Mechanical and Flexural performance of Reinforced Concrete Beams with Calcined Kaolin as Partial Cement Replacement

Abstract

Different researches have been carried out using calcined kaolin (CK) as a pozzolanic material to replace cement in concrete to reduce its effect on green gas emissions and raw materials consumption. However, in terms of mechanical properties of concrete and load carrying capacity of structural members, the results of the researches vary despite being very few to offer a specific conclusion. Keeping in mind that bending and shear behaviour are of concern to civil and structural engineers as bending could result in sudden and catastrophic failure. The main objective of this study is to investigate the mechanical and flexural performance behavior of reinforced concrete (RC) beams with kaolin calcined at 700˚C as partial cement replacement under four-point bending test. The physical properties and mechanical properties of control and concrete with CK in the proportion of 0% to 30% by weight of cement were determined. Six beams designed in accordance to Eurocode 2 with predetermined dimensions of 1800 mm × 150 mm × 200 mm, shape, number and size of steel bars and concrete grade of 30 MPa with a mix ratio of 1:1.55:2.75 and water-cement ratio of 0.54 were used. The optimum dosage of CK obtained from the compressive strength of the modified concrete to use in beams was found to be 20%. It was observed that initial crack load, failure load, deflections and crack patterns and failure modes of the beams were comparable to control beams which is a valuable insight for structural applications of CK.