Mix Time and Retempering Studies on Ready-Mixed Concrete

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: Mix Time and Retempering Studies on Ready-Mixed Concrete

Author(s): Fred W. Beaufait and Peter G. Hoadle

Publication: Journal Proceedings

Volume: 70

Issue: 12

Appears on pages(s): 810-813

Keywords: compressive strength; failure; mix proportion- ing; mixing time; ready-mixed concrete; retempering; slump tests; water; water-cement ratio.

Date: 12/1/1973

Abstract:
This study is concerned with the extent of influence of mixing time and retempering on the compressive strength of ready-mixed concrete under field conditions. Three studies were conducted: (a) the first considered the effect of additional water on the compressive strength of concrete, (b) the second considered the effect of mixing time on the strength of concrete, and (c) the third considered the effect of both mixing time and retempering on the strength of concrete. The study was conducted using two different ready-mixed concrete mixes. The results of the study concluded that extended mixing does not adversely affect the compressive strength of the concrete until the concrete becomes impossible to work (slump equal zero). The retempering of the concrete mix does have an adverse effect on the strength of concrete. Concrete strength decreased as water was added, however, mixing appeared to increase the strength somewhat between periods of adding water.