水泥粒径分布对混凝土绝热温升影响的模拟

摘要

为了模拟水泥粒径分布对混凝土绝热温升过程的影响,建立了一个基于水化深度的水化模型.该模型假定混凝土中水泥水化过程由水化深度控制,且水化深度随时间的发展与颗粒粒径无关;通过水泥等温放热曲线试验推导得出最大水化深度的存在;假定温度对水化过程的影响满足Arrhenius公式.通过混凝土绝热温升仪测定了3种不同初始温度下的绝热温升曲线,以此得到水化模型所需的基准水化速率曲线.最后将建立的水化模型用于模拟混凝土的绝热温升曲线,结果表明：基于水化深度的水化模型能够准确模拟水泥粒径分布和初始温度对混凝土绝热温升的影响.%To simulate the effects of cement＇s particle size distribution on the adiabatic temperature rise of concrete,a hydration model based on hydration depth was built.In this model,the hydration process of cement in concrete was assumed to be controlled by the hydration depth,which was independent of cement particle size;Based on the experimental results of isothermal hydration heat of cement,the maximum hydration depth was deduced;The effects of temperature on the hydration process was assumed to be simulated by the Arrhenius law.The reference hydration rate curve was derived from the adiabatic temperature rises of concrete at three different casting temperatures,which were examined by the adiabatic temperature rise equipment.At last,the model was applied to simulate the adiabatic temperature rise of concrete in the experiments.The results show that the hydration model based on the hydration depth can simulate the effects of cement＇s particle size distribution and casting temperature on the adiabatic temperature rise of concrete with satisfactory accuracy.