EFFECT OF FIRE ON THE COMPRESSIVE STRENGTH OF CONCRETE

Abstract

ABSTRACT This project examines the effect of fire on the compressive strength of concrete. Fifty Four (54) concrete cubes were casted, cured for twenty eight (28)days and six (6) cubes for each level of temperature were su~ected to various range of temperature (ambient temperature, 50°c, 100°c, 150°c, 200° , 250°c, 300°c 350°c, and 400°c) for one hour and crushed, concrete materials/mix, curing and all test kept constant. Mix ratio used was 1:2:4 and water cement ratio adopted was 0.50. Average strength for each temperature level was taken and it was noticed that concrete retained its integrity as a load bearing element when subjected to temperature up to 300°c, beyond which the compressive strength start falling. Concrete strength after twenty eight (28) days curing under normal room temperature was retained even when subjected to 50°C and 100°c for one hour each. Beyond this temperature the concrete compressive strength increases (when subjected to 150°c, 200°c, 250°c and 300°c ). The strength start falling when 300°C was exceeded to 350°C and 400°C This shows that concrete strength will be retained if exposed to a typical fire/temperature