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Influence Of Coating Defects Within The Lock Seams On The Corrosion Performance Of Aluminized Steel Drainage Pipes, Mohammed Al Yaarubi

USF Tampa Graduate Theses and Dissertations

The electrochemical behavior of aluminized steel is investigated to determine the corrosion performance of coating deficiencies generated within the lock seams during the fabrication of aluminized steel corrugated pipe. Electrochemical techniques and visual and profilometric analysis are used to assess the ability of the aluminum and zinc coating to provide sufficient galvanic protection to the underlying steel in the presence of a crevice. Also, Crevice coupons and lock-seam samples were used in this investigation in different environmental conditions simulating natural water conditions to relate the corrosion rate with the level of protection that the coating will provide. In addition, a …

Effects Of Physical And Chemical Characteristics Of Slags And Cements On Durability Of Portland Cement-Slag Blended Systems, Farzaneh Nosouhian

USF Tampa Graduate Theses and Dissertations

Ground granulated blast furnace slag (GGBFS) which is a commonly used supplementary cementitious material (SCM) needs to be more investigated for improving durability of concrete elements and service life of concrete structures. This research focuses on the effect of the physical and chemical characteristics of GGBFS and portland cement on durability of portland cement-slag blended systems. The effect of cement replacement level is also investigated using control mixes (no slag) and four different levels of slag content. To this end, eight GGBFS and eight portland cements were selected based on their physical characteristics and chemical composition. Four series of experimental …

Pursuing Resilience Of Coastal Communities Through Sustainable And Integrated Urban Water Management, Pacia Díaz

USF Tampa Graduate Theses and Dissertations

Reliability of water supply in the urban setting has become essential for communities to function and thrive. It is needed for more than mere human consumption and well-being. Although modern cities have water treatment and distribution systems, pressures from urbanization, population growth and the anticipated pressures of climate change are affecting the quality of water supply and the reliability of treatment and distribution systems. There is therefore an urgent need to take appropriate measures to improve the resilience of water supply systems before the impacts are irreversible.

Improving the resilience of water supply systems can be a challenge. In the …

Corrosion Of Steel In Submerged Concrete Structures, Michael Thomas Walsh

USF Tampa Graduate Theses and Dissertations

This investigation determined that severe corrosion of steel can occur in the submerged portions of reinforced concrete structures in marine environments. Field studies of decommissioned pilings from actual bridges revealed multiple instances of strong corrosion localization, showing appreciable local loss of steel cross-section. Quantitative understanding of the phenomenon and its causes was developed and articulated in the form of a predictive model. The predictive model output was consistent with both the corrosion rate estimates and the extent of corrosion localization observed in the field observations. The most likely explanation for the observed phenomena that emerged from the understanding and modeling …

Feasibility Of Application Of Cathodic Prevention To Cracked Reinforced Concrete In Marine Service, Kevin Williams

USF Tampa Graduate Theses and Dissertations

Corrosion can take place as chloride ions accumulate above a critical concentration (CT) at the surface of a reinforcing bar inside concrete in marine service. The initiation of corrosion can be delayed by polarizing the steel cathodically, which is known to increase the value of CT. That effect is the basis of the cathodic prevention (CPrev) method to control corrosion of reinforcing steel in concrete. However, concrete cracks are a common occurrence and at cracks, the buildup of chloride ions is accelerated to the extent that CPrev may be less effective. The findings from an ongoing investigation to determine the …