摘   要：通过对聚合硫酸铝进行改性，研制出一种无碱液态高效水泥速凝剂。研究结果表明，当速凝剂掺量为5%时，可使P·O 42.5级水泥的初凝时间缩短至2min48s，终凝时间缩短至4min37s，1d抗压强度达到8.6MPa，1d、28d抗压强度和抗折强度保留率分别为79.63%、81.89%和78.13%、97.89%。采用XRD、DSC测试手段对水泥的水化样进行分析，探讨了这种速凝剂的速凝机理。

Abstract: A kind of non-alkali high efficiency liquid cement setting accelerator is developed by regulating the chemical composition of polymerized aluminum sulfate. The results show that the initial setting time and the final setting time are sharply shortened to 2 minutes 48 seconds and 4 minutes 37 seconds respectively and the 1d compressive strength reaches to 8.6MPa when the dosage of the setting accelerator is 5%. Meanwhile, its compressive strength and flexural strength retention at the age of 1d and 28d reach to 79.63%、81.89% and 78.13%、97.89% respectively. Phase characteristics on the hydrated cement specimens by means of XRD and DSC are analyzed and the acceleration mechanism is discussed.