stage can promote fluidization of the soil around the side wall,thereby effectively reducing the penetration resistance of the suction caisson.The resistance reduction effect is related to the vibration frequency of vibration loads and the aspect ratio of the suction caisson,and it increases with the vibration frequency but decreases with the aspect ratio.When the vibration frequency exceeds a critical value,the penetration resistance does not decrease significantly with vibration frequency.Applying high-frequency vibration loads during the suction penetration stage can reduce the height of the soil plug and help the suction caisson penetrate in place.The research can provide a theoretical basis and technical reference for the application of cohesive sediment rheological resistance reduction technology in suction caisson.

关 键 词：黏性泥沙 泥沙流变 吸力式沉箱 沉贯减阻 土塞高度 

分 类 号：P754[天文地球—海洋科学] TU476[建筑科学—结构工程]