张永涛;刘建波;李刚;
ZHANG Yongtao;LIU Jianbo;LI Gang;College of Civil Engineering, Tongji University;CCCC Second Harbour Engineering Co., Ltd.;Key Laboratory of Large-span Bridge Construction Technology;Research and Development Center of Transport Industry of Intelligent Manufacturing Technologies of Transport Infrastructure;

• 1:同济大学土木工程学院
• 2:中交第二航务工程局有限公司
• 3:长大桥梁建设施工技术交通行业重点实验室
• 4:交通运输行业交通基础设施智能制造技术研发中心

摘要(Abstract)：

中马友谊大桥位于马尔代夫北马累环礁，跨越Gaadhoo Koa海峡，连接马累岛和机场岛，桥梁桩基础位于多孔隙、易破碎的珊瑚礁地层，灌注桩竖向承载特性复杂且面临诸多成桩难题。为分析珊瑚礁条件下灌注桩竖向承载特性，开展现场试桩试验，掌握竖向承载力的组成规律及后压浆承载力增强机理。针对钢护筒溜桩、穿越孔洞、清水钻塌孔等工程难题，研发熔断式抱桩器、钢筋笼柔性护套等装置，并提出质量保障措施，以确保大直径灌注桩的施工质量与安全。
The China-Maldives Friendship Bridge is located in North Male Atoll, Maldives. It spans the Gaadhoo Koa Strait and connects Male Island and Airport Island. The bridge pile foundation is located in a porous and fragile coral reef formation. The vertical bearing characteristics of the cast-in-place piles are complex and they are faced with many pile formations. problem. In order to analyze the vertical bearing characteristics of cast-in-place piles under coral reef conditions, field test piles were carried out, and the composition rules of vertical bearing capacity and the mechanism of post-grouting bearing capacity enhancement were mastered. In view of the engineering problems such as steel casing piles, passing through holes, and clear water drilling holes, practical devices such as fusible pile holders and steel cage flexible sheaths have been developed, and a series of quality assurance measures have been proposed to ensure the construction of large-diameter cast-in-place piles.

关键词(KeyWords)： 地基与基础;珊瑚礁地质;灌注桩;现场试桩;承载性能;施工工艺
subgrade and foundation;coral reef geology;cast-in-place piles;field test piles;bearing capacity;construction

Abstract:

Keywords:

基金项目(Foundation): 中国交建重点研发课题：珊瑚礁地质条件下大直径桩基承载性能研究及应用(2016-ZJKJ-PTJS02)

作者(Authors): 张永涛;刘建波;李刚;
ZHANG Yongtao;LIU Jianbo;LI Gang;College of Civil Engineering, Tongji University;CCCC Second Harbour Engineering Co., Ltd.;Key Laboratory of Large-span Bridge Construction Technology;Research and Development Center of Transport Industry of Intelligent Manufacturing Technologies of Transport Infrastructure;

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