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摘要：
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综述了目前国内外混凝土抗裂能力评价计算模型,通过综合各方面影响因素,首次建立了混凝土抗裂能力分析模型,并考虑混凝土的经时变化,创建混凝土及其结构抗裂能力评价模型,用抗裂因子Kac作为评价混凝土抗裂能力的数学参数。选择具有代表性的混凝土配合比,分别计算了粉煤灰、矿渣、硅灰、膨胀剂、减缩剂、聚丙烯纤维组分的抗裂因子,通过数学计算得出的抗裂因子的大小顺序表明:粉煤灰、矿渣能够提高混凝土的抗裂因子,而硅灰则降低了混凝土的抗裂因子。掺加纤维、减缩剂、以及减缩剂和膨胀剂复合使用能够提高混凝土的抗裂性能,特别是减缩剂和膨胀剂复合使用能够大幅度提高抗裂因子,与大小圆环、平板法等各种约束开裂试验结果具有很好的一致性。而使用膨胀剂在早期养护不充分的前提下,有降低抗裂因子的趋势。
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This paper summarizes the calculation and evaluation model of anti-cracking ability of concrete at home and abroad.Through synthesizing the relevant factors,analysis model of anti-cracking ability of concrete is established for the first time,and meanwhile,considering the time-change of concrete,evaluation model of anti-cracking of concrete and its structure are es-tablished,and adopting Kac as mathematical parameter on anti-cracking performance of concrete.Choose representative con-crete mixture proportions,such as flying ash,blast furnace slag,silica fume,expansion agent,shrinkage-reducing agent,Polypropylene fibre etc.Kac of them are calculated respectively.It is concluded that FA,slag,fibre,SRA and SRA+EA can improve anti-cracking performance,but silica fume can decrease anti-cracking performance by comparison on Kac,and among them,whiling to use shrinkage-reducing agent and expansion agent with combination can promote effectively anti-cracking performance of concrete.The calculation results of Ka c are in according with that of restraint-cracking experiments such as big-small steel rings,flat-restraint.However,if the early curing of concrete is inadequate by using expansion agents,the trend of Kac maybe reduced.
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作者简介：
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参考文献：
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