氧化钙对氯氧镁水泥低温凝结性能的影响

为了深入研究氯氧镁水泥低温凝结机理，进而改善和提高氯氧镁水泥在低温时的快硬性能，把氧化钙加入到氯氧镁水泥料浆中，通过搅拌、成型、恒温恒湿箱养护后测定其凝结时间及早期强度。结果表明：氧化钙加入后放出热量，引发氯氧镁水泥水化起始期反应的进行，有效缩短氯氧镁水泥的凝结时间。当氧化钙掺量为氧化镁质量的4%时，氧化镁活性为62.24%和72.01%时初凝时间分别由593 min缩短到146 min、由570 min缩短到126 min，终凝时间分别由673 min缩短到374 min、由641 min缩短到260 min，同时都提高了氯氧镁水泥的低温早期强度。

Effect of CaO on magnesium oxychloride cement setting performance at low temperature

The hardening mechanism was researched by adding CaO to magnesium oxychloride cement slurry，mixing，molding，and curing in a constant temperature and humidity chamber，determining the setting time and initial strength in order to improve and enhance the rapid hardening properties of the magnesium oxychloride cement at low temperature.Results indicated that：the reaction heat of CaO and H2O induced early reaction then shorten the setting time.When the mixing amount of CaO was 4%（mass fraction） of MgO，the initial setting time was reduced from 593 min to 146 min，the final setting time was reduced from 673 min to 374 min with magnesium oxide activity of 62.24%，and the initial setting time was reduced from570 min to 126 min，the final setting time was reduced from 641 min to 260 min with magnesium oxide activity of 72.01%，while the initial strength of magnesium oxychloride cement at low temperature were both increased.