LABORATORY-MADE ROLLER COMPACTED CONCRETES CONTAINING DRY BOTTOM ASH: PART 1- MECHANICAL PROPERTIES

The behavior of laboratory-made roller compacted concretes (RCC) containing pulverized coal combustion high-calcium dry bottom ash as a fine aggregate was investigated. Standard concrete samples of nine different mixture proportions (cement contents ranging from 9% to 15%, and coarse aggregate contents of 50%, 55%, and 60% by mass of total dry solids) were prepared at the optimum moisture content and consolidated in accordance with the requirements of ASTM C 1170, Procedure A. The concrete specimens were water-cured at different ages, up to 6 months. This paper presents the fresh properties and strength, stiffness, and deformation characteristics of hardened bottom ash roller compacted concretes. Test results conclude that RCC samples containing dry bottom ash offer excellent strength, stiffness, and deformation properties, considering the range of cement factors used. For the mixtures under investigation, the compressive strength, splitting-tensile resistance, flexural strength, and modulus of elasticity varied from 2,439 to 7,222, 374 to 726, 567 psi to 1,103 psi, and 3,033 ksi to 5,539 ksi, respectively. The year-old drying shrinkage strain ranged between 0.000203 and 0.000298.