主、副隔舱式大圆筒人工岛围堰的稳定性分析  

The stability of the large cylindrical cofferdam structure with main and deputy compartments applied in artificial island

作　　者：肖忠[1,2] 王元战[1,2] 

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300072 [2]天津市港口与海洋工程重点试验室,天津300072

出　　处：《交通科学与工程》2014年第3期63-69,共7页Journal of Transport Science and Engineering

基　　金：国家自然科学基金项目(51109157);天津市应用基础与前沿技术研究计划项目(12JCQNJC04900);高等学校博士学科点专项科研基金项目(20110032120049);大连理工大学海岸和近海工程国家重点实验室开放基金项目(LP1106)

摘　　要：对于建设在软土地基上的跨海桥隧人工岛,采用主、副隔舱式大圆筒围堰是一个非常适合的结构方案,因尚无规范可循,其稳定性亟待研究。结合某工程,通过三维弹塑性有限元计算得出:施工期在围堰内、外侧土压力和水压力差的共同作用下,大圆筒结构的稳定性安全系数最小。当增加大圆筒结构的入土深度并且筒底下沉至持力层时,结构稳定性大幅提高。施工期在波浪荷载作用下,主、副隔舱式大圆筒围堰结构的变位模式主要为绕筒底以上靠近筒底处的某点发生转动变位。施工期大圆筒围堰在内、外侧土压力和水压力差的共同作用下,结构的变位模式主要为平动,并伴随一定的转动,转动点位于大圆筒筒底以下。并且当大圆筒入土深度增加后,结构的转动运动模式更加明显。极限状态时,筒壁与海侧土体间发生了分离现象,并且大圆筒入土深度浅时筒土分离的区域比较大。该研究成果可为类似结构的设计和应用提供参考。The large cylindrical cofferdam structure with main and deputy compartments is suitable for soft foundation in artificial island of bridge and tunnel over strait.Because there is no standards to follow,the stability of this structure is urgent to study.3Delastic-plastic finite elemental models were established for the stability analysis of this structure according to a project.The results show that the stability safety factors of the large cylindrical structure have different minimum values under soil and water pressures inside and outside the cofferdam structure in construction periods.Furthermore,when the embedded depth of the structure was increased,and the bottom of the structure was sunk into supporting layers,its stability increased sharply.In addition,it was obtainedthat the displacement mode of this structure under wave force in construction periods was the rotation of some point over its bottom.And it was also obtained that the displacement mode of this structure under soil and water pressures in construction period was mostly translated with a certain rotation of some point under its bottom.When the embedded depth of the large cylindrical structure was increased,its rotation becomes more obvious.And separations were formed between the cylinder wall and the seaside soil.The separations became larger when the embedded depth of the large cylindrical structure was decreased.The present research could be as a reference for the design and application of the structure.

关 键 词：大圆筒结构 人工岛 稳定性 隔舱 有限元法 

分 类 号：U656.6[交通运输工程—港口、海岸及近海工程]