蒸养制度对混凝土抗压强度的影响及其预测研究

Study of Steam-cured System Impact on Concrete Compressive Strength and Prediction of Strength Model

蒸养制度对混凝土强度具有十分重要的影响。测试了不同养护制度下获得的混凝土强度数据,分析了预养时间、升温速率和降温速率对混凝土出窑抗压强度和28d强度的影响;基于不同养护制度下混凝土出窑抗压强度和28d强度试验值,建立了混凝土出窑抗压强度和28d强度预测模型,模拟获得了其出窑抗压强度和28d强度,通过与试验数据对比发现预测模型是可靠的。研究结果都表明:延长预养时间、降低升温速率和降温速率,混凝土出窑抗压强度和28d强度提高;预养时间为3h、升温速率为2℃/10min和降温速率为3℃/20min时,混凝土出窑抗压强度和28d抗压强度达到最大值,是最佳蒸养制度。

Steam-cured system has an important impact on the strength of concrete. Concrete compressive strength under different steam-cured systems was tested. The influence of rest period, heating rate and cooling rate on concrete compressive strength out of kiln and 28 d strength were analyzed. Kiln strength and 28 d strength prediction models were established based on experimental data under different steam-cured systems. Kiln strength and 28 d strength were gained by prediction models, which was reliable by comparing simulation and experiment. Experiment and prediction models all show that： extending the rest period, reducing heating rate and cooling rate, kiln strength and 28 d strength will be increased; rest period lasting 3 h, heating rate at 2 ℃/10 min, and cooling rate at 3 ℃/20 min, kiln strength and 28 d strength reached the maximum, and this is best steam-cured systom