Fracture of concrete structural members subjected to blast

If reinforced concrete structures are to be safe under extreme impulsive loadings such as explosions, a broad understanding of the fracture mechanics of concrete under such events is needed. Most buildings and infrastructures which are likely to be subjected to terrorist attacks are borne by a reinforced concrete (RC) structure. Up to some years ago, the traditional method used to study the ability of RC structures to withstand explosions consisted on a choice between handmade calculations, affordable but inaccurate and unreliable, and full scale experimental tests involving explosions, expensive and not available for many civil institutions. In this context, during the last years numerical simulations have arisen as the most effective method to analyze structures under such events. However, for accurate numerical simulations, reliable constitutive models are needed. Assuming that failure of concrete elements subjected to blast is primarily governed by the tensile behavior, a constitutive model has been built that accounts only for failure under tension while it behaves as elastic without failure under compression. Failure under tension is based on the Cohesive Crack Model. Moreover, the constitutive model has been used to simulate the experimental structural response of reinforced concrete slabs subjected to blast. The results of the numerical simulations with the aforementioned constitutive model show its ability of representing accurately the structural response of the RC elements under study. The simplicity of the model, which does not account for failure under compression, as already mentioned, confirms that the ability of reinforced concrete structures to withstand blast loads is primarily governed by tensile strength.

[1]  Z. Bažant,et al.  Fracture and Size Effect in Concrete and Other Quasibrittle Materials , 1997 .

[2]  Rena C. Yu,et al.  Fracture behaviour of high-strength concrete at a wide range of loading rates , 2009 .

[3]  Anders Ansell,et al.  Air-blast-loaded, high-strength concrete beams. Part I: Experimental investigation , 2010 .

[4]  J. G. Hetherington,et al.  Response to Blast Loading of Concrete Wall Panels with Openings , 1999 .

[5]  A. Hillerborg,et al.  Analysis of crack formation and crack growth in concrete by means of fracture mechanics and finite elements , 1976 .

[6]  Charis J. Gantes,et al.  Elastic–plastic response spectra for exponential blast loading , 2004 .

[7]  Julio Gálvez,et al.  Three‐dimensional simulation of concrete fracture using embedded crack elements without enforcing crack path continuity , 2007 .

[8]  K. Thoma,et al.  Spall experiments for the measurement of the tensile strength and fracture energy of concrete at high strain rates , 2006 .

[9]  Tat-Seng Lok,et al.  Analysis of RC structures subjected to air-blast loading accounting for strain rate effect of steel reinforcement , 2007 .

[10]  J. Oliver MODELLING STRONG DISCONTINUITIES IN SOLID MECHANICS VIA STRAIN SOFTENING CONSTITUTIVE EQUATIONS. PART 2: NUMERICAL SIMULATION , 1996 .

[11]  E. Lavernia,et al.  An experimental investigation , 1992, Metallurgical and Materials Transactions A.

[12]  G. Hofstetter,et al.  An embedded strong discontinuity model for cracking of plain concrete , 2006 .

[13]  A. Razaqpur,et al.  Blast loading response of reinforced concrete panels reinforced with externally bonded GFRP laminates , 2007 .

[14]  L. J. Sluys,et al.  On the use of embedded discontinuity elements with crack path continuity for mode-I and mixed-mode fracture , 2002 .

[15]  Bibiana Luccioni,et al.  Concrete pavement slab under blast loads , 2006 .

[16]  Julio Gálvez,et al.  An embedded crack model for finite element analysis of concrete fracture , 2007 .

[17]  Bre,et al.  TESTING AND ANALYSIS OF REINFORCED CONCRETE PANELS SUBJECT TO EXPLOSIVE AND STATIC LOADING. , 1997 .

[18]  N. Gebbeken,et al.  A new material model for concrete in high-dynamic hydrocode simulations , 2000 .

[19]  Donald O. Dusenberry,et al.  Handbook for Blast-Resistant Design of Buildings , 2010 .

[20]  Klaus Fischer,et al.  SDOF response model parameters from dynamic blast loading experiments , 2009 .

[21]  G. R. Johnson,et al.  A Computational Constitutive Model for Glass Subjected to Large Strains, High Strain Rates and High Pressures , 2011 .

[22]  Li-Yi Wei,et al.  Part I: fundamentals , 2007, SIGGRAPH Courses.

[23]  Milan Jirásek,et al.  Comparative study on finite elements with embedded discontinuities , 2000 .

[24]  I. G. Cullis,et al.  Assessment of blast loading effects – Types of explosion and loading effects , 2010 .

[25]  Nur Yazdani,et al.  Performance of AASHTO girder bridges under blast loading , 2006 .

[26]  Anders Ansell,et al.  Air-blast-loaded, high-strength concrete beams. Part II: Numerical non-linear analysis , 2010 .

[27]  J. Oliver MODELLING STRONG DISCONTINUITIES IN SOLID MECHANICS VIA STRAIN SOFTENING CONSTITUTIVE EQUATIONS. PART 1: FUNDAMENTALS , 1996 .

[28]  Gabi Ben-Dor,et al.  Full-scale field tests of concrete slabs subjected to blast loads , 2008 .

[29]  J. W. Tedesco,et al.  Effects of Strain Rate on Concrete Strength , 1995 .

[30]  G. Plauk Concrete structures under impact and impulsive loading , 1982 .

[31]  Gustavo Morales-Alonso,et al.  Blast Response Analysis of Reinforced Concrete Slabs: Experimental Procedure and Numerical Simulation , 2011 .

[32]  S. H. Perry,et al.  Compressive behaviour of concrete at high strain rates , 1991 .

[33]  L. Malvar,et al.  Dynamic Increase Factors for Concrete , 1998 .

[34]  L. Malvar,et al.  A PLASTICITY CONCRETE MATERIAL MODEL FOR DYNA3D , 1997 .

[35]  Hong Hao,et al.  Numerical prediction of concrete slab response to blast loading , 2008 .

[36]  Jaap Weerheijm,et al.  Tensile failure of concrete at high loading rates : New test data on strength and fracture energy from instrumented spalling tests , 2007 .

[37]  Ronaldo I. Borja,et al.  A finite element model for strain localization analysis of strongly discontinuous fields based on standard Galerkin approximation , 2000 .