摘要
挤密砂桩复合地基加固软弱黏性土具有减小沉降、促进排水固结、提高地基承载力及增大稳定性等作用,这种复合地基使得在软土地基中建设海底沉管隧道成为可能。以港珠澳大桥岛隧工程沉管隧道基础工程为背景,介绍了沉管隧道挤密砂桩复合地基加固外海深厚软弱黏性土中的基本原理、设计方法及加固效果。沉管隧道过渡段挤密砂桩复合地基置换率40%～70%,通过堆载预压施工期和下放沉管后的管节沉降监测,大部分管节的总沉降均控制在约8 cm以内,差异沉降小于0.11%,实现了沉管隧道与地基刚柔协调和沉降平稳过渡至人工岛。
The sand compaction pile (SCP) method can be adopted to improve soft marine clay, which composes the composite foundation. The method can reducing settlement, accelerating consolidation, increasing bearing capacity and increasing slope stability, which makes it possible to build the underwater immersed tunnel on soft marine clay. Based on the immersed tunnel foundation of the Hongkong-Zhuhai-Macao Bridge, we introduced the basic principle, design method, and treatment effect of immersed tunnel on soft marine clay by the sand compaction pile method. The replacement ratio of SCP composite foundation in transition section of immersed tunnel is 40% to 70%. With the monitoring and instrumentation during preloading stage and tunnel building stage, most of the total settlement are within an order of 8 cm and differential settlement are within 0.11%. It realizes rigid-flexible coordination between immersed tunnel and foundation and smooth transition of settlement from immersed tunnel to artificial island.
作者
何洪涛
李建宇
林佑高
王坤
HE Hong-tao;LI Jian-yu;LIN You-gao;WANG Kun(CCCC-FHDI Engineering Co., Ltd., Guangzhou, Guangdong 510230,China)
出处
《中国港湾建设》
2019年第5期67-74,共8页
China Harbour Engineering
关键词
挤密砂桩
沉管隧道
软弱黏性土
沉降
sand compaction pile
immersed tunnel
soft marine clay
settlement
