【作者】 邓绍云；

【导师】 陈志昌；

【作者基本信息】 南京水利科学研究院 ， 港口、海岸及近海工程， 2007， 博士

【摘要】 圆柱桩群基础在码头、桥梁和海洋平台工程中被广泛应用，研究圆柱桩群阻力特性及其对水流和底床冲淤变化影响具有重要意义，也是正确模拟桩群的关键。本文针对具有自由表面及有限水深均匀流中圆柱桩群阻力特性与桩群对底床冲淤影响研究成果的缺乏，特进行了圆柱阻力水槽试验，得到了圆柱阻力特性研究成果；并通过对各种排列方式、各种迎流角情况下桩群的阻力试验，得到了圆柱横向阻力影响特性和纵向阻力影响特性及迎流角对桩群阻力的影响特性的研究成果，研究得到圆柱阻力横向影响系数k_H与纵向遮流影响系数k_Z及迎流角对桩群阻力影响系数k_θ的计算经验公式，并提出了桩群阻力计算方法，且用桩群阻力试验资料验证了该方法的有效性和准确性，给工程实际中准确把握桩群阻力提供了理论依据。桩群附近水域底床局部冲淤也是桩群模拟必须考虑的一个因素，为此，本文特进行了不同桩群在同一水流中对附近水域底床局部冲淤影响比较试验，和同桩群在不同水流中对附近水域底床局部冲淤影响比较试验，得到了桩群附近水域底床局部冲淤变化规律。发现桩群的排列方式对桩群附近水域底床局部冲淤具有很大的影响力度，同时发现不同水流中桩群附近水域底床局部冲淤特性有所差别。通过研究发现，桩群桩柱排列方式对桩群阻力特性、桩群附近水域底床局部冲淤特性具有很大的影响程度，指出正确模拟桩群必须在做到阻力相似的同时尽量考虑桩群的桩柱排列方式相同。更多还原

【Abstract】 Cylinder pile cluster foundation is extensively used in wharfs, bridges and oceanicplatform projects. Studies on drag force characteristics of cylinder pile cluster anderosion-disposition influence imposed on flow and bottom bed are of importance and alsothe key to successfully simulate pile cluster.The dissertation aims at the shortage of data on drag force characteristics of cylinder pilecluster in uniform flow with free surface and limited water depth, and carries on flume testson cylinder pile cluster drag force and acquires drag force characteristics of cylinder pile;tests drag force of pile cluster with various arranging formats and up-flow angles, recognizeslaw of up-flow angles influencing drag force of pile cluster, finds empirical formula ofcalculating pile cluster drag force coefficient ko from horizontal influencing coefficient k_H,vertical flow-covering coefficient and up-flow angle, puts forward calculating method andformats about drag force of pile cluster, effectiveness and precision of which is verified bytest data, and supplies theoretical base for precisely computing drag force in projects.Local erosion-deposition of bottom bed near pile cluster is also a factor that must beconsidered in simulating pile cluster. Therefore, the dissertation makes comparative tests oflocal erosion-deposition among different pile clusters in the same flow, and among the samepile cluster in different flows, and acquires local erosion-deposition laws of pile cluster nearbottom bed. It is found that arranging format of pile cluster has much influence on localerosion-deposition near bottom bed, and that some difference exits between localerosion-deposition characteristics at bottom bed near pile cluster in different flows.Arranging format of pile cluster has much influence on characteristics of drag force andlocal erosion-deposition near bottom bed. It is necessary for successfully simulating pilecluster to consider as much as possible arranging of pile cluster while drag force similarity issatisfied.更多还原