Evaluation of Grade 120 Granulated Ground Blast Furnace Slag in Concrete (Grade211 120)

摘要

This study evaluates Grade 120 Granulated Blast Furnace Slag GGBFS and its effect211u001eon the properties of hydraulic cement concrete used in structural and pavement 211u001econstruction. Several mix designs, structural and pavement, were used for this 211u001eevaluation with varying amounts of GGBFS used as a substitution for cement. These 211u001esubstitutions were a percentage by weight substitution. This study looked at the 211u001eeffects of slag on workability, constructability, durability and the compressive 211u001estrength of the concrete. How GGBFS affected the concrete's set times was also 211u001ecritical in establishing the maximum substitution amount for LADOTD concrete 211u001estructures and pavements. In addition, an informal telephone survey was taken 211u001ewith other state DOT's concerning their use and experience using GGBGS in 211u001econcrete. This further assisted LADOTD in the development of their own 211u001especifications for GGBFS concretes. Test results indicate that concretes with 211u001eGGBFS substitutions displayed delays in set times and exhibited delays in 211u001ecompressive strengths at an early age, as compared to conventional concrete 211u001emixes. However, at later ages the compressive and flexural strengths markedly 211u001esurpassed those of conventional concrete mixes as compared to conventional 211u001econcrete mixes. However, at later ages the compressive and flexural strengths 211u001emarkedly surpassed those of conventional mixes as the cement content increased. 211u001ePermeability was greatly reduced in those concretes that incorporated GGBFS as 211u001eopposed to the conventional mixes.