外加剂对贝利特-硫铝酸盐水泥凝结时间及水化的影响

Effects of several chemical additive on the setting time and hydration of belite-sulfoaluminate cement

研究三乙醇胺(TEA)、三异丙醇胺(TIPA)与聚羧酸对贝利特-硫铝酸盐水泥凝结时间及水化的影响。通过对其凝结时间、力学性能、水化产物、孔径分布的表征确定最佳的外加剂种类和数量。结果表明:3种外加剂对水泥有不同程度的缓凝效果,其中聚羧酸缓凝效果最为显著。聚羧酸掺量达0.075%时,初凝与终凝时间分别可延至126和182 min;同时聚羧酸的加入降低了1与3 d强度,提高了28 d强度。水泥强度除与水化产物的种类、含量有关外,还与水泥浆体中孔径分布有关。

Effects of triethanolamine（ TEA）,triisopropanolamine（ TIPA） and polycarboxylate superplasticizer on the setting time and hydration of belite-sulfoaluminate cement were investigated. The best type and quantity of admixture was determined by the characterization of setting time,mechanical properties,hydration products,and pore size distribution. Results indicated that three kinds of admixture had different effects on the setting time,and polycarboxylate superplasticizer had the best retarding effect.In the presence of 0. 075% polycarboxylate superplasticizer,the initial time and final setting time were126 and 182 min,respectively. The effects of the superplasticizer on the strength development at different hydration stages presented different results,observed by a decreased strength at early stage（ 1 d and 3 d）and increased strength at 28 d. It was also showed that the strength of cement was related to the type and quantity of admixture and the pore size distribution.