Fast-Track Construction with Slag Cement Concrete
ACI MATERIALS JOURNAL
TECHNICAL PAPER
Title no. 104-M43
Fast-Track Construction with Slag Cement Concrete:
Adiabatic Strength Development and Strength Prediction by Stephanie J. Barnett, Marios N. Soutsos, John H. Bungey, and Steve G. Millard
The early-age strength development of concrete containing slag cement has been investigated to give guidance for its use in fasttrack construction. Measurements of temperature rise under adiabatic conditions have shown that high levels of slag cement— for example, 70% of the total binder—are required to obtain a significant reduction in the peak temperature rise. Despite these temperature rises being lower than those for portland cement mixtures, however, the early-age strength under adiabatic conditions of slag cement concrete can be as high as 250% of the strength of companion cubes cured at 20 °C (68 °F). The maturity and, hence, strength development were calculated from the adiabatic temperature histories based on several maturity functions available in the literature. The predicted strength development with age was compared with the experimental results. Maturity functions that take into account the lower ultimate strengths obtained at elevated curing temperatures were found to be better at predicting the strength development.
Keywords: early age; fast-track construction; slag cement; strength.
INTRODUCTION
In recent years, fast-track construction has created a need for early-age estimates of concrete strength. Fast-track construction can have considerable economic benefits.
Accelerated construction schedules that put a new, repaired, or overlaid pavement into service require adequate concrete strength to withstand traffic loads. Typical applications include localized repairs, replacement of busy intersections, and major slipform paving. In structural components, the early removal of forms or the application of post-tensioning and the termination of curing in cold weather have
TECHNICAL PAPER
Title no. 104-M43
Fast-Track Construction with Slag Cement Concrete:
Adiabatic Strength Development and Strength Prediction by Stephanie J. Barnett, Marios N. Soutsos, John H. Bungey, and Steve G. Millard
The early-age strength development of concrete containing slag cement has been investigated to give guidance for its use in fasttrack construction. Measurements of temperature rise under adiabatic conditions have shown that high levels of slag cement— for example, 70% of the total binder—are required to obtain a significant reduction in the peak temperature rise. Despite these temperature rises being lower than those for portland cement mixtures, however, the early-age strength under adiabatic conditions of slag cement concrete can be as high as 250% of the strength of companion cubes cured at 20 °C (68 °F). The maturity and, hence, strength development were calculated from the adiabatic temperature histories based on several maturity functions available in the literature. The predicted strength development with age was compared with the experimental results. Maturity functions that take into account the lower ultimate strengths obtained at elevated curing temperatures were found to be better at predicting the strength development.
Keywords: early age; fast-track construction; slag cement; strength.
INTRODUCTION
In recent years, fast-track construction has created a need for early-age estimates of concrete strength. Fast-track construction can have considerable economic benefits.
Accelerated construction schedules that put a new, repaired, or overlaid pavement into service require adequate concrete strength to withstand traffic loads. Typical applications include localized repairs, replacement of busy intersections, and major slipform paving. In structural components, the early removal of forms or the application of post-tensioning and the termination of curing in cold weather have
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