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One of the most crucial factors affecting the service life of reinforced concrete (RC) structures attacked by aggressive ions is reinforcement corrosion. As the steel corrosion progresses, crack propagation in concrete medium endangers the serviceability and the strength of RC structural members. In this study, a nonlinear mathematical model for determining the displacement and stress fields in...

L. SMITH Controlling corrosion in production tubing is essential for maintaining production and for preventing loss of well control. Materials for use downhole have to meet criteria for corrosion resistance and also mechanical requirements. The potential corrosion rate can be estimated and the risks of sulphide stress corrosion cracking assessed on the basis of the anticipated environmental con...

The damage and fracture of materials are technologically of enormous interest due to their economic and human cost. They cover a wide range of phenomena like e.g. cracking of glass, aging of concrete, the failure of fiber networks in the formation of paper and the breaking of a metal bar subject to an external load. Failure of composite systems is of utmost importance in naval, aeronautics and ...

Concrete is usually highly alkaline (pH around 12), thus protecting reinforcement against corrosion. The occurrence of oxides is favored when the medium pH surrounding the bar is in values near to 9 or lower. Aggressive substances for reinforcements generally enter concrete through its pore structure, and cracks tend to decrease pH, stimulating corrosion process. There are several causes for cr...

In this paper, an experimental study is presented on the influence of PET warping on shear performance, such as diagonal shear cracking load, peak load, and energy dissipation of RC columns with stirrup corrosion before strengthening. The experimental program involved an electrochemical process to accelerate the migration of chlorides from an external electrolyte into the tested columns, a wett...

Acoustic emission (AE) techniques have been extensively studied and applied to nondestructive testings (NDT) of concrete and concrete structures. For damage evaluation, AE behavior of concrete under compression could be analyzed, applying the rate process theory. Based on Loland's model in damage mechanics, a relation between AE rate and the damage parameter is correlated. By quantifying intact...

Corrosion, stress-corrosion cracking or corrosion-initiated fatigue significantly impact maintenance downtime and structural life limitations of aging aircraft. Both legacy and new air platforms such as the Joint Strike Fighter (JSF), realize that corrosion will likely continue to be a structural challenge that warrants a structural health management system to provide accurate, cost effective a...