The investigation of corrosion effects on the tensile behavior of reinforced concrete (RC) members is very important in region prone to high corrosion conditions. In this article, an experimental study concerning corrosion effects on tensile behavior of RC members is presented. For this purpose, a comprehensive experimental program including 58 cylindrical reinforced concrete specimens under various levels of corrosion is conducted. Some of the specimens (44) are located in large tub containing water and salt (5% salt solution); an electrical supplier has been utilized for the accelerated corrosion program. Afterwards, the tensile behavior of the specimens was studied by means of the direct tension tests. For each specimen, the tension stiffening curve is plotted, and their behavior at various load levels is investigated. Average crack spacing, loss of cross-section area due to corrosion, the concrete contribution to the tensile response for different strain levels, and maximum bond stress developed at each corrosion level are studied, and their appropriate relationships are proposed. The main parameters considered in this investigation are: degree concrete cover (c), ratio of of clear corrosion concrete (C w), cover reinforcement to diameter (d), reinforcement ratio (ρ), rebar diameter (c/d), and ratio of rebar diameter clear to reinforcement percentage (d / ρ).

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Harsh environmental conditions along with aggressive chemical agents are known as one of the main reasons behind damages observed in reinforced concrete members. Corrosion of reinforcement worldwide is one of the leading causes of damages occurred in reinforced concrete over the lifespan. There are many critical energy and transportation infrastructures located on coastal regions exposed to high humidity and chloride content where they are highly prone to reinforcement corrosion. This calls for retrofit methods, which safeguard not only the strength but also the durability of corrosion deteriorated reinforced concrete structures. Carbon fiber polymers considering their mechanical and chemical properties are recognized as one of the main retrofit techniques. In this study, the influence of different levels of corrosion on the structural behavior of reinforced concrete beams is studied. ABAQUS software package is employed to simulate the nonlinear behavior of reinforced concrete beams with tensile reinforcements and stir-ups corrosion degrees of 20% and 40%. The structural behavior of original damaged specimen as well as the same specimen strengthen with carbon fiber reinforced polymer (CFRP) is studied. The purpose of the retrofit is compensate for the loss of shear and flexural capacity of the member due to corrosion. Different variants for the arrangement of CFRP strips are studied and compared. The result of the current research further uncaps the efficiency of fiber polymers to secure strength and durability of corrosion damaged reinforced concrete members.

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Advanced performance-based earthquake engineering (PBEE), as documented by FEMA P-58 provisions, can well serve as the bedrock for a building-specific risk assessment framework. The methodology embraces three main sequential steps: collapse assessment, irreparability assessment, and component-wise loss estimation. The consequence of collapse or irreparability is typically assumed to be the total replacement value of the building. The irreparability model adopted by FEMA P-58 uses the residual drift of the building as the sole predictor. This article proposes a new irreparability prediction model tailored for the PBEE that is distinct because of two main features: (1) the monetary loss as a performance metric is chosen to inform the irreparability, enabling incorporation with the influence of different contributing factors, and (2) irreparability assessment is decoupled from the main body of the loss assessment and included as the post-loss analysis decision-making. Eventually, the proposed irreparability model called “post-loss analysis irreparability model (PLAIM)” is demonstrated through an illustrative example of a four-story wood light-frame building.

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