Publications

Concrete is the most commonly used material in the world for construction and to produce this large amount of concrete requires production of large quantities of cement which results in degradation of environment releasing harmful gases. One approach for making eco-friendly concrete is to use less cement in concrete, and for that aim, other cementitious materials can be utilized as a partial replacement for cement. This research focuses on the mechanical and durability properties of concrete having limestone powder (LSP) as a partial replacement for cement. Five different combinations are considered for this study and level of LSP replacement is 5%, 10%,15% and 20% (by weight). The result indicates that the slump value increases with increasing LSP content. At 28 days compressive strength and flexural strength are found the highest for a replacement of 10% cement with LSP. The concrete cylinders are subjected to elevated temperature (200°C and 400°C) for one hour and then cooled down to room temperature (25°C). Reduction in compressive strength with increased temperature is up to 6% at 200°C temperature and up to 11% at 400°C temperature. Chloride ion penetrability of LSP concrete is also performed using a surface resistivity meter. Penetrability of chloride ion is reducing with increased LSP content in concrete. Therefore, incorporating 10% LSP in concrete as a replacement of Portland cement will increase the mechanical and durability properties of concrete.

Over the last few decades, the global production of building materials has increased. Concrete is one of the highly used construction materials and in recent year different types of concretes are prevailing. Fly ash blended concrete with galvanized iron (GI) fiber is a type of concrete in which the cement can be partially or fully replaced by fly ash. This study investigates the influence of fly ash and GI fiber on the engineering properties of concrete by replacing different percentages of cement (5, 10 and 15 by weight) with fly ash and by adding 0.5% (by volume) GI fiber into the concrete. Workability, compressive strength, splitting tensile strength, flexural strength, stress strain response under axial compression, durability at high temperature are the engineering properties that have been investigated. It was found that concrete up to 15% fly ash and fiber showed better result of compressive strength than concrete without fly ash and fiber. The splitting tensile strength was also found to be highest in concrete with 15% fly ash and 0.5% fiber. The flexural strength of fiber reinforced concrete with fly ash has been examined by loading concrete beams. According to the findings, increasing the percentage of fly ash and adding GI fiber improved flexural strength and changed the stress strain response of fly ash blended concrete with GI fiber from brittle to ductile. The durability test results showed that higher percentages of fly ash decreased the strength reduction between compressive stresses at high temperature (500 °C) and room temperature (25 °C).