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
Chat with Us Online Now
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: Influence of Storage Conditions and Concrete Composition on the Effectiveness of Different Silica Fumes Against ASR
Author(s): M.A. Berube, J. Duchesne and J. Frenette
Publication: Special Publication
Appears on pages(s): 1127-1147
Keywords: alkali-silica content; alkali-silica reaction; cement paste; concrete; high
performance concrete; silica fume: temperature.
Abstract:Cement paste samples incorporating various amounts of silica fume were made and stored in humid air at 23°C and 38°C. Their pore solution was expressed under high pressure at different times, then analyzed for its alkali content. The storage temperature did not significantly affect the alkali concentration in the short term (O-28 days), where most reaction products (hydrates) are formed. However, all control and blended pastes stored at 38°C recycled very significant amounts of alkali in the pore solution between 28 days and 1.5 years, while not those stored at 23°C. Consequently, the longter effectiveness of silica fume against ASR should be better than expected from a number of recent experimental studies all involving concrete expansion tests conducted at 38°C for field concretes exposed at an average lower temperature, e.g. in many regions of the world. This would explain at the same time why satisfactory field performance is reported in Iceland, for instance, while the only one case reported until now relating to poor field performance of silica fume against ASR took place under the hot South African climate. Results from concrete prism expansion tests also indicated that ASR expansion can develop in high-performance concrete, even with moderately reactive aggregates. Other expansion results confirmed that the higher the degree of reactivity of the particular reactive aggregate to counteract, the alkali content in the silica fume, the alkali content in the portland cement used, and the cement dosage, in other words the higher the total concrete alkali content, the higher is the amount of silica fume required to counteract ASR expansion. The study also indicated that pelletizing the silica fume before mixing with the clinker at the grinding stage did not reduce its effectiveness against ASR, provided the grinding process is effective in dispersing the silica fume.
Click here to become an online Journal subscriber