泰州大桥采用主跨为1 080 m三塔两跨悬索桥，中塔位于主江中心。通过对沉井基础和高桩承台钻孔桩基础等多项基础方案的比选，考虑到沉井结构受力明确、刚度大、工序简单，经济性高等优点，中塔基础最终选用沉井基础。根据塔柱底的构造要求，受力要求，沉井采用58 m×44 m四角倒圆的矩形沉井，沉井总高76 m。为了能在深水中顺利施工，沉井下部为钢壳混凝土结构，上部为钢筋混凝土结构。文中介绍了泰州大桥水中沉井的结构构造、施工方法、方案比较以及沉井的设计特点，可为今后类似工程起到很好的借鉴作用。

Taizhou Bridge is a highway triple-tower and double-span bridge with span arrangement of 1 080 m+1 080 m, the middle tower is located in the center of Yangtze River. Several proposals are studied for the foundation type of the middle tower, especially the comparison between caisson foundation and bored pile foundation with higher pile cape. The caisson foundation is adopted because of its concise structural behavior, larger rigidity and simpler construction procedure, and it's far more economic. According to the configuration requirement of the first section and the structural force, the cross-section of the adopted rectangle caisson's dimension is 58 m×44 m with four circle chambers at corners, the total depth of the caisson is 76 m. The bottom segment of the caisson adopts concrete caisson with steel hull, and its upper segment adopts reinforced concrete structure. The structural arrangement, construction method, comparison of the project's proposal and the design feature are introduced in the paper. The design of the caisson foundation will provided good experience for the future similar projects.