Effect of elevated temperature on Stress-Strain behaviour of Self-Compacting concrete

Abstract

Self-Compacting Concrete (SCC) is an emerging building material as it has unique benefits over conventional concrete. SCC is a High-Performance Concrete (HPC) having the filling ability, passing ability and segregation resistance. In addition, SCC does not require vibration. However, to develop SCC, an appropriate mix design has to be carried out following EFNARC guidelines. This paper attempts to develop a design mix proportion for grades of SCC such as M25, M30, M35, and M40. The requirements of fresh SCC are validated with appropriate experiments such as the V-funnel test, J-ring test, and slump flow test. Cube compressive strength of different grades of hardened SCC was validated at 28 and 56 days. The other mechanical properties, such as tensile strength, flexural strength, and modulus of elasticity, were also examined for different grades of SCC, and the test results are reported. Fire-resistance of building materials has to be assessed to ensure the fire safety of humans and infrastructure during the event of fire accidents. Stress–strain curves were developed to characterize the behaviour of different grades of SCC under elevated temperatures. Three stages of elevated temperatures, such as 300, 600, and 900 °C with two methods of heating, were considered in this experimental investigation. It was observed that the maximum stress capacity of SCC linearly decreases with respect to the elevated temperature. Also, the peak strain of different grades of SCC increased as the exposure temperature increases. The changes in the ductile property of different grades of SCC are found to be quantitatively evaluated in terms of Energy Absorption Capacity (EAC). The EAC values are found to be decreased when the exposure temperature increases.