Effect of Seashell Waste on Thermal and Mechanical Properties of High Strength Concrete

Abstract

Seashells are one of the numerous wastes that are quickly accumulating onshore coasts on the Arabian Sea, Karachi, Pakistan causing pollution for the environment. The seashell (SS) waste that causes various diseases and hazardous for environment can be used in concrete (0, 10, 20, and 30%) and in plastering mortar (20%, 40% and 60%) in place of fine aggregate to create an eco-friendly high strength concrete (HSC). Concrete materials undergo higher temperatures during their service period due to fire. After exposure to fire, properties of concrete have a prime importance in terms of serviceability of buildings and occupants’ safety. Therefore, to improve the fire resistant of high strength concrete, seashell waste was included, which is possibly a thermal degradable fiber. The mechanical properties namely compressive strength, stress-strain response, elastic modulus, compressive toughness, strain ductility and mass loss of modified and controlled samples, as well as the deterioration caused by elevated temperatures exposure were studied. The analyzed formulations were heated to a temperature of 200, 400, 600, and 800°C at a heating rate of 5°C/min and then tested for residual conditions. Seashell modified samples showed a higher compressive strength, elastic modulus, compressive toughness as compared to control sample at elevated temperature with less spalling sensitivity. According to visual inspection, SS-HSC as compared to HSC showed less cracking at higher temperatures. Moreover, the effect of plastering high strength concrete with seashell showed greater strength with more fire resistant to concrete core. Conclusively, utilization of seashell in high strength concrete is efficient for eco-friendly as well as fire resistant concrete.