筒型基础防波堤稳定性有限元数值分析  

Finite element analysis of the stability of bucket foundation breakwater

作　　者：肖忠[1] 王元战[1] 及春宁[1] 李元音[2] 谢善文[2] 

机构地区：[1]天津大学建筑工程学院港口与海洋工程教育部重点实验室,天津300072 [2]中交第一航务工程勘察设计院有限公司,天津300222

出　　处：《土木工程学报》2009年第7期119-125,共7页China Civil Engineering Journal

基　　金：国家自然科学基金(50779043);西部交通建设科技项目(200632800003-06)

摘　　要：筒型基础防波堤是一种新型港口与海岸工程结构,依靠下部筒型基础沉入土中维持结构稳定。结合实际工程,建立筒型基础防波堤稳定性分析的三维弹塑性有限元模型。根据筒型基础防波堤的结构特性,建议此种结构稳定性分析的4种判别标准,分别为极限承载力判别标准、基于P-S曲线出现较明显拐点的判别标准、基于允许变位的判别标准和基于筒底脱离的临界点的判别标准。通过有限元分析结果得出各种判别标准下结构的安全系数。结果表明在设计波浪力以内,结构的位移很小,P-S曲线为线性,说明这种新型结构具有很好的稳定性。并且通过分析极限状态下结构位移场的分布,得出这种新型防波堤的失稳模式为绕基础筒底以下某点发生转动失稳。研究成果可为这种新型结构的稳定性分析提供借鉴和参考。Bucket foundation breakwater is a new type of structure in port and coastal engineering. Its stability is sustained by the bucket foundation penetrated into the soil. A 3-D elastoplastic finite element model was established for the stability analysis of a bucket foundation breakwater. Four criterions to judge the stability of the structure, based on ultimate bearing capacity, inflection point in P-S curves, allowable displacement and critical contact states between cylinder bottoms and the soil, were proposed according to the structural characteristics of the bucket foundation breakwater. For each criterion, safety factor for the structure was obtained through finite element analysis. The calculation results showed that the structural displacement was small and P-S curves were linear for the design wave force, indicating good stability of the structure. It was found that instability occurred in the form of rotation of the bucket foundation breakwater around a point below the foundation base, resulted from the displacement field distribution of the structure in the limit state. The present research could be a reference for the stability analysis of the new type of structure.

关 键 词：简型基础 防波堤 稳定性 判别标准 有限元模型 

分 类 号：U656.2[交通运输工程—港口、海岸及近海工程]