The effect of elevated temperature on self-compacting concrete: Physical and mechanical properties

¹ Department of Civil Engineering, GRIET, Hyderabad, India
² Department of Civil Engineering, CVR College of Engineering, Hyderabad, India
³ Department of Civil Engineering, VJIT, Hyderabad, India
⁴ Buliding and Construction Technical Engineering Department, College of Technical Engineering, The Islamic University, Najaf, Iraq
⁵ Uttaranchal School of Computing Sciences, Uttaranchal University, Dehradun 248007 INDIA

^* Corresponding author: madhavichalla2000@gmail.com

Abstract

Concrete’s thermal properties are more complex than for most materials because not only is the concrete a composite material whose constituents have different properties, but its properties also depend on moisture and porosity. Exposure of concrete to elevated temperature affects its mechanical and physical properties. In the current study, M40 and M80 grades of plain self-compacting concrete (SCC) mixes are developed using Nan Su mix design principles to investigate the effect of elevated temperatures on 1) weight and compressive strength 2) compressive strength of SCC when tested cool and hot 3) effect of 2, 4 and 6 hrs. exposure duration of elevated temperatures on compressive strength 4) modulus of elasticity 5) size of testing specimen and 5) effect of thermal cycles on SCC mixes. Results derived the following conclusions 1) the M80 specimens lose more strength than M40 SCC specimens when subjected to elevated temperatures ;2) specimens heated and then permitted to cool before testing lose more strength than those tested while hot; 3) the longer the duration of heating before testing, the larger the loss in strength; 4) The decrease in modulus of elasticity caused by elevated-temperature exposure is more pronounced than the decrease in compressive strength. 5) Small test specimens generally incur greater strength losses than larger ones and 6) Specimens subjected to several cycles of heating and cooling lose more strength than those not subjected to thermal cycling.