深圳至中山跨江通道工程总体设计

摘要

深圳至中山跨江通道是世界上首例集超宽超长海底沉管隧道、超大跨海中桥梁、深水人工岛、水下互通“四位”一体的集群工程,采用双向8车道高速公路技术标准进行设计.针对工程技术特点及难点,工程设计方案和技术创新如下:1)提出“标准化、工厂化、智能化、一体化”的设计理念,完成深圳至中山跨江通道总体设计方案研究——海中隧道采用钢壳混凝土组合结构沉管隧道方案,管节宽度达46～55.5 m,伶仃洋大桥采用悬索桥方案,主跨为1 666m、主塔高度为270 m,西人工岛采用直径达28 m超大钢圆筒临时围护方案,实现快速成岛.2)总结沉管隧道钢壳混凝土组合结构设计施工、高强自密实混凝土配制、浇筑工艺及质量检测、沉管隧道深层水泥搅拌桩(DCM)基础设计施工、大型海域地下互通立交设计施工、超大跨整体箱梁悬索桥颤振抗风稳定性设计、离岸深水海中锚碇设计施工等关键技术,研发了沉管浮运安装一体化装备,有力保障了工程的顺利实施.%Shenzhen-Zhongshan River-crossing Link is the first super integrated project in the world that consists of four different types of structures,i.e.ultra-long and wide immersed tunnels,super-large span sea-crossing bridges,deepwater artificial islands and undersea interchanges.The river-crossing is designed for two-way and 8-lane as per highway technical standards.Based on project characteristics and its technical difficulties,engineering solutions and the associated technology innovations have been listed as follows:(1) Proposed a design concept of standardization,industrialization,intelligence and project integration,and completed the study of overall design of Shenzhen-Zhongshan River-Crossing Link.An immersed tunnel with a combined steel-shell and concrete composite structure is designed and the width of tunnel elements is from 46 to 55.5 m;Lingdingyang Bridge has been designed as a suspension bridge with a 1 666 m main span and two 270 m high main bridge towers.For West Island,a temporary enclosure caisson structure made of ultra-large steel cylinders with a diameter of 28 m is designed to achieve a rapid artificial island formation.(2) Summarized the design and construction solutions related to combined steel-shell and concrete structural immersed tunnel,the mix design,batching and concrete casting methods of high-strength self-compacting fluidized concrete,concrete quality check and inspection,design and construction of deep cement mixed (DCM) pile foundation for immersed tunnels,design and construction of large-scale undersea dimensional transport interchange,flutter and wind stability design for super-large span suspension bridge with monobox girders,and key techniques related to design and construction of offshore anchorage in deep sea.Furthermore,an equipment is developed and innovated for not only transport,also for installation of immersed tunnel elements to ensure the implementation of the project in an effective and economical way.