Numerical modeling of the fracture process in reinforced concrete by means of the continuum strong discontinuity approach. Part I: formulation

D.L LINERO, J. OLIVER, A.E. HUESPE

INGENIERíA E INVESTIGACIóN

UNIV NAC COLOMBIA

Año: 2010 vol. 30 p. 5 - 15

0120-5609

Reinforced concrete structures generally refers to beams, columnsand walls which are constituted by complex lattices ofsteel bars embedded in a concrete matrix, exhibiting multiplecracks due to high external loads. This paper presents the formulationof a numerical model aimed at describing the fractureprocess in reinforced concrete, from the volumetric ratioof concrete and steel. Crack formation and propagation in acomposite material is described in the model by an enhancedstrain field, such as that established in the continuum strongdiscontinuity approach and mixture theory. The compositematerial is constituted by a concrete matrix and one or twosteel bar orthogonal packages. The steel and concrete are representedby a one-dimensional plasticity model and a scalardamage model having different tension and compressionstrength, respectively. The dowel action and the bond-slipeffects between the bars and the matrix are described withadditional models relating component material stress andstrain. It is concluded that the proposed model can easily beimplemented in the finite element method, due to severalconventional nonlinear numerical process characteristicswhich remain. The model would also allow the problem to beanalysed at macroscopic scale, thereby avoiding a finite elementmesh having to be constructed for each componentmaterial and its interaction effects and reducing computationalcosts.