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一、前言普通水泥在低于0℃的环境下使用是十分困难的,而在-15℃下欲获得较高的初始强度和最终强度更不可能。试验证明,在-15℃下普通水泥浆体在初凝前就几乎完全冻结。解决负温下固化问题的常用方法是在工艺上采用保温法;此外还可采用早强水泥或掺加负温外加剂。掺用LS—AC复合外加剂制备低温水泥不仅降低了冰点,而且因其本身高效减水导致水泥石孔结构的改善——特别是过渡孔孔
I. INTRODUCTION It is very difficult to use ordinary cement in environments below 0°C, but it is less likely to obtain higher initial strength and final strength at -15°C. Tests have shown that the ordinary cement slurry freezes almost completely before the initial setting at -15°C. A commonly used method for solving the problem of curing at negative temperature is to adopt a heat preservation method in the process; in addition, it is also possible to use early-strength cement or add a negative temperature additive. The addition of LS-AC composite admixture to prepare low-temperature cement not only reduces the freezing point, but also improves the pore structure of the cement stone due to its high water-reducing efficiency - especially the transition pores.