Mixed-mode fracture in lightweight aggregate concrete by using a moving mesh approach within a multiscale framework

Abstract Lightweight aggregate concrete (LWAC) has gained popularity as an alternative to ordinary concrete for structural purposes, due to its higher strength-to-weight ratio. The present work aims to present novel numerical results of complete failure simulations performed on pre-cracked beams made of LWAC, subjected to a mixed-mode fracture test. To this end, an innovative simulation algorithm for crack propagation within a multiscale framework has been adopted, specifically conceived for predicting micro-cracking in quasi-brittle heterogeneous materials under general loading conditions; such a strategy allows to take into account both the continuous crack propagation along a non-prescribed path and the crack penetration through a material interface. Path tracking for continuous crack propagation has been performed by using an advanced geometry optimization method coupling a moving mesh approach and a gradient-free optimization solver, whereas crack penetration has been simulated by means of a simplified re-initiation criterion at the interface, involving a material characteristic length. Several numerical experiments have been carried out, in order to investigate the influence of the Young’s modulus of lightweight aggregates on the peak and post-peak behavior. These results have been validated by comparing them with those obtained from fully homogenized analyses based on the LEFM approach.

[1]  Hongzhi Cui,et al.  Effect of porous lightweight aggregate on strength of concrete , 2004 .

[2]  C. Boulay,et al.  Taking into account the inclusions' size in lightweight concrete compressive strength prediction , 2005 .

[3]  Milan Jirásek,et al.  Evaluation of directional mesh bias in concrete fracture simulations using continuum damage models , 2008 .

[4]  D. Leguillon,et al.  A revisited criterion for crack deflection at an interface in a brittle bimaterial , 2001 .

[5]  J. L. Clarke,et al.  Structural lightweight aggregate concrete , 1993 .

[6]  David Taylor,et al.  The Theory of Critical Distances , 2007 .

[7]  H. Dumontet,et al.  Influence of volume fraction and characteristics of lightweight aggregates on the mechanical properties of concrete , 2009 .

[8]  Domenico Bruno,et al.  A fracture-ALE formulation to predict dynamic debonding in FRP strengthened concrete beams , 2013 .

[9]  Y. Ke,et al.  Identification of microstructural characteristics in lightweight aggregate concretes by micromechanical modelling including the interfacial transition zone (ITZ) , 2010 .

[10]  Shondeep L. Sarkar,et al.  Interdependence of microstructure and strength of structural lightweight aggregate concrete , 1992 .

[11]  M. Hüsem.  The effects of bond strengths between lightweight and ordinary aggregate-mortar, aggregate-cement paste on the mechanical properties of concrete , 2003 .

[12]  Rintoul,et al.  Reconstruction of the Structure of Dispersions , 1997, Journal of colloid and interface science.

[13]  R. Luciano,et al.  Damage mechanics of cement concrete modeled as a four-phase composite , 2014 .

[14]  P. Wriggers,et al.  Mesoscale models for concrete: homogenisation and damage behaviour , 2006 .

[15]  F. Greco,et al.  Prediction of Microscopic Interface Crack Onset in Fiber-Reinforced Composites by Using a Multi-Scale Homogenization Procedure , 2014 .

[16]  Keun-Hyeok Yang,et al.  Direct tensile strength of lightweight concrete with different specimen depths and aggregate sizes , 2014 .

[17]  J. Alexandre Bogas,et al.  Compressive behavior and failure modes of structural lightweight aggregate concrete – Characterization and strength prediction , 2013 .

[18]  Kaushik Bhattacharya,et al.  Effective toughness of heterogeneous media , 2014 .

[19]  R. Luciano,et al.  Micromechanical analysis of interfacial debonding in unidirectional fiber-reinforced composites , 2006 .

[20]  Jaime Planas,et al.  Mixed Mode Fracture of Concrete under Proportional and Nonproportional Loading , 1998 .

[21]  M. Tabbara,et al.  RANDOM PARTICLE MODEL FOR FRACTURE OF AGGREGATE OR FIBER COMPOSITES , 1990 .

[22]  Z. M. Wang,et al.  Mesoscopic study of concrete I: generation of random aggregate structure and finite element mesh , 1999 .

[23]  Ferhun C. Caner,et al.  Microplane Model M7 for Plain Concrete. II: Calibration and Verification , 2013 .

[24]  T. Belytschko,et al.  Analysis of three‐dimensional crack initiation and propagation using the extended finite element method , 2005 .

[25]  R. Singh,et al.  Study of localized damage in composite laminates using micro–macro approach , 2014 .

[26]  F. Greco,et al.  A two-scale failure analysis of composite materials in presence of fiber/matrix crack initiation and propagation , 2013 .

[27]  A. Huespe,et al.  From continuum mechanics to fracture mechanics: the strong discontinuity approach , 2002 .

[28]  Y. Xing,et al.  Accuracy of multiscale asymptotic expansion method , 2014 .

[29]  Lorenzo Leonetti,et al.  Adaptive multiscale modeling of fiber-reinforced composite materials subjected to transverse microcracking , 2014 .

[30]  A. Carpinteri,et al.  Snap-back Analysis of Fracture Evolution in Multi-Cracked Solids Using Boundary Element Method , 1999 .

[31]  Ran Huang,et al.  Approximate Strength of Lightweight Aggregate Using Micromechanics Method , 1998 .

[32]  Mehmet Gesoǧlu,et al.  Self-consolidating characteristics of concrete composites including rounded fine and coarse fly ash lightweight aggregates , 2014 .

[33]  Y. Ke,et al.  Micro-stress analysis and identification of lightweight aggregate’s failure strength by micromechanical modeling , 2014 .

[34]  Shuguang Li,et al.  General unit cells for micromechanical analyses of unidirectional composites , 2001 .

[35]  F. Greco,et al.  Non-linear macroscopic response of fiber-reinforced composite materials due to initiation and propagation of interface cracks , 2012 .

[36]  Shazim Ali Memon,et al.  Effect of lightweight aggregates on the mechanical properties and brittleness of lightweight aggregate concrete , 2012 .

[37]  A. Gerritse.  Design considerations for reinforced lightweight concrete , 1981 .

[38]  Ran Huang,et al.  EFFECT OF AGGREGATE PROPERTIES ON THE STRENGTH AND STIFFNESS OF LIGHTWEIGHT CONCRETE , 2003 .

[39]  Ted Belytschko,et al.  Coarse‐graining of multiscale crack propagation , 2010 .

[40]  E Weinan,et al.  Heterogeneous multiscale methods: A review , 2007 .

[41]  M. Elices,et al.  The cohesive zone model: advantages, limitations and challenges , 2002 .

[42]  Ercan Gürses,et al.  A computational framework of three-dimensional configurational-force-driven brittle crack propagation , 2009 .