深中通道西人工岛现浇隧道大体积混凝土控裂技术

Crack control technology of mass concrete in cast-in-situ tunnel of west artificial island of Shenzhen-Zhongshan Link

深中通道西人工岛现浇暗埋段隧道是目前国内结构断面尺寸最大的单箱双室管廊箱型结构,工程耐久性及结构防水等级要求高,从而对混凝土控裂提出了较高的要求。结合在深中通道西人工岛现浇隧道中的工程实践,利用有限元仿真模拟、优化结构分层分段工艺、优化混凝土配合比、全方位温控措施等综合手段,对混凝土控裂技术进行研究。结果表明,大体积混凝土控裂效果显著,降低了有害裂缝的发生概率。

The cast-in-situ buried tunnel in the west artificial island of Shenzhen-Zhongshan Link is a single-box,doublechamber tube corridor box structure with the largest cross-section in China at present.The engineering durability and structural waterproof grade are required to be high,which puts forward higher requirements for concrete crack control.Combined with the engineering practice of the cast-in-situ tunnel in the west artificial island of Shenzhen-Zhongshan Link,the concrete crack control technology was studied by means of finite element simulation,optimization of structure layering and subsection process,optimization of concrete mix ratio,comprehensive temperature control measures.The results show that the crack control effect of mass concrete is remarkable and the occurrence probability of harmful crack is reduced.