大掺量矿渣石膏水泥基复合材料的水化特性

通过测试宏观抗压强度,同时采用XRD和TG-DTA技术对大掺量矿渣石膏水泥基复合材料的水化特性进行了研究,研究表明:大掺量矿渣石膏水泥基材料早期强度远低于纯水泥,但其强度发展较快,尤其是7～28 d阶段,28 d强度基本达到42.5 MPa水平,90 d龄期强度除SG-4试件均超过纯水泥水平.试件早期强度随着熟料含量的增加而增长,而后期强度并不遵循这一规律,水化后期主要是矿渣粉中活性Al2O3与活性SiO2参与水化反应,提高了体系抗压强度.SG系列水化产物主要为C-S-H凝胶和AFt,而纯水泥试样有大量Ca(OH)2而几乎无AFt存在.熟料含量对早期水化产物数量影响较大,而对水化产物种类及水化后期产物数量影响不大.

Hydration Characteristics of Cement-based Material Containing High-volume Slag and Gypsum

The hydration characteristics of cement-based material containing high-volume of slag and gypsum(SG)were studied by testing compressive strength,using XRD and TG-DTA technology.The results show that the early strength of SG is far lower than that of ordinary Portland cement(C),while the strength development is very fast especially at the stage of 7-28 d.The strength at 28 d reaches to the level of 42.5 MPa and the strength of SGs except for SG-4 paste at 90 d are higher than that of C.With the increase of clinker content,early strength of SGs increase,while no follow the rule on later-age strength.In later hydration age,active Al2O3 and active SiO2 in slag powder participate in the reaction and improve the compressive strength.Hydration products of SGs is mainly for C-S-H gels and AFt,there is a large amount of Ca(OH)2 replaced of AFt in C.Clinker content has great influence on hydration product quantity,while little effect on the kinds of hydration products and hydration product quantity in later-age.