低热水泥胶凝体系水化热计算研究

Study on hydration heat calculation of cementing system of low heat cement

为了评价几种传统水化热计算方法对低热水泥的适用性,进而提出低热水泥胶凝体系水化热的计算公式,采用直接法测定了不同掺量粉煤灰、矿渣条件下的低热水泥胶凝体系7 d水化热,对比应用矿物成分法、折算公式法、数值拟合法算得相应结果,调整各模型参数并对其计算精度进行评价分析。研究结果表明:矿物成分法仅能计算特征龄期下水泥水化热,算得结果与试验数值差距较大;折算公式法用于计算单一掺合料下胶凝材料7 d水化热时所得结果准确度较高;数值拟合法适用于单掺、复掺不同掺量矿物掺合料的低热水泥胶凝体系,该体系下粉煤灰、矿渣的最终水化热分别为126.6 J/g和172.4 J/g。研究成果可为大体积混凝土的绝热温升计算提供基础数据参考。

In order to evaluate the applicability of several traditional hydration heat calculation methods to cementing system of low heat cement and propose a new calculation formula,hydration heat of low heat cement on 7th day with different amount of fly ash and slag is measured by direct method.Then the results from mineral component method,conversion formula method and numerical fitting method are compared with that of direct method,in which the parameters of different methods are adjusted and their applicability is evaluated.Research results show that mineral component method can only calculate hydration heat of characteristic age cement and the calculated result is far different from the experimental result;conversion formula method is proper for the hydration heat on 7th day calculation of single admixture cementing material;numerical fitting method is applicable to the low heat cement cementing system with different amount of fly ash and slag,whose final hydration heats are 126.6 J/g and 172.4 J/g respectively.The research results can provide basic data reference for the calculation of adiabatic temperature rise of mass concrete.