| 摘要: |
| 为完成青藏铁路多年冻土区桥梁钻孔灌注桩混凝土水化放热量的定量分析以及进一步确定持续低温环境下的混凝土水化放热计算模型，需要探究在持续低温环境下的混凝土水化放热情况.依照试验测定的数据计算出持续低温环境((3±1)℃,(8±1)℃,(13±1)℃)下水泥净浆的水化放热量随龄期增长的变化规律，结果发现：持续低温环境下水泥水化在各个龄期放出的热量以及水化程度都较水泥水化温度不受限制时有所减少，且持续低温环境的温度越低时，这一趋势越是明显；通过对试验数据的分析和拟合，得出了考虑不同持续低温环境对水泥水化放热计算模型影响的水化热计算模型，模型的计算结果不仅与实测数据吻合得较好，而且能较准确地预测在不同持续低温环境下水泥水化放热量随龄期的变化规律.该模型中各项参数物理意义明确，计算结果可靠实用，具有一定的推广应用价值. |
| 关键词: 水泥水化 水化放热 水化程度 持续低温 定量分析 计算模型 |
| DOI：103969/jissn1007 9629201502011 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(51268032)；长江学者和创新团队发展计划(IRT1139) |
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| Computing Model for the Hydration Heat of Cement Paste Considering the Effect of Sustained Low Temperature |
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WANG Qicai, CHEN Chuan, ZHANG Rongling, DUAN Yun
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School of Civil Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
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| Abstract: |
| The effect of sustained low temperature environment on the hydration heat of concrete was important for quantitative analysis of the hydration heat of concrete and for determination of the computing model for the hydration heat of concrete considering the effect of sustained low temperature of cast in place bored bridge piles in the construction of the Qinghai Tibet railway. The model was based on the monitored data to calculate the hydration heat of cement paste under the condition of sustained low temperature environment ((3±1)℃, (8±1)℃, (13±1)℃). Through experiments it is concluded that the hydration heat of cement paste under the condition of sustained low temperature environment is less than that of cement paste without any temperature limits, and this conclusion will be more obvious when the temperature of environment becomes lower. At last, through analysis of experimental data and the fitting to complete the computing model considering the hydration heat of cement paste under the condition of sustained low temperature environment, the results show that the model is in good agreement with the practice, and can be used to predict the hydration heat of cement paste under the condition of different sustained low temperature environment, in addition, it has some advantages such as simple formula, definite physical meaning and high accuracy, and it can be used to some applied engineering problems. |
| Key words: cement hydration hydration heat degree of hydration sustained low temperature quantitative analysis computing model |
