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 Vibration on Air Content of Mass Concrete
Author(s): Walter O. Crawley
Publication: Journal Proceedings
Appears on pages(s): 909-920
Keywords: no keywords
Abstract:Tests were made to observe the effect of high-frequency (13,000 vpm and moderate-frequency (6800 vpm) vibration on concrete ranging from 1/2 to 4-in. slump, containing 6-in. coarse aggregate, and having nominal air contents of 3, 6, and 9 percent in that portion of the mix smaller than the 1 1/2-in. sieve. Cores drilled from hardened specimens of the concrete with 6 percent air content were examined micrometrically for amount and distri-bution of air and coarse aggregate. The high-frequency vibrator was found to cause more rapid loss of entrained air than the moderate-frequency vibrator. However, either vibrator could cause a 50 percent loss in air from nominal 3 percent-air-content concrete in 30 sec. The rate at which air was lost generally increased with slump, but not to a marked degree. The high-frequency vibrator had more effect in causing movement, and escape of air, while the moderate-frequency vibrator caused more movement and segregation of the coarse aggregate.
Click here to become an online Journal subscriber