福建某碾压混凝土重力坝温控仿真及温控标准研究

Research on Temperature Control Simulation and Temperature Control Standard of a RCC Gravity Dam in Fujian

亚热带地区高温季节气温与热带相似,且昼夜温差大,对大坝混凝土温控防裂较为不利.本文以福建省某典型碾压混凝土重力坝工程为例,采用有限元法开展了大坝混凝土温控措施及温控标准研究.基于稳定温度场计算结果,依托规范并参考相似工程提出相应温控标准;通过不同方案对浇筑温度、冷却水温和水管间距等温控措施进行了敏感性分析,并据此给出了推荐温控方案.仿真结果表明不采取温控措施时各区最高温度均不能满足控制要求;最高温度对浇筑温度较为敏感,但只控制浇筑温度时,后期内部温度下降缓慢,可能在低温季节产生较大的内外温差而导致表面开裂;综合考虑浇筑温度及通水冷却,可有效降低最高温度及后期内外温差.研究成果可为亚热带地区的类似工程提供参考.

The temperature in subtropical region is similar to that in tropical region,and the temperature difference between day and night is large,which is disadvantageous to dam concrete temperature control and crack prevention.Taking a typical RCC gravity dam project in Fujian Province as an example,this paper studies the temperature control measures and standards of dam concrete by using finite element method.Based on the calculation results of stable temperature field,the corresponding temperature control standards are proposed based on the specifications and similar projects.The sensitivity analysis of temperature control measures such as pouring temperature,cooling water and water pipe spacing is carried out by different schemes,and the recommended temperature control scheme is given.The simulation results show that the maximum temperature of each area cannot meet the control requirements without temperature control measures.The highest temperature is sensitive to the casting temperature,only when the casting temperature is controlled,the internal temperature drops slowly in the later stage,which may lead to the surface cracking due to the large temperature difference between inside and outside in the low temperature season.Considering the casting temperature and water cooling,the maximum temperature and temperature difference between inside and outside can be effectively reduced.The research results can provide reference for similar projects in subtropical region.