摘要
混凝土绝热温升计算模型是影响混凝土结构水化热温度场有限元仿真分析精度的关键因素.本文从水泥水化放热反应本质出发,考虑龄期、温度和温度历史影响,提出了一种基于水泥水化度的混凝土绝热温升计算模型.通过对混凝土绝热温升试验数据的拟合,确定模型特征参数及验证模型的准确性,并将模型应用于混凝土温度场有限元仿真分析中.算例结果表明,该模型不仅能够采用统一的函数来描述不同浇筑温度和温度历程下的绝热温升过程,且与混凝土绝热温升的试验实测数据较好吻合,同时也能较精确地预测工程现场条件下混凝土结构实际的温度变化,具有一定的应用价值.
The model of adiabatic temperature rise of concrete is the crucial factor for influencing temperature distribution calculated by FEM simulation.On the basis of the essence of hydration and heat generation of concrete,a new calculation model of adiabatic temperature rise was proposed,which was based on the degree of hydration,and took the effect of age,temperature and its thermal history into account.By adiabatic temperature test data regression analysis,parameters of the model were determined and the rationality of the model was also verified.Then,the model was applied in FEM analysis.Numerical simulation results indicate that the model can not only describe the temperature-time relationship under different curing temperature and thermal history with a uniform function,but also give more accurately estimate of temperature variation in concrete structure under engineering conditions.Thus,the proposed model has some actual value.
出处
《应用基础与工程科学学报》
EI
CSCD
2011年第2期243-250,共8页
Journal of Basic Science and Engineering
基金
国家自然科学基金重点资助项目(505790805077901050539010)
关键词
混凝土
水化度
绝热温升
等效时间
有限元方法
concrete
degree of hydration
adiabatic temperature rise
equivalent time
finite element method
