Nonlinear Analysis of RC Structures Using Isotropic Damage Model

Abstract

This article proposes a simple isotropic damage model within damage mechanics framework to represent the behavior of concrete in tension. Macroscopic evolution of tensile crack is considered as damage and is mathematically defined using an exponential function of tensile strain. A damage evolution law is formulated by applying strain equivalence principle to hyperbolic tension-softening curve. Value of damage variable is assumed theoretically to vary between '0' and '1' to denote uncracked and ruptured states, respectively. A smeared rotating crack model is coupled with damage formulation to simulate crack propagation effects in nonlinear finite element analysis of reinforced concrete (RC) structures. Many deficiencies of smeared crack model such as stress locking, mesh-induced directional bias, and instability in response computation for near-ultimate load are overcome using the coupled model. To verify the proposed model, nonlinear static response behavior of a RC beam is computed and compared with experimental and analytical results reported in literature. Effectiveness and applicability of the model to analyze practical structures are proved by analyzing a RC chimney. Nonlinear response of RC chimney is reviewed at global level while damage states of finite elements are studied at local level.

Effect of random structural damage on vehicle–track–bridge coupled response

“…Research on structural damage or damage mechanics has attracted wide attention in the field of civil engineering during past decades (Gonza´lez-Nicieza et al, 2008;Gopinath et al, 2012;Kaewunruen and Remennikov, 2009;Massart et al, 2007;Rehman et al, 2016;Sirca and Adeli, 2012;Tang et al, 2012). Different from traditional engineering structures, railway bridges and tracks generally bear the moving train loads characterized with high frequency and heavy weight.…”

An isotropic damage model to simulate collapse in reinforced concrete elements

“…There are many local damage models based on the damage framework such as: isotropic damage models (Kachanov 1958, Krajcinovic 1984, Lemaitre 1986, Simo and Ju 1987a, Lubliner et al 1989, Mazars and Pijaudier-Cabot 1989, Lubarda et al 1994, Faria et al 1998 1998, Comi 2001, Jason et al 2006, Contrafatto and Cuomo 2006, Wu et al 2006and Gopinath et al 2012; anisotropic damage models (Dragon and Mroz 1979, Cordebois and Sidoroff 1979, Krajcinovic and Fonseka 1981, Ortiz 1985, Simo and Ju 1987a, b, Ju 1989, 1990, Voyiadjis and AbuLebdeh 1994, Govindjee et al 1995, Halm and Dragon 1996, Fichant et al 1999, Lemaitre et al 2000, Carol et al 2001and Cicekli et al 2007. It is well kwon that local continuum damage models lead to a physically unrealistic description of the strain localization phenomenon.…”