Scanning Electron Microscopic Evaluation of Self-Compacting Concrete Spalling at Elevated Temperatures

This paper reports the effect of addition of Polypropylene (PP) fibers in the performance of Self-Compacting Concrete (SCC) under elevated temperatures. Various SCC mixtures were made with PP fiber at 0.0, 0.05, 0.10 and 0.15% by volume added. The specimens were exposed to elevated temperatures (200°C [392°F], 400°C [752°F] and 600°C [1112°F]). The microstructure of the matrix was investigated. This study concluded that the high temperatures have a coarsening effect on the microstructure of SCC with the addition of PP fibers. It was reported that PP fibers reduced explosive spalling of SCC above 0.05% by volume and increased the number of voids in the microstructure significantly.

[1]  D. N. Crook,et al.  Regain of strength after firing of concrete , 1970 .

[2]  P. Jahren.  Fire Resistance of High Strength/Dense Concrete With Particular Reference to the Use of Condensed Silica Fume--A Review , 1989, "SP-114: Fly Ash, Silica Fume, Slag, and Natural Pozzolans in Concrete: Proceedings of the Third International Conference".

[3]  G. Peng,et al.  Change in microstructure of hardened cement paste subjected to elevated temperatures , 2008 .

[4]  V. Veiko,et al.  Laser-Assisted Microtechnology , 1998 .

[5]  Pierre-Claude Aitcin,et al.  Concrete structure, properties and materials , 1986 .

[6]  J. de Brito,et al.  Experimental study of the porosity and microstructure of self-compacting concrete (SCC) with binary and ternary mixes of fly ash and limestone filler , 2015 .

[7]  Fernando A. Branco,et al.  Effects of Formwork Fires in Bridge Construction , 1997 .

[8]  H. Toutanji,et al.  High-Strength Self-Compacting Concrete Exposed to Fire Test , 2006 .

[9]  Ulrich Schneider,et al.  Effect of temperature on steel and concrete for PCRV's , 1982 .

[10]  Albert Noumowe,et al.  Spalling, Thermal, and Hydrous Behavior of Ordinary and High-Strength Concrete Subjected to Elevated Temperature , 2011 .

[11]  A. Nazari,et al.  Microstructural, thermal, physical and mechanical behavior of the self compacting concrete containing SiO2 nanoparticles , 2010 .

[12]  F. C. Lea.  The Effect of Temperature on Some of the Properties of Metals , 1922 .

[13]  Naji M. Al-Mutairi,et al.  Assessment of Fire-Damaged Kuwaiti Structures , 1999 .