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

Showing 1-2 of 2 Abstracts search results

Document: 

108-M03

Date: 

January 1, 2011

Author(s):

Sam Slatnick, Kyle A. Riding, Kevin J. Folliard, Maria C. G. Juenger, and Anton K. Schindler

Publication:

Materials Journal

Volume:

108

Issue:

1

Abstract:

Autogenous shrinkage, significant primarily in concretes with a low water-cementitious material ratio (w/cm), has received more attention in recent years due to the increasing use of high-performance concretes (HPCs). In this study, autogenous shrinkage was quantified in both unrestrained and restrained concrete. The specimens were sealed and kept at a constant isothermal temperature of 20°C (68°F) to prevent deformation due to temperature change or moisture loss. Various materials were evaluated to compare their effectiveness in reducing autogenous deformation and stress development, including saturated lightweight aggregates, shrinkage-reducing admixtures (SRAs), and a shrinkage-compensating additive (based on calcium sulfoaluminate). The data obtained also provide insight into the mechanisms behind autogenous shrinkage and the resulting stress development in restrained members and quantify the effects of methods used to reduce autogenous shrinkage and the resultant stresses.

DOI:

10.14359/51664212


Document: 

104-M69

Date: 

November 1, 2007

Author(s):

Michael D. Brown, Cuyler A. Smith, J. Greg Sellers, Kevin J. Folliard, and John E. Breen

Publication:

Materials Journal

Volume:

104

Issue:

6

Abstract:

According to a survey conducted in 1996, respondents in several state departments of transportation indicated that more than 100,000 bridge decks in the U.S. have suffered from early age transverse cracking, a crack pattern that typically arises due to drying shrinkage. Concrete material properties are treated as a means through which to improve the resistance restrained drying shrinkage cracking. Various test methods are discussed as they relate to determining the resistance of a material to shrinkage cracking. Materials-based methods of controlling drying shrinkage are presented. The materials discussed include fibers, shrinkage-compensating concrete, shrinkage-reducing admixtures, and extensible concrete. It was determined in small laboratory specimens, and confirmed in large-scale bridge deck specimens, that several of the alternative mixtures adequately reduced restrained drying-shrinkage cracking.

DOI:

10.14359/18967


Results Per Page