In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Become an ACI Member
Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
American Concrete Institute
38800 Country Club Dr.
Farmington Hills, MI
Feedback via Email
Home > Publications > International Concrete Abstracts Portal
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.
Title: Effect of an Alkaline Set Accelerator on Normal Portland Cement Paste in the Presence of a Superplasticizer
Author(s): Q Xu, C. Roessler, J. Stark, and P. Wang
Publication: Special Publication
Appears on pages(s): 409-422
Keywords: accelerator; calcium aluminate hydrate; ettringite; heat release; hydrate phases; hydration; pore solution; set time; superplasticizer
Abstract:The effect of an alkaline set accelerator on the setting of the cement paste without and with a superplasticizer is compared. The results show that the presence of the superplasticizer weakens the effect of the set accelerator. In order to attain the demanded rapid setting a higher content of the accelerator is needed. The early hydration process of the cement is largely changed by the two admixtures. It can be shown that the superplasticizer restrained the formation of the calcium aluminate hydrate phases whereas the accelerator increases the rate of formation of the calcium aluminate phases in the paste. Furthermore, due to superplasticizer-accelerator interaction the morphology of the calcium aluminate hydrate phases is changed. The calcium aluminate hydrate phases precipitate as clusters with a spheroid shape. We state that the cluster formation of the calcium aluminate hydrate phases is the reason for the reduced acceleration of the setting of the superplasticizer/accelerator containing paste.
Click here to become an online Journal subscriber