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冬期施工常用的混凝土养护法可分为两大类,一是在负温度下硬固,另一是在正温度下硬固。第一类是属于有化学抗冻剂的混凝土养护方法。第二类是除上述方法外其它所有的方法。化学抗冻剂(碳酸钾,硝酸钠,氯化钾)在苏联冬期施工的工程中用得相当普遍。现在已能使用化学抗冻剂融溶于拌合用水中,在低于-25℃温度下养护混凝土而不必加热。由此引起进一步研究十分有效的综合的抗冻剂(亚硝酸盐-硝酸钾,亚硝酸盐-硝酸盐-氯化钾,带有尿素-异尿素的硝酸钾等)。但是掺有抗冻剂的混凝土在负温下硬化很缓慢,需要六十昼夜或多于六十昼夜才能达到设计强度。
The commonly used concrete curing methods in winter construction can be divided into two categories: one is to harden at negative temperatures and the other is to harden at positive temperatures. The first category is concrete curing methods with chemical antifreeze. The second category is all but the above methods. Chemical anti-freeze agents (potassium carbonate, sodium nitrate, potassium chloride) are commonly used during Soviet winter construction projects. It is now possible to use chemical anti-freeze agents to dissolve in the mixing water and to cure the concrete at temperatures below -25°C without heating. This has led to further studies of effective antifreeze agents (nitrite-potassium nitrate, nitrite-nitrate-potassium chloride, potassium nitrate with urea-isourea, etc.). However, concrete mixed with anti-freezing agents hardens slowly at negative temperatures, requiring 60 days and more or more than 60 days to reach design strength.