抗裂剂与温控工艺协同调控深中通道东人工岛堰筑段隧道侧墙结构控裂应用技术研究

Research on application technology of anti-cracking agent and temperature control technology to control the crack control of side wall structure of tunnel in the east artificial island weir construction section of Shenzhong Link

为解决深中通道东人工岛堰筑段现浇隧道主体结构侧墙的早期收缩开裂问题,在现有工况开裂风险评估的基础上,提出内掺抗裂剂并与温控工艺协同调控的方法来降低混凝土开裂风险。试验段监测结果对比发现,抗裂段温度及变形监测结果均显著优于基准段,最大温峰值降低约22%,温升膨胀变形增幅超100%,实体结构拆模结果也表明抗裂段控裂方案切实有效。研究成果可为大体积强约束高强现浇隧道混凝土结构控裂设计提供参考。

In order to solve the problem of early shrinkage cracking of the side wall of the main structure of the Shenzhong Link in the east artificial island weir construction section of the deep-middle passage,based on the cracking risk assessment of the existing working conditions,a method of mixing anti-cracking agents and coordinating with the temperature control process is proposed to reduce the risk of concrete cracking.Compared with the monitoring results of the test section,it is found that the temperature and deformation monitoring results of the anti-cracking section are significantly better than those of the reference section,the maximum temperature peak is reduced by about 22%,and the temperature rise expansion deformation increases by more than 100%.The split plan is effective.The research results can provide a reference for the crack control design of large-volume and strong-restrained high-strength cast-in-situ tunnel concrete structures.