Finite element modeling of hydration heat in a concrete slab-on-grade floor with limestone blended cement
Finite element modeling of hydration heat in a concrete slab-on-grade floor with limestone blended cement
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DOI：
10.1016/j.conbuildmat.2017.07.176
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发表时间：
2017-11
影响因子：
7.4
通讯作者：
Mohammad H. Tahersima;P. Tikalsky
中科院分区：
文献类型：
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作者：
Mohammad H. Tahersima;P. Tikalsky
大体积混凝土结构中的延迟钙矾石形成和温度裂缝是两个主要的温升问题。石灰石、水泥、粉煤灰大体积混凝土的水化热存在差异，商业软件不能很好地预测。本研究的目的是为设计人员或软件开发人员提供此类数据。在这项研究中，热电偶测量在施工现场的结果进行了比较，广泛使用的商业有限元模型（FEM）和广泛使用的混凝土设计软件包。用ASTM C595 I型石灰石混合水泥（IL）取代25%的ASTM C618 C型粉煤灰（FC）质量，用实验数据完成了有限元法的验证。本研究采用相同的工地配合比设计，模拟足尺建筑物的水化热。预测了Ⅰ-Ⅱ型水泥、25%FC水泥和IL型水泥的水化热，比较了不同配合比的水化热结果。与商品混凝土软件计算结果相比，有限元计算结果与施工现场数据具有更好的一致性。有限元结果的预测精度为15%以上的最大温升和30%以上的峰值时间。IL型水泥比I-II型水泥具有更大的水化热。准确预测水化热的两个主要因素是应用环境温度和量热法的测量结果。
Delayed ettringite formation and thermal cracks are two main concerns of temperature rise in mass concrete structures. The mass concrete containing limestone blended cement and fly ash has different hydration heat that was not well predicted by commercially available software. The purpose of this study is to provide such data for designers or software developers. In this study, results of thermocouple measurement at the construction site are compared with a widely used commercial finite element model (FEM) and a widely used concrete design software package. Verification of the FEM with experimental data has been completed with cement ASTM C595 Type I limestone blended cement (IL) with a 25% replacement by mass of ASTM C618 Type C fly ash (FC). In this study, the same mixture design of construction site was used in modeling of hydration heat of full scale building. The heat of hydration for cement Type I-II and 25% of FC and cement Type IL are predicted to compare the results of hydration heat generated by different mix proportions. The FEM result has a much better compatibility with the construction site data with respect to the commercial concrete software results. The prediction accuracy of finite element results is about 15% more for the maximum temperature rise and 30% more for the peak time. Cement Type IL has greater hydration heat than cement Type I-II. Applying measured ambient temperature and calorimetry results are two main factors in precise prediction of hydration heat.