Engineering properties of artificial fly ash aggregate with various geometric characteristics

Abstract

This paper focuses on investigating engineering properties of artificial fly ash aggregate (FAA) with two geometric characteristics produced through two production methods, including a cold-bonded technique (V-FAA) and a manual crushing method (Đ-FAA), to expand application of FAA in the production of concrete. With the purpose of reusing a large amount of fly ash (FA), FAA was produced from 85% FA and 15% cement, a water-to-binder ratio of 20%. After the forming process, FAA with particle sizes ranging from 12.5 – 20 mm was cured in water before testing engineering properties. In addition, the engineering properties of crushed stone (CS) were determined for comparison purposes. The engineering properties of the aggregates investigated included density, bulk density, water absorption, and crushing value. Experimental results showed that V-FAA with smooth and round particles and Đ-FAA having angular shapes had lower engineering properties than CS. The extended curing time contributed to slightly improving the engineering properties of both V-FAA and Đ-FAA. When compared with V-FAA with smooth and round particles, Đ-FAA having angular shapes exhibited enhanced engineering properties. Relationships between engineering properties of aggregates were established. Consequently, the engineering properties of FAA depend on geometrical characteristics orginating from various production methods.