Evaluation of Properties of Concrete Incorporating Ash as Mineral Admixtures

Cement industry has a huge environmental impact – it is responsible for a considerable part of man-made CO2 emissions. The prospective scenario to solve this problem is to substitute part of the cement clinker with industrial by-products or waste materials. In the present study coal ash and wood ash were used as a partial substitution of cement at 3 levels (20%; 30% and 40%) in concrete mixes. Ash was used in two ways – with no additional grinding and additionally ground for 30 minutes. Compressive strength of the hardened concrete samples was determined at the age of 7, 28, 56, 84 and 112 days. Ecological and economical characteristics of the materials were calculated.