Service Life of Reinforced Concrete Structures with Corrosion Damage due to Chloride Attack

It is well known that the chloride in concrete can results in rebar corrosion. Due to the expansive nature of rust, rebar corrosion deteriorates the reinforced concrete structures by creating damages in the concrete around the rebar such as cracking and spalling, which affect the durability and service of life of reinforced concrete structures. This study presents a comprehensive model for predicting service life of reinforced concrete structures exposed to chloride attack. The model characterizes various stages in the process of corrosion damage: the initiation of corrosion, the initiation of cracks and critical size of cracks. The initiation process is modeled by coupled chloride and moisture diffusion equations. The initiation of cracks and critical crack length are determined by coupling the corrosion rate, the permeation of corrosion product and mechanical restraint of surrounding concrete. Until the initiation of cracks, the mechanical problem is solved by using elastic theory for thick wall cylinder. After the cracking, the theory of thick wall cylinder is combined with nonlinear fracture mechanics. The period of each deterioration stage can be determined using the present model.

[1]  Zdeněk P. Bažant,et al.  Creep and Shrinkage of Concrete , 1965, Nature.

[2]  Yunping Xi,et al.  Chloride Penetration in Nonsaturated Concrete , 2003 .

[3]  Z. P. Bažant,et al.  Nonlinear water diffusion in nonsaturated concrete , 1972 .

[4]  Z. Bažant,et al.  Moisture diffusion in cementitious materials Adsorption isotherms , 1994 .

[5]  Martys,et al.  Universal scaling of fluid permeability for sphere packings. , 1994, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[6]  Yunping Xi,et al.  Microstructurally based mechanisms for modeling shrinkage of cement paste at multiple levels , 1993 .

[7]  Stavroula J. Pantazopoulou,et al.  Modeling Cover-Cracking due to Reinforcement Corrosion in RC Structures , 2001 .

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

[9]  C. Andrade,et al.  Chloride threshold values to depassivate reinforcing bars embedded in a standardized OPC mortar , 2000 .

[10]  Yunping Xi,et al.  Shrinkage of cement paste and concrete modelled by a multiscale effective homogeneous theory , 1997 .

[11]  Lars-Olof Nilsson,et al.  Chloride binding capacity and binding isotherms of OPC pastes and mortars , 1993 .

[12]  Yunping Xi,et al.  Moisture diffusion in cementitious materials Moisture capacity and diffusivity , 1994 .

[13]  Yunping Xi,et al.  An experimental study on the effect of chloride penetration on moisture diffusion in concrete , 2002 .

[14]  Z. Bažant,et al.  Modeling Chloride Penetration in Saturated Concrete , 1999 .

[15]  E. Garboczi,et al.  Simulation Studies of the Effects of Mineral Admixtures on the Cement Paste-Aggregate Interfacial Zone (SP-105) , 1991 .

[16]  D. Coronelli,et al.  CORROSION CRACKING AND BOND STRENGTH MODELING FOR CORRODED BARS IN REINFORCED CONCRETE , 2002 .

[17]  Dan M. Frangopol,et al.  MULTISCALE MODELING OF INTERACTIVE DIFFUSION PROCESSES IN CONCRETE , 2000 .

[18]  Roland W. Lewis,et al.  A fully nonlinear analysis of heat and mass transfer problems in porous bodies , 1980 .