Impact Resistance and Mechanical Properties of Optimized SCC Developed with Coarse and Fine Lightweight Expanded Slate Aggregate

Abstract

This study evaluated the impact resistance and mechanical properties of a number of optimized self-consolidating concrete mixtures developed with lightweight expanded slate aggregate. The investigated parameters included different lightweight expanded slate types (fine and coarse), different aggregate volumes, and various binder contents (500, 550, and 600 kg/m3). The mechanical properties of all developed mixtures were assessed using the compressive strength, splitting tensile strength, flexural strength, and modulus of elasticity. On the other hand, the impact resistance for the tested mixtures was evaluated by a drop-weight test conducted on both cylinders and small-scale prism beams. The results showed that despite the relatively low strength of lightweight aggregates, using a ternary binder material system (cement, metakaolin, and fly ash) helped to develop successful lightweight self-consolidating concrete mixtures with a density ranging from 1,850 to 2,000 kg/m3 and a strength of at least 50 MPa. Expanded slate fine aggregate showed better mechanical properties and impact resistance when compared to expanded slate coarse aggregate. The results also indicated that with the absence of self-compactability restrictions, it was possible to develop LWVC mixtures, with a density of up to 1,784 kg/m3 and compressive strength of around 40 MPa.