Mechanical and durability related properties of high performance concrete made with coal cinder and waste foundry sand

The study of the mechanical behaviour and durability related properties of high-performance concrete (HPC) with additions of coal cinder (CC) and waste foundry sand (WFS) was presented in the paper. The following characteristics of the concrete were defined, i.e.: absorptivity, density, open porosity, contact angle, surface free energy (SFE), compressive strength, splitting tensile strength, flexural tensile strength, freezing-thawing resistance and salt resistance. The use of CC and WFS results in different wetting and adhesion properties of HPC. The total SFE was determined using the Neumann method. The smallest contact angle with water and the highest SFE, indicating increased wettability and increased adhesion properties, was obtained by the concrete with the highest addition of CC, due to the physical characteristics of this concrete. Based on the scanning electron microscope (SEM) investigation, the microstructure as well as distribution of cracks and pores in the concretes with waste materials were shown. Simultaneous action of the coal cinder and waste foundry sand improves resistance to salt crystallization. On the other hand freezing - thawing resistance is slightly worse.