摘要
桩墩冲刷是海上建筑物安全的最大威胁之一。随着“主墩-承台-群桩”式复合桩墩的广泛运用,承台埋深对其局部水动力及冲刷的影响尚有待研究。本文基于水动力和泥沙输运模块,构造了均匀来流中具有不同埋深承台的复合桩墩水动力及泥沙运动的三维数值模型,并利用水槽试验进行验证。在此基础上,对均匀来流中不同承台相对埋深下桩墩的局部冲刷进行了模拟。结果表明,复合桩墩附近在来流初始时刻的床面最大切应力及最大冲刷深度随承台相对埋深的增大呈“马鞍型”变化趋势;当相对埋深为1.5时,冲刷深度达到极大值,相对埋深为-1.0时达到极小值,此时的承台发挥类似护圈的缓冲效用。建议在冲刷剧烈时将复合桩墩的承台上表面埋设在原床面以下,以减少冲刷程度和防护成本。
Local scour is one of the biggest threats to marine structure safety.With the wide application of the complex pier,which is composed of the main pier,the cap,and the piles,it is necessary to explore the influence of the buried depth of the cap on the local scour around complex pier.In this paper,a three-dimensional hydrodynamic and sediment transport model with different buried depth of cap in uniform flows was constructed based on the hydrodynamic and sediment transport modules of the FLOW-3D software,which was validated using the corresponding flume experiments.On this basis,the local scour at different relative buried depths in uniform flows was simulated.The results show that the maximum shear stress of the bed near the complex pier at the initial time of incoming flow and the maximum shear stress of the pier has a“saddle-shaped”variation against the relative buried depth.When the relative buried depth is 1.5,the scour depth became a relative maximum value,and when the relative buried depth is-1.0,it became the minimum value.Finally,for the condition with severe scouring,the upper surface of the complex pier cap is suggested to be buried below the original bed to reduce the scouring degree and protection cost.
作者
杜登轩
乐绍林
周欢
Htay Htay Aung
喻国良
DU Dengxuan;YUE Shaolin;ZHOU Huan;Htay Htay Aung;YU Guoliang(School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;China Communications Construction Company Road and Bridge Special Engineering Co.Ltd.,Wuhan 430062,China)
出处
《海洋工程装备与技术》
2022年第2期64-71,共8页
Ocean Engineering Equipment and Technology
基金
国家自然科学基金项目(52171268)。
关键词
复合桩墩
局部冲刷
数值模拟
承台
埋深
complex pier
local scour
numerical simulation
pile cap
buried depth
