OPTIMIZATION OF SELF-COMPACTING CEMENT ROAD CONCRETE ON THE CRITERIA OF THE MOBILITY OF THE MIXTURE AND COMPRESSIVE STRENGTH
Application of self-compacting concrete (SCC) in road construction provides improved quality of the road pavement, increased speed of construction, reduced energy consumption and laboriousness of the process. However, it is necessary to solve the conflicting rather complicated task - to provide high mobility (self-compactness) of concrete mix during the molding process, on the other hand - to provide the ability to retain the shape of fresh concrete without sedimentation immediately after extrusion of the slip-former (the thixotropic effect). The optimization of the formulation of SCC on the water-cement ratio value as well as the content of fine additive in the form of milled limestone (ML) has been done. To ensure the mobility of the concrete mix according to the data of spread diameter of standard cone within 310-370 mm and the concrete compressive strength not less than 55 MPa, the region of optimum formulations has to be in the range of: (W/C=0.449-0.425); (ML=15-33 %).