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Considerable numbers of reinforced concrete (RC) bridges in the US are structurally deficient mainly due to corrosion. Corrosion affects the structural integrity by deteriorating the material properties and the bond at the steel–concrete interface. Currently, the available bond strength models considering corrosion deterioration are either complex or developed based on the limited database. This paper proposes a simple probabilistic model of bond strength considering corrosion using multivariable regression based on a comprehensive database collected from the literature. The predictions are found to be accurate and unbiased when compared with the experimental results. Then, the proposed bond model is employed in the nonlinear finite element models of intact and corroded RC beams to investigate the importance of steel–concrete bond modeling on evaluating flexural behavior of the beams. Lastly, the minimum required development length for a given corrosion level is calculated and its sufficiency is investigated through a numerical analysis. [ABSTRACT FROM AUTHOR]

Abstract: A bibliometric analysis based on Science Citation Index (SCI) published by Institute of Scientific Information (ISI) was carried out to identify the global research related to lead in drinking water field from 1991 to 2007 and to improve the understanding of research trends in the same period. The results from this analysis indicate that there have been an increasing number of annual publications mainly during two periods: from 1992 to 1997 and from 2004 to 2007. United States produced 37% of all pertinent articles followed by India with 8.0% and Canada with 4.8%. Science of the Total Environment published the most articles followed by Journal American Water Works Association and Toxicology. Summary of the most frequently used keywords are also provided. “Cadmium” was the most popular author keyword in the 17years. Furthermore based on bibliometric results four research aspects were summarized in this paper and the historical research review was also presented. [Copyright &y& Elsevier]

As both reliability analyses and systematic inspection programs for the world’s infrastructure gain increased usage and prominence, it becomes more important to use the information from routine visual inspections to update lifetime reliability assessments and resulting life-cycle inspection/repair strategies. The Army Corps of Engineers currently uses reliability analyses to economically justify the major rehabilitation of navigation structures. This paper illustrates how the Condition Index visual inspections for locks and dams can be modified and used to update the reliability analysis of a steel miter gate. The miter gates on two existing locks and dams along the Mississippi River are used as examples for corrosion and fatigue deterioration. The approach used is applicable to any structure where the inspection condition states are quantitative and a model exists to relate visual inspection results to the actual deterioration state of the structure. [Copyright &y& Elsevier]

• Testing of residual web bearing strength of corroded steel beams. • Numerical modeling of web buckling behaviors of corroded steel girders. • Developing quantitative relationship between corrosion condition and web bearing strength. • Proposing steel girder web bearing strength reduction factor in bridge loading rating. Aging bridges have become an important issue in the United States. One of the most dominant forms of deterioration for steel bridges is corrosion, which is typically due to moisture exposure and water leakage through deck joints. In cold regions, frequent use of deicing chemicals during the winter season further contributes to the corrosion process. Over the years, corrosion can become serious enough to disconnect the girder's web from its flanges. This excessive rust accumulation and metal area loss pose significant concerns for the reduction of the structural capacity of a girder, especially at its ends. In this paper, new corroded sample preparation and testing procedures were developed and implemented to study the residual web bearing capacity of corroded steel beam specimens in the lab. The laboratory testing results were used to extend the study to evaluate the residual web bearing capacity of corroded steel bridge girders. Corroded steel beam specimens were approximated in two forms in laboratory testing. In the first form, web thinning was achieved by prolonged submersion in bleach solution, to develop surface corrosion and section loss. In the second form, web holes were cut out of specimens with a plasma torch. Loading tests were performed on scaled steel beam specimens to investigate the consequent reduction in web bearing capacity due to web thinning and web area losses. The reaction at girder ends was simulated by a compression force exerted on the top flange of the steel beam specimens through a loading plate of the Material Testing System. The residual strengths of the steel beam specimens, varying in levels of corrosion, were analyzed and compared with the 3-D finite element modeling results. A quantitative relationship between corrosion condition and residual web bearing strength of I-plate steel girders is developed based on the laboratory testing and numerical modeling results. The findings in this study align with the observations from the real-world bridge practice. The proposed table of web bearing strength reduction factors can be used as a reference for evaluating residual web bearing capacity of corroded steel girders in bridge loading rating. [ABSTRACT FROM AUTHOR]