Study of mechanisms of explosive spalling in high-strength concrete at high temperatures using acoustic emission

Abstract Mechanisms behind explosive spalling of high-strength concrete during a heating test were investigated on the basis of acoustic emission (AE) measurements of wet and air-dried specimens. The relation between the measured values of the internal temperature and vapour pressure and AE events produced by micro-cracking were investigated. It was found that AE events were indeed indicative of the state of the explosive failure process. Furthermore, b-value analysis was successfully applied to clarify the fracture process, regardless of the moisture content of the specimens.

[1]  Franz-Josef Ulm,et al.  THE "CHUNNEL" FIRE. II: ANALYSIS OF CONCRETE DAMAGE , 1999 .

[2]  W. Jason Weiss,et al.  Using acoustic emission to quantify damage in restrained fiber-reinforced cement mortars , 2003 .

[3]  G. A. Khoury,et al.  Polypropylene fibres in heated concrete. Part 2. Pressure relief mechanisms and modelling criteria , 2008 .

[4]  S. Puzzi,et al.  From criticality to final collapse: Evolution of the ''b-value" from 1.5 to 1.0 , 2009 .

[5]  Leena Sarvaranta,et al.  Microstructure of fibre mortar composites under fire impact-effect of polypropylene and polyacrylonitrile fibres , 1994 .

[6]  Masayasu Ohtsu,et al.  The history and development of acoustic emission in concrete engineering , 1996 .

[7]  M. V. M. S. Rao,et al.  Analysis of b-value and improved b-value of acoustic emissions accompanying rock fracture , 2005 .

[8]  J.G.M. van Mier,et al.  How to study drying shrinkage microcracking in cement-based materials using optical and scanning electron microscopy? , 2002 .

[9]  B. Meng,et al.  Influence of Polypropylene Fibres on the Thermal Strain of High Strength Concrete at High Temperatures , 2011 .

[10]  G. A. Khoury,et al.  Polypropylene fibres in heated concrete. Part 1: Molecular structure and materials behaviour , 2008 .

[11]  Luc Taerwe,et al.  On the Mechanism of Polypropylene Fibres in Preventing Fire Spalling in Self-Compacting and High-performance Cement Paste , 2008 .

[12]  Martine Wevers,et al.  Active and passive monitoring of the early hydration process in concrete using linear and nonlinear acoustics , 2009 .

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

[14]  A. Carpinteri,et al.  Fractal analysis of damage detected in concrete structural elements under loading , 2009 .

[15]  Takashi Horiguchi,et al.  Pore pressure development in hybrid fibre – reinforced high strength concrete at elevated temperatures , 2011 .

[16]  Zdenek P. Bazant,et al.  Analysis of Pore Pressure, Thermal Stress and Fracture in Rapidly Heated Concrete , 1997 .

[17]  Takashi Horiguchi,et al.  Effect of short fibers on residual permeability and mechanical properties of hybrid fibre reinforced high strength concrete after heat exposition , 2006 .

[18]  Cheon-Goo Han,et al.  Performance of spalling resistance of high performance concrete with polypropylene fiber contents and lateral confinement , 2005 .

[19]  Roman Lackner,et al.  How do polypropylene fibers improve the spalling behavior of in-situ concrete? , 2006 .

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

[21]  B. Gutenberg,et al.  Frequency of Earthquakes in California , 1944, Nature.

[22]  Long T. Phan,et al.  Pore pressure and explosive spalling in concrete , 2008 .

[23]  Pierre Kalifa,et al.  High-temperature behaviour of HPC with polypropylene fibres: From spalling to microstructure , 2001 .

[24]  Christian U. Grosse,et al.  Stress Drop and Stress Redistribution in Concrete Quantified Over Time by the b-value Analysis , 2006 .

[25]  Michael Forde,et al.  Assessing Damage of Reinforced Concrete Beam using b -value Analysis of Acoustic Emission Signals , 2003 .

[26]  A. Pollock.  Acoustic emission - 2: Acoustic emission amplitudes , 1973 .

[27]  Giuseppe Lacidogna,et al.  Critical Behaviour in Concrete Structures and Damage Localization by Acoustic Emission , 2006 .

[28]  Pietro Lura,et al.  Early-age acoustic emission measurements in hydrating cement paste: Evidence for cavitation during solidification due to self-desiccation , 2009 .

[29]  Giuseppe Lacidogna,et al.  Morphological Fractal Dimension Versus Power-law Exponent in the Scaling of Damaged Media , 2009 .

[30]  Surendra P. Shah,et al.  Application of Acoustic Emission and Laser Holography to Study Microfracture in Concrete , 1989, SP-112: Nondestructive Testing of Concrete.

[31]  S. Puzzi,et al.  Critical defect size distributions in concrete structures detected by the acoustic emission technique , 2008 .

[32]  Venkatesh Kodur,et al.  Optimization of the type and amount of polypropylene fibres for preventing the spalling of lightweight concrete subjected to hydrocarbon fire , 2004 .

[33]  Jean-Christophe Mindeguia,et al.  Temperature, Pore Pressure and Mass Variation of Concrete Subjected to High Temperature -- Experimental and Numerical Discussion on Spalling Risk , 2010 .