A New Mix Design Methodology for Roller Compacted Concrete, with Case Studies

A new mix design methodology for roller compacted concrete (RCC) is described that involves preparing low and high density specimens at various (typically three) cement contents. For each specimen density is determined. Strengths (compressive and/or split tensile) are measured at various intervals (e.g., 1, 4, 7 and 28 days). Multiple linear regression analysis of the data results in equations of the form: log S = a0 + a1 log D + a 2 log C + a3 log I in which S = strength, D = density, C = cement content, T = time Equations with excellent fit to the data were developed for three aggregates used in actual practice, and field sample results verified the methodology. Similar equations were developed for RCC made from recycled portland cement concrete and asphalt concrete. An additional term (-a 4 log F) accounted for the ratio (F) of AC:PCC in the blend.