市政桥梁大体积素混凝土裂缝控制技术研究

Study on Control Technology of Cracks in Mass Plain Concrete of Municipal Bridges

天保湾大桥是天府新区锦江生态带整治项目(二期)中的其中一座,位于天府新区成都直管区沈阳路西段,西接益州大道,东连天府大道南段,是锦江西片区接入天府大道的重要通道。主桥为跨径230m的中承式钢桁架拱桥,位于东、西岸两侧桥头堡之间。桥头堡坐落于扩大基础上,扩大基础采用三层C35素混凝土设计,单层扩大基础最大方量为3626.6m3,属于大体积素混凝土结构。由于扩大基础是整个主桥的主要受力结构之一,因此,扩大基础的施工质量将直接影响到整个主桥的耐久性及结构功能,其中大体积混凝土的裂缝控制即成为重中之重。介绍了市政桥梁大体积素混凝土裂缝的控制过程。

Tianbaowan Bridge is the one bridge of the Jinjiang Eco-belt Renovation Project (Phase II) in Tianfu New Area, which is located in the west section of Shenyang Road, Tianfu New Area (Chengdu Direct Management Area). It connects Yizhou Avenue in the west and south Tianfu Avenue in the east. It is an important passageway for Jinjiang West Area to access Tianfu Avenue. The main bridge is a midheight deck steel truss arch bridge with a span of 230m, which is located between the bridgehead on both side of the east and west bank. Bridgehead is located on the enlarged foundation which is designed with three layers of C35 plain concrete. The maximum concrete quantity of single-layer enlarged foundation is 3626.6m3, which belongs to mass plain concrete structure. As the enlarged foundation is one of the main stress structures of the whole main bridge, the construction quality of the enlarged foundation will directly affect the durability and structural function, among which the cracks control of mass plain concrete becomes the most important. The control process of cracks in mass plain concrete of municipal bridges is introduced.