Study on mechanism of thermal spalling in concrete exposed to elevated temperatures

This paper presents a review of explosive spalling of concrete at elevated temperatures. The affecting factors, mechanisms and current theoretical and experimental studies are summarized. Using a numerical model proposed by the authors, numerical simulations were performed to investigate the effects of the thermally cracking process considering the effects of heterogeneity of the material properties on the spalling in concrete exposed to a transient thermal load. The investigations showed that the thermal cracking is the key factor causing the corner and surface spalling, and suggested that a coupling of thermal cracking and pore pressure is the main cause of explosive spalling and uncertainty of explosive spalling. The explosive spalling induced by elevated temperatures is a complex nonlinear problem, which can be understood only through establishing a methodology using behavioral aspects for both material science and mechanics.

[1]  Chi Sun Poon,et al.  Experimental study of micro/macro crack development and stress-strain relations of cement-based composite materials at elevated temperatures , 2004 .

[2]  Kristian Dahl Hertz,et al.  Limits of spalling of fire-exposed concrete , 2003 .

[3]  Daniel Quenard,et al.  Spalling and pore pressure in HPC at high temperatures , 2000 .

[4]  B. Schrefler,et al.  Modelling of heated concrete , 2002 .

[5]  Wei-Ming Lin,et al.  Microstructures of Fire-Damaged Concrete , 1996 .

[6]  G Sanjayan,et al.  SPALLING OF HIGH-STRENGTH SILICA FUME CONCRETE IN FIRE , 1993 .

[7]  Phil Purnell,et al.  An application of a damage constitutive model to concrete at high temperature and prediction of spalling , 2005 .

[8]  P. Monteiro,et al.  A New Method for Studying Stress-Induced Microcracks in Concrete , 1998 .

[9]  P. Sullivan.  A probabilistic method of testing for the assessment of deterioration and explosive spalling of high strength concrete beams in flexure at high temperature , 2004 .

[10]  James R. Lawson,et al.  Effects of elevated temperature exposure on heating characteristics, spalling, and residual properties of high performance concrete , 2001 .

[11]  Salman Azhar,et al.  Comparison of the strength and durability performance of normal- and high-strength pozzolanic concretes at elevated temperatures , 2001 .

[12]  M. Anson,et al.  Fire Behavior of High-Performance Concrete Made with Silica Fume at Various Moisture Contents , 1999 .

[13]  J. W. Dougill,et al.  Modes of failure of concrete panels exposed to high temperatures , 1972 .

[14]  Salman Azhar,et al.  Performance of metakaolin concrete at elevated temperatures , 2003 .

[15]  U.-M. Jumppanen.  Effect of strength on fire behaviour of concrete , 1989 .

[16]  Ali Behnood,et al.  Effects of silica fume addition and water to cement ratio on the properties of high-strength concrete after exposure to high temperatures , 2008 .

[17]  S. Diamond,et al.  On the occurrence of hollow-shell hydration grains in hydrated cement paste , 2000 .

[18]  C. Tang,et al.  Numerical tests of thermal cracking induced by temperature gradient in cement-based composites under thermal loads , 2007 .

[19]  G. Khoury.  Effect of fire on concrete and concrete structures , 2000 .

[20]  T. Hansen,et al.  Cracks in Concrete Core Due to Fire or Thermal Heating Shock , 1994 .

[21]  C. Tang,et al.  Thermal induced stress and associated cracking in cement-based composite at elevated temperatures––Part I: Thermal cracking around single inclusion , 2004 .

[22]  Takeo Hirashima,et al.  MECHANICAL PROPERTIES OF HIGH STRENGTH CONCRETE AT HIGH TEMPERATURES , 1999 .

[23]  Faris Ali,et al.  Is high strength concrete more susceptible to explosive spalling than normal strength concrete in fire? , 2002 .

[24]  Nicholas J. Carino,et al.  NIST Special Publication 919 International Workshop on Fire Performance of High-Strength Concrete, NIST, Gaithersburg, MD, February 13-14, 1997 Proceedings , 1997 .

[25]  Raymond J. Connolly,et al.  The spalling of concrete in fires , 1995 .

[26]  Bernhard A. Schrefler,et al.  Modelling of hygro-thermal behaviour of concrete at high temperature with thermo-chemical and mechanical material degradation , 2003 .

[27]  Wen-Wu Yang,et al.  Explosive spalling and residual mechanical properties of fiber-toughened high-performance concrete subjected to high temperatures , 2006 .

[28]  Z. Bažant,et al.  The chunnel fire. I: Chemoplastic softening in rapidly heated concrete , 1999 .