Concrete Q & A: Does Crushed Concrete Aggregate Meet Building Code and Specification Requirements? and Using Air Entrainment in the Caribbean

ABOUT THE 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.

International Concrete Abstracts Portal

  


Title: Concrete Q & A: Does Crushed Concrete Aggregate Meet Building Code and Specification Requirements? and Using Air Entrainment in the Caribbean

Author(s): Karthik Obla and Ward Malisch

Publication: Concrete International

Volume: 32

Issue: 8

Appears on pages(s): 75-76

Keywords:

Date: 8/1/2010

Abstract:
1. We’re considering having the concrete supplier use crushed concrete as coarse aggregate, and perhaps fine aggregate, in the 3000 psi (21 MPa) concrete specified for a project we’re building. Does aggregate produced by crushing returned concrete meet the requirements for aggregates in building codes and commonly used specifications? 2. We do most of our work in Canada, and we’ve become accustomed to using entrained air in our concrete to help protect it from freezing-and-thawing cycles. Because air entrainment also provides improved workability and decreased bleeding, we use it in most concrete—not just concrete exposed to freezing and thawing. Recently, one of our larger clients has asked us to work on a project in the Caribbean. The project includes a swimming pool near the ocean, and we’re considering using air entrainment for the pool and surrounding slabs.We know that air entrainment isn’t commonly used where the project is located. Even so, shouldn’t air entrainment be used in concrete that will be in constant or intermittent contact with dissolved chlorides or sulfates?