湿热滨海地区大体积混凝土底板施工温控分析  

Temperature control in construction process for mass concrete foundation slab in hot and humid coastal area

作　　者：郑豪杰 梁思明 门小雄 郭保和 墨飞标 戴北冰 刘建坤 ZHENG Haojie;LIANG Siming;MEN Xiaoxiong;GUO Baohe;MO Feibiao;DAI Beibing;LIU Jiankun(School of Civil Engineering,Sun Yat-sen University,Guangzhou 510275,China;Zhuhai Rail Transit Co.,Ltd.,Zhuhai 519000,China;China Railway Tunnel Group Co.,Ltd.,Guangzhou 511458,China)

机构地区：[1]中山大学土木工程学院,广东广州510275 [2]珠海市轨道交通有限公司,广东珠海519000 [3]中铁隧道局集团有限公司,广东广州511458

出　　处：《混凝土》2023年第5期138-143,共6页Concrete

基　　金：国家自然科学基金(52108263,52078507);广州市科技计划(202002030195)。

摘　　要：湿热环境会加速混凝土的水化反应,增大浇筑前期的放热量,同时也会影响混凝土早期力学与变形性能,进而影响大体积混凝土的早期开裂风险。以珠海隧道工程西岸工作井底板为例,开展湿热滨海地区大体积混凝土施工温控分析。采用有限元方法模拟底板早期温度场和应力场,针对环境温度、环境湿度和混凝土入模温度进行参数敏感性分析,根据有限元仿真结果优化冷却水管布置并开展现场温度监测。结果表明,环境温度和入模温度越高,混凝土内部温度越高,里表温差越大,越容易发生开裂;环境湿度越高,大体积混凝土的收缩应力与变形越小,开裂风险越低;布置冷却水管可以起到很好的温度控制效果,有效防止大体积混凝土的早期开裂;有限元结果与实测结果基本吻合,可为实际施工提供指导。The hot and humid environment can accelerate the hydration reaction of concrete and increase the heat released during the early hardening stage.It also affects the early-age mechanical properties and deformation of concrete,which will in turn influence the cracking risk of mass concrete.The temperature control of mass concrete during the construction process in the hot and humid coastal area was analyzed in this study by focusing on the construction of foundation slab in the Zhuhai Tunnel Project.The numerical simulation was done by finite element method to track the evolutions of the temperature and stress of the foundation slab.The parametric sensitivity analysis was performed to assess the influence of environmental temperature,environmental humidity and moulding temperature on the temperature and stress of concrete slab.Then the arrangement of the cooling pipes was optimized according to the finite element simulation results.The in-situ temperature monitoring of the foundation slab was also carried out to validate the simulation results.The results show that the higher the environmental temperature and moulding temperature,the higher the maximum temperature for the inside of the concrete,and the greater the temperature difference between the outside and inside parts of concrete slab,leading to a higher risk of concrete cricking at the early hardening stage.A higher environmental humidity level can result in less shrinkage deformation and smaller shrinkage stress,which helps reduce the risk of cracking.The arrangement of cooling water pipes can effectively control the temperature and prevent the early-age cracking of mass concrete.The finite element simulation results are basically consistent with the measured results,which can provide guidance for the construction of mass concrete.

关 键 词：大体积混凝土 水化热 温度场 湿热环境 数值模拟 

分 类 号：TU528.01[建筑科学—建筑技术科学]