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冬季施工常用的无加热浇筑混凝土方法是基于利用掺有多量抗冻剂的硅酸盐水泥。在-15℃条件下,最有效的外加剂K_2CO_3的掺量为12～15％(占水泥重量)。但这样可能发生碱腐蚀,降低混凝土的耐久性,提高成本,以致从经济上考虑,无加热的方法与蓄热法和电热法相比未必优越。冬季浇筑混凝土的实践表明,采用掺入有机矿物复合外加剂(含多量0.5～1％的表面活性物质和少量1～2％的碱金属的碳酸
The unheated cast concrete method commonly used in winter construction is based on the use of Portland cement mixed with a large amount of antifreeze. Under the conditions of -15°C, the most effective admixture of K_2CO_3 is 12 to 15% (in cement weight). However, alkali corrosion may occur, the durability of the concrete may be reduced, and the cost may be increased, so that the method without heating is not necessarily superior to the heat storage method and the electric heating method from the economical point of view. The practice of pouring concrete in winter has shown that it uses a mixture of organic mineral admixtures containing a large amount of 0.5 to 1% of surface active material and a small amount of 1 to 2% of alkali metal carbonate.