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.
DOI:
10.14359/7146
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.