摘要:
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研究了不同水胶比m(w)/m(b)、浆体体积含量以及不同掺量与组合的矿物掺合料对混凝土自干燥引起自身相对湿度(autogenousrelative humidity,ARH)变化的影响,并从热力学角度探讨了高性能混凝土自干燥引起ARH变化的机理。研究表明,不同龄期下混凝土的ARH下降均随着m(w)/m(b)的减小而增大。混凝土中浆体体积含量越高,ARH下降越大。不同矿物掺合料因对混凝土水化进程与速率的影响不同,ARH下降也不同。水泥矿物继续水化引起毛细孔中可蒸发水含量下降是产生自干燥效应的主要原因。why women cheat on husbands link link
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Effects of m(w)/m(b) , paste volume content and mineral blends with different contents or combinations on autogenous relative humidity (ARH) change of concrete resulting from self-desiccation were studied. From the aspect of thermodynamics, mechanism of ARH change of high-performance concrete resulting from self-desiccation was discussed. The results indicate that ARH reduction of concrete increases with the decrease of m(w)/m(b) and the increase of paste volume content as well. The reduction of ARH varies also with the different influences on the ratio and process of hydration of concrete with different mineral blends. The reduction of evaporable water in capillary pores that mineral components caused by the continuous hydration is the main reason for self-desiccation.
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基金项目:
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国家973重大基础研究项目(2001CB610704);;同济大学工科基金
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作者简介:
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参考文献:
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