Influence of Recycled Concrete Composition on Its Elastic Stiffness

摘要

The presented study was focused on the influence of the micronized recycled a concrete sleeper on the mechanical properties of fine-grained concrete, specifically on dynamic modulus of elasticity. The tested material consisted of cement CEM I 42.5R (Radotin), crushed bricks fraction 2-5 mm, 0-4 mm sand and micronized recycled concrete fraction 0-0.125 mm. Individual material samples differed in the quantity of cement and finely ground recycled concrete (milled at Ltd. Lavaris, Libclee - Czech Republic). Cement was replaced by the recycled concrete in an amount of 30, 50 and 70 weight percent. Testing was performed on beams of dimensions 40× 40× 160 mm by using non-destructive testing - pulse method. The article compares the values obtained between 2-nd and 28-th day.