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Title: Effects of cement alkalinity, exposure conditions and steel-concrete interface on the time-to-corrosion and chloride threshold for reinforcing steel in concrete.
Creator: Nam, Jingak., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Effects of (1) cement alkalinity (low, normal and high), (2) exposure conditions (RH and temperature), (3) rebar surface condition (as-received versus cleaned) and (4) density and distribution of air voids at the steel-concrete interface on the chloride threshold and time-to-corrosion for reinforcing steel in concrete have been studied. Also, experiments were performed to evaluate effects of RH and temperature on the diffusion of chloride in concrete and develop a method for ex-situ pH...
Show moreEffects of (1) cement alkalinity (low, normal and high), (2) exposure conditions (RH and temperature), (3) rebar surface condition (as-received versus cleaned) and (4) density and distribution of air voids at the steel-concrete interface on the chloride threshold and time-to-corrosion for reinforcing steel in concrete have been studied. Also, experiments were performed to evaluate effects of RH and temperature on the diffusion of chloride in concrete and develop a method for ex-situ pH measurement of concrete pore water. Once specimens were fabricated and exposed to a corrosive chloride solution, various experimental techniques were employed to determine time-to-corrosion, chloride threshold, diffusion coefficient and void density along the rebar trace as well as pore water pH. Based upon the resultant data, several findings related to the above parameters have been obtained as summarized below. First, time for the corrosion initiation was longest for G109 concrete specimens with high alkalinity cement (HA). Also, chloride threshold increased with increasing time-to-corrosion and cement alkalinity. Consequently, the HA specimens exhibited the highest chloride threshold compared to low and normal alkalinity ones. Second, high temperature and temperature variations reduced time-to-corrosion of reinforcing steel in concrete since chloride diffusion was accelerated at higher temperature and possibly by temperature variations. The lowest chloride threshold values were found for outdoor exposed specimens suggesting that variation of RH or temperature (or both) facilitated rapid chloride diffusion. Third, an elevated time-to-corrosion and chloride threshold values were found for the wire brushed steel specimens compared to as-received ones. The higher ratio of [OH-]/[Fe n+] on the wire brushed steel surface compared to that of as-received case can be the possible cause because the higher ratio of this parameter enables the formation of a more protective passive film on the rebar. Fourth, voids at the steel-concrete interface facilitated passive film breakdown and onset of localized corrosion. This tendency for corrosion initiation increased in proportion to void size irrespective of specimen type. Also, [Cl -]th decreased with increasing void diameter. In addition, new ex-situ leaching method for determining concrete pore water alkalinity was developed.
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Date Issued: 2004
PURL: http://purl.flvc.org/fcla/dt/12096
Subject Headings: Reinforced concrete construction, Chlorides, Steel--Corrosion, Composite reinforced concrete
Format: Document (PDF)

Title: Atmospheric Corrosion Study of Weathering Steel Using Sensor Technology.
Creator: Hereng, Yann, Granata, Richard D., Florida Atlantic University
Abstract/Description: This research tests the corrosion resistance of weathering steel against carbon steel exposed to dry and humid cycles during laboratory experiments. Various environments are tested and include the following parameters: chloride concentration, pH and wetting time. Corrosion values from weight loss analysis are given and studied for the same environments. X-ray diffraction characterized the formation of different oxides as a function of the environment and gave a better understanding on the...
Show moreThis research tests the corrosion resistance of weathering steel against carbon steel exposed to dry and humid cycles during laboratory experiments. Various environments are tested and include the following parameters: chloride concentration, pH and wetting time. Corrosion values from weight loss analysis are given and studied for the same environments. X-ray diffraction characterized the formation of different oxides as a function of the environment and gave a better understanding on the formation of the protective patina on the weathering steel, and validated that chamber experiments reproduce field conditions. The study is supported by the design, test and validation of an easily deployable galvanic atmospheric corrosion sensor that allowed the monitoring of the corrosion rate on an hourly basis.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012526
Subject Headings: Steel, Structural--Corrosion, Reinforced concrete construction
Format: Document (PDF)

Title: Analysis of blast/explosion resistant reinforced concrete solid slab and T-Beam bridges.
Creator: Abdelahad, Firas A., Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: This study presents and illustrates a methodology to calculate the capacity of an existing reinforced concrete bridge under a non-conventional blast load due to low and intermediate pressures. ATBlast program is used to calculate the blast loads for known values of charge weight and stand off distance. An excel spreadsheet is generated to calculate ultimate resistance, equivalent elastic stiffness, equivalent elastic deflection, natural period of the beam, the maximum deflection, and the...
Show moreThis study presents and illustrates a methodology to calculate the capacity of an existing reinforced concrete bridge under a non-conventional blast load due to low and intermediate pressures. ATBlast program is used to calculate the blast loads for known values of charge weight and stand off distance. An excel spreadsheet is generated to calculate ultimate resistance, equivalent elastic stiffness, equivalent elastic deflection, natural period of the beam, the maximum deflection, and the maximum rotation in the support for a simple span solid slab and T-Beam bridges. The allowable rotation could be taken as to two degrees. Naval Facility Engineering Command (NAVFAC) approach was adopted, where the inputs were material properties, span length, and area of reinforcement. The use of the Fiber Reinforced Polymer for increasing the capacity of an existing bridge is also presented in this study. Parametric studies were carried out to evaluate the performance of the solid slab and T-Beam bridges under the assumed blast load.
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Date Issued: 2008
PURL: http://purl.flvc.org/fcla/flaent/EN00154040/68_1/98p0132d.pdf, http://purl.flvc.org/FAU/58001
Subject Headings: Concrete beams, Vibration, Bridges, Concrete, Fatigue, Reinforced concrete construction, Bridges, Concrete, Design and construction
Format: Document (PDF)

Title: Strength and durability of fly ash-based fiber-reinforced geopolymer concrete in a simulated marine environment.
Creator: Martinez Rivera, Francisco Javier, Sobhan, Khaled, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: This research is aimed at investigating the corrosion durability of polyolefin fiber-reinforced fly ash-based geopolymer structural concrete (hereafter referred to as GPC, in contradistinction to unreinforced geopolymer concrete referred to as simply geopolymer concrete), where cement is completely replaced by fly ash, that is activated by alkalis, sodium hydroxide and sodium silicate. The durability in a marine environment is tested through an electrochemical method for accelerated corrosion...
Show moreThis research is aimed at investigating the corrosion durability of polyolefin fiber-reinforced fly ash-based geopolymer structural concrete (hereafter referred to as GPC, in contradistinction to unreinforced geopolymer concrete referred to as simply geopolymer concrete), where cement is completely replaced by fly ash, that is activated by alkalis, sodium hydroxide and sodium silicate. The durability in a marine environment is tested through an electrochemical method for accelerated corrosion. The GPC achieved compressive strengths in excess of 6,000 psi. Fiber reinforced beams contained polyolefin fibers in the amounts of 0.1%, 0.3%, and 0.5% by volume. After being subjected to corrosion damage, the GPC beams were analyzed through a method of crack scoring, steel mass loss, and residual flexural strength testing. Fiber reinforced GPC beams showed greater resistance to corrosion damage with higher residual flexural strength. This makes GPC an attractive material for use in submerged marine structures.
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Date Issued: 2013
PURL: http://purl.flvc.org/fau/fd/FA0004037
Subject Headings: Concrete mixing -- Quality control, Green chemistry, Polymer composites, Reinforced concrete -- Corrosion -- Testing, Reinforced concrete construction
Format: Document (PDF)

Title: CRACKING OF CONCRETE DUE TO CORROSION OF VARIOUS EMBEDDED METALS.
Creator: TURNER, DEAN HUDSON., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The objective of this investigati.on was to contribute to the determination of a suitable metallic coating for steel reinforcement in concrete exposed to a marine environment and possibly to stray current. Concrete specimens embedded with steel, aluminum, cadmium, copper, molybdenum, nickel, and galvanized steel were exposed to sea water. Direct current was impressed on these to accelerate corrosion of the reinforcement so that cracking of the concrete could be observed within the time limit...
Show moreThe objective of this investigati.on was to contribute to the determination of a suitable metallic coating for steel reinforcement in concrete exposed to a marine environment and possibly to stray current. Concrete specimens embedded with steel, aluminum, cadmium, copper, molybdenum, nickel, and galvanized steel were exposed to sea water. Direct current was impressed on these to accelerate corrosion of the reinforcement so that cracking of the concrete could be observed within the time limit of the investigation. Aluminum, cadmium, copper, and nickel were found to have no beneficial effect on concrete cracking as compared to steel. In addition, no correlation between oxide-metal volume ratio and concrete time-to-cracking could be observed. It was found that corrosion of molybdenum has little or no tendency to crack concrete and its corrosion potential and active behavior approximates that of steel, indicating it may be an excellent coating.
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Date Issued: 1976
PURL: http://purl.flvc.org/fcla/dt/13820
Subject Headings: Reinforced concrete--Cracking, Underwater concrete construction, Reinforced concrete--Corrosion
Format: Document (PDF)

Title: Experimental and Modeling Study of Chloride Ingress into Concrete and Reinforcement Corrosion Initiation.
Creator: Yu, Hui, Hartt, William H., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Effects of reinforcement and coarse aggregate on chloride ingression into concrete and reinforcement corrosion initiation have been studied with experimental and modeling (finite element method) analyses. Once specimens were fabricated and exposed to a chloride solution, various experimental techniques were employed to determine the effect of reinforcement and coarse aggregate on time-to-corrosion and chloride ingress and concentration at corrosion locations. Model analyses were performed to...
Show moreEffects of reinforcement and coarse aggregate on chloride ingression into concrete and reinforcement corrosion initiation have been studied with experimental and modeling (finite element method) analyses. Once specimens were fabricated and exposed to a chloride solution, various experimental techniques were employed to determine the effect of reinforcement and coarse aggregate on time-to-corrosion and chloride ingress and concentration at corrosion locations. Model analyses were performed to verify and explain the experimental results. Based upon the results, it was determined that unexpectedly higher chloride concentrations were present on the top of the rebar trace than that to the side at the same depth and an inverse concentration gradient (increasing [Cl-] with increasing depth) occurred near the top of rebars. Also, coarse aggregate volume profile in close proximity to the rebar and spatial distribution of these aggregates, in conjunction with the physical obstruction afforded by reinforcement to chloride flow, complicates concrete sampling for Cl- intended to define the critical concentration of this species to initiate corrosion. Modeling analyses that considered cover thickness, chloride threshold concentration, reinforcement size and shape, and coarse aggregate type and percolation confirmed the experimental findings. The results, at least in part, account for the relatively wide spread in chloride corrosion threshold values reported in the literature and illustrate that more consistent chloride threshold concentrations can be acquired from mortar or paste specimens than from concrete ones.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012582
Subject Headings: Reinforced concrete construction--Corrosion, Chlorides--Diffusion rate, Composite reinforced concrete, Concrete--Chemical resistance
Format: Document (PDF)

Title: Comparative evaluation of the performance of concrete wall panels, with and without fiber reinforcement.
Creator: Germain, Gerson S., Florida Atlantic University, Reddy, Dronnadula V.
Abstract/Description: This investigation addresses the evaluation of the increase in structural integrity of concrete wall panels by the addition of polypropylene fibers. The test methodology used was the evaluation of flexural (simply-supported and cantilever), shear (in-plane and punching), and impact behavior. The concrete panels comprised sets with (i) regular reinforcement (ACI code based), (ii) Reinforced concrete panels: 0.2% fibers with minimum ACI reinforcement, FRC 2, (iii) 0.3% fibers without...
Show moreThis investigation addresses the evaluation of the increase in structural integrity of concrete wall panels by the addition of polypropylene fibers. The test methodology used was the evaluation of flexural (simply-supported and cantilever), shear (in-plane and punching), and impact behavior. The concrete panels comprised sets with (i) regular reinforcement (ACI code based), (ii) Reinforced concrete panels: 0.2% fibers with minimum ACI reinforcement, FRC 2, (iii) 0.3% fibers without reinforcement, FRC 3, and (iv) plain beams without reinforcement. The instrumentation consisted of deflection and electrical strain gages, a slope indicator for slope testing, and an oscilloscope with a camera attachment for monitoring load and energy traces in impact testing. The normalized (adjusted for concrete strength variations) ultimate load and energy values were compared. The findings indicated enhancement of ductility and shear strength for the fiber reinforced specimens, which are very desirable for sudden and impact loading conditions associated with hurricane-type loading.
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Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/12678
Subject Headings: Concrete walls--Design and construction, Reinforced concrete, Fiber
Format: Document (PDF)

Title: Influence of pozzolanic admixtures on concrete pore water pH, chloride diffusion and chloride binding.
Creator: Charvin, Stephanie., Florida Atlantic University, Hartt, William H.
Abstract/Description: This report describes the results obtained from reinforced concrete slabs having different fly ash and silica fume content. The specimens are submitted to periodic seawater ponding. PH measurements as well as free and total chloride analyses were achieved at 1213 days in order to study the alkalinity, resistance to chloride ingress and binding properties afforded by each mix design. Water absorption experiments were also conducted at different relative humidities and in water. Pore water pH...
Show moreThis report describes the results obtained from reinforced concrete slabs having different fly ash and silica fume content. The specimens are submitted to periodic seawater ponding. PH measurements as well as free and total chloride analyses were achieved at 1213 days in order to study the alkalinity, resistance to chloride ingress and binding properties afforded by each mix design. Water absorption experiments were also conducted at different relative humidities and in water. Pore water pH was found to decrease with increasing admixture content and increasing relative humidity. The permeability to chloride ions was significantly reduced in the fly ash blends whereas most of the silica fume blends exhibited effective diffusion coefficients and chloride concentrations at the depth of steel marginally better than the controls. Both the fly ash and silica fume blends showed similar binding capacity at a given replacement ratio, the percentage of bound chloride increasing with increasing admixture content.
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Date Issued: 1999
PURL: http://purl.flvc.org/fcla/dt/15664
Subject Headings: Reinforced concrete construction--Corrosion, Concrete--Additives
Format: Document (PDF)

Title: Concrete diffusivity and its correlation with chloride deposition rate on concrete exposed to marine environments.
Creator: Echevarria, Victor Anthony., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The aim of this study was to investigate the diffusion of chloride ions into concrete samples that were exposed in scenarios that simulate the splash, tidal, atmospheric, and immersed portions of a marine structure. To study the atmospheric deposition, the project also investigated the relationship between chloride ion deposition on the wet candle and its accumulation into concrete samples. Results from the wet candle experiment indicated that between 2% and 45% of the chlorides deposited per...
Show moreThe aim of this study was to investigate the diffusion of chloride ions into concrete samples that were exposed in scenarios that simulate the splash, tidal, atmospheric, and immersed portions of a marine structure. To study the atmospheric deposition, the project also investigated the relationship between chloride ion deposition on the wet candle and its accumulation into concrete samples. Results from the wet candle experiment indicated that between 2% and 45% of the chlorides deposited per square meter of exposed area could be found within the concrete samples. After 6 months, slag G1a blocks showed the most resistance to chloride penetration in the tidal and splash simulations. After 10 months of exposure, fly ash samples had the slowest rates of diffusion in the tidal simulation while the fly ash + silica fume samples and the slag samples measured similar rates of diffusion within the tidal zone. After 90 days of curing, cylinders composed of 20% fly ash & 8% silica fume measured the highest average resistivity values and were found to be less vulnerable to chloride ion penetration than the 20% fly ash and the 50% slag concrete through rapid migration tests.
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Date Issued: 2012
PURL: http://purl.flvc.org/FAU/3358557
Subject Headings: Reinforced concrete, Construction, Corrosion, Composite reinforced concrete, Corrosion, Testing, Concrete, Fluid dynamics, Concrete, Chemical resistance, Chlorides, Diffusion rate
Format: Document (PDF)

Title: Flexural Behavior of Concrete Using Basalt FRP Rebar.
Creator: Trotsek, Dylan, Arockiasamy, Madasamy, Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: The objective of this research is to determine if the deflection equations currently adopted in ACI 440.1r-15 and previously ACI 440.1r-06 accurately reflect the flexural behavior of an overreinforced Basalt Fiber Reinforced Polymer (BFRP) concrete beam. This was accomplished with experimental, analytical and numerical models. The experiment consisted of two beams doublyreinforced with BFRP rebar. A three-point flexural test on beams with a 30 in. clear span was performed and the deflections...
Show moreThe objective of this research is to determine if the deflection equations currently adopted in ACI 440.1r-15 and previously ACI 440.1r-06 accurately reflect the flexural behavior of an overreinforced Basalt Fiber Reinforced Polymer (BFRP) concrete beam. This was accomplished with experimental, analytical and numerical models. The experiment consisted of two beams doublyreinforced with BFRP rebar. A three-point flexural test on beams with a 30 in. clear span was performed and the deflections were recorded with a dial gauge and LVDT system. This data was compared to the equations from ACI 440.1r-06, ACI 440.1r-15, Branson’s equation and a numerical model created in ANSYS Mechanical APDL. Experimental results show a stiffer beam than expected when compared to the four predictive models for deflection. This can be due to the level of over-reinforcement and the small clear-span to depth ratio. Further research should be conducted to determine the cause for the additional stiffness.
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Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00004920, http://purl.flvc.org/fau/fd/FA00004920
Subject Headings: Reinforced concrete construction--Mathematical models., Structural analysis (Engineering), Fiber-reinforced concrete.
Format: Document (PDF)

Title: Feasibility studies on carbon fiber composite cables in reinforced/prestressed concrete structures.
Creator: Kanneganti, Srikanth., Florida Atlantic University, Arockiasamy, Madasamy, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The feasibility studies on the use of non-metallic continuous fiber reinforcement in reinforced and prestressed concrete structures are presented herein. Experimental results from studies on relaxation, bond and transfer length of Carbon Fiber Composite Cables (CFCC) are presented followed by results of flexural load tests on concrete beams reinforced and prestressed with CFCC. Durability of the CFCC is another prime concern, and hence part of the study also focuses on establishing the...
Show moreThe feasibility studies on the use of non-metallic continuous fiber reinforcement in reinforced and prestressed concrete structures are presented herein. Experimental results from studies on relaxation, bond and transfer length of Carbon Fiber Composite Cables (CFCC) are presented followed by results of flexural load tests on concrete beams reinforced and prestressed with CFCC. Durability of the CFCC is another prime concern, and hence part of the study also focuses on establishing the durability of the CFCC exposed to aggressive environments like alkali solution and sea water. The basic mechanics that govern the structural behavior of the beams, provide important insight into the potential that CFCC has to offer.
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Date Issued: 1994
PURL: http://purl.flvc.org/fcla/dt/15080
Subject Headings: Fiber reinforced plastics, Reinforced concrete, Fiber, Composite materials, Prestressed concrete construction--Deterioration, Carbon fibers
Format: Document (PDF)

Title: Obstruction of chloride diffusion in concrete by embedded reinforcing bars.
Creator: Cros, Pascal., Florida Atlantic University, Hartt, William H.
Abstract/Description: A study was performed of the effect of reinforcing bars on chloride diffusion into concrete. These bars act as obstacles to chloride movement, and this obstruction allows the chloride concentration to build-up faster along the top of the reinforcing bar than elsewhere. As a consequence, the critical chloride threshold to initiate corrosion of the steel is reached sooner than otherwise expected. This research was performed using two different methods. First, chloride analyses were performed on...
Show moreA study was performed of the effect of reinforcing bars on chloride diffusion into concrete. These bars act as obstacles to chloride movement, and this obstruction allows the chloride concentration to build-up faster along the top of the reinforcing bar than elsewhere. As a consequence, the critical chloride threshold to initiate corrosion of the steel is reached sooner than otherwise expected. This research was performed using two different methods. First, chloride analyses were performed on chloride exposed concrete blocks by taking cores in the concrete and drillings along the trace of the top bars. Second, concrete blocks models were analyzed by finite element analysis and the effect of the obstruction by the bar quantified. The role of the reinforcing bar in the chloride diffusional flow is discussed considering these two methods.
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Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/13239
Subject Headings: Reinforcing bars--Corrosion, Reinforced concrete construction--Corrosion, Concrete--Additives, Chlorides--Diffusion rate
Format: Document (PDF)

Title: Feasibility of using carbon fiber reinforced plastic tendons in prestressed concrete Double-Tee bridge system.
Creator: Zhuang, Ming., Florida Atlantic University, Arockiasamy, Madasamy, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: One of the major problems the construction industry faces today is corrosion of reinforcing and prestressing steel, which significantly affects the durability of concrete structures. Fiber reinforced plastics (FRPs) are highly regarded as prospective replacement for steel in prestressed concrete structures under corrosive environment. This investigation was conducted to establish the feasibility of using Carbon Fiber Composite (CFC) cables as reinforcing/prestressing elements in concrete...
Show moreOne of the major problems the construction industry faces today is corrosion of reinforcing and prestressing steel, which significantly affects the durability of concrete structures. Fiber reinforced plastics (FRPs) are highly regarded as prospective replacement for steel in prestressed concrete structures under corrosive environment. This investigation was conducted to establish the feasibility of using Carbon Fiber Composite (CFC) cables as reinforcing/prestressing elements in concrete bridge structures. Besides investigating durability of CFC cables and pretensioned concrete beams with CFC cables in adverse environments (alkali and seawater), flexure and shear tests were performed on single Double-Tee beams, together with service load behavior, fatigue strength and ultimate load capacity tests on a half scale model Double-Tee girder bridge system prestressed with CFC cables. Exposure to seawater and alkali environments has no adverse effect on the strength of the CFRP tendons as well as the pretensioned beams with CFRP. Based on the flexural strength tests on Double-Tee beams, the bond between CFRP tendons and concrete is satisfactory. The Double-Tee bridge system exhibited good fatigue resistance and adequate ductility under ultimate load conditions. The ultimate load capacity of the bridge is approximately three times the service load corresponding to two HS20-44 trucks and equals 2.4 times the first crack load. Finite element analyses were carried out to predict elastic deformations and collapse load of the Double-Tee bridge prestressed with CFC cables. Feasibility of using CFC cables in bridge structures is assessed based on the experimental and analytical parameters such as deflections, strains, crack distributions and crack widths.
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Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/12465
Subject Headings: Carbon fibers, Composite construction, Fiber reinforced plastics, Bridges, Iron and steel, Reinforced concrete construction, Prestressed concrete construction
Format: Document (PDF)

Title: Bulk diffusion of high performance concrete specimens exposed to different levels of sodium chloride and seawater.
Creator: Arias, Wendy J., Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The purpose of this study was to investigate the performance to chloride penetration of specimens made with three base compositions (three different supplementary cementitious materials) and water to cementitious ratios of 0.35, 0.41, or 0.47. The specimens were subjected to bulk diffusion test or full immersion. The mixes were exposed to 0.1 M, 0.6 M, or 2.8 M sodium chloride solution for different periods of time. Also, partially immersed specimens were exposed to indoor and outdoor...
Show moreThe purpose of this study was to investigate the performance to chloride penetration of specimens made with three base compositions (three different supplementary cementitious materials) and water to cementitious ratios of 0.35, 0.41, or 0.47. The specimens were subjected to bulk diffusion test or full immersion. The mixes were exposed to 0.1 M, 0.6 M, or 2.8 M sodium chloride solution for different periods of time. Also, partially immersed specimens were exposed to indoor and outdoor exposures (tidal, splash, barge). Chloride concentration profiles were obtained and the apparent diffusion coefficient was calculated. The skin effect was found only on some chloride profiles exposed to 0.1 M sodium chloride solution. The chloride binding capacity was calculated; specimens with 20% Fly Ash and 8% Silica Fume had the highest binding capacity (70.99%). The apparent diffusivity coefficient was found to be dependent on the curing regime as well as the water to cement ratio. The correlation between effective resistivity and apparent diffusion coefficient was determined.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004076, http://purl.flvc.org/fau/fd/FA00004076
Subject Headings: Bulk solids flow, Concrete -- Corrosion, Concrete, Effect of salt on, Reinforced concrete -- Deterioration, Sustainable construction
Format: Document (PDF)

Title: Centrally prestressed fiber reinforced concrete columns.
Creator: Grijalba, Daniel A., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: With the need to improve corrosion resistance in columns and piles, the innovative idea of Centrally Prestressed Fiber Reinforced Concrete (CPFRC) columns is a promising solution. The first step is to compare if the compressive strength of any mix is affected by the size, geometry, or even the inclusion of polyolefin fibers in a specimen. The results showed that the cylinder size of 4 in. x 8 in., which is the most common size used by the testing labs, has the highest compressive strength....
Show moreWith the need to improve corrosion resistance in columns and piles, the innovative idea of Centrally Prestressed Fiber Reinforced Concrete (CPFRC) columns is a promising solution. The first step is to compare if the compressive strength of any mix is affected by the size, geometry, or even the inclusion of polyolefin fibers in a specimen. The results showed that the cylinder size of 4 in. x 8 in., which is the most common size used by the testing labs, has the highest compressive strength. There was no sign on compressive strength improvement with the use of polyolefin fibers, except for reduction in cracking size and concrete spalling. The second step compared the ultimate strength, ductility characteristics and failure mode of CPFRC columns to conventional columns. CPFRC showed adequate axial and flexural resistance, in addition to ductile behavior similar to regular reinforced concrete columns.
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Date Issued: 2011
PURL: http://purl.flvc.org/FAU/3332253
Subject Headings: Prestressed concrete construction, Strength of materials, Composite reinforced concrete, Concrete, Chemical resistance
Format: Document (PDF)

Title: Chloride penetration into concrete structures exposed to the marine atmosphere.
Creator: Shill, Scott Thompson, Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Chloride ions present in the marine atmosphere contained in marine aerosols is investigated for a relationship with chloride that accumulated into concrete. Chloride profiles are conducted on several concrete mixes containing fly ash, silica fume, and slag, with water to cementitious ratios of 0.35, 0.41, and 0.47. The chloride accumulation in concrete samples exposed to the environment is investigated with relation to the chloride deposition from the marine atmosphere measured via the wet...
Show moreChloride ions present in the marine atmosphere contained in marine aerosols is investigated for a relationship with chloride that accumulated into concrete. Chloride profiles are conducted on several concrete mixes containing fly ash, silica fume, and slag, with water to cementitious ratios of 0.35, 0.41, and 0.47. The chloride accumulation in concrete samples exposed to the environment is investigated with relation to the chloride deposition from the marine atmosphere measured via the wet candle test. Results indicate a possible relationship for the total accumulated chloride in the concrete with the accumulated chloride deposition (wet candle). Over the exposure periods, concrete specimens with 50% slag addition and 0.47 w/cm had the lowest average rates of chloride accumulation for deposition under 100 g/m2day. Chloride accumulation was lower in concrete containing 20% fly ash and 8% silica fume with 0.35 w/cm for chloride deposition rates over 200 g/m2day.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004227, http://purl.flvc.org/fau/fd/FA00004227
Subject Headings: Chlorides -- Diffusion rate, Chlorides -- Environmental aspects, Concrete -- Chemical resistance, Concrete -- Permeability, Reinforced concrete -- Construction -- Corrosion
Format: Document (PDF)

Title: Corrosion initiation and propagation on corrosion resistant alloys embedded in concrete by accelerated chloride transport.
Creator: Gutierrez Tellez, Francisco., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Two duplex stainless steels rebars: UNS32304SS and UNS32101SS, were selected to investigate the corrosion initiation and propagation in reinforced concrete specimens. The investigation is divided in two phases with two different methods to accelerate the transport of chlorides through the concrete and initiate corrosion in a short period of time. After corrosion had initiated and propagated for some time; selected specimens were terminated for visual examination. On specimens selected for...
Show moreTwo duplex stainless steels rebars: UNS32304SS and UNS32101SS, were selected to investigate the corrosion initiation and propagation in reinforced concrete specimens. The investigation is divided in two phases with two different methods to accelerate the transport of chlorides through the concrete and initiate corrosion in a short period of time. After corrosion had initiated and propagated for some time; selected specimens were terminated for visual examination. On specimens selected for autopsy, the rebars in the top row showed corrosion to various degrees. Corrosion had propagated to such extent on the terminated specimens that the specimen showed cracks. Stray current might have caused accelerated corrosion on rebars where corrosion had initiated. Based on chloride concentrations measured at the rebar trace, corrosion initiated: on S32101 rebars on average at 7.9 kg/m3, and S32101 rebars on average at 6.0 kg/m3. The findings suggest that S32304 rebars corroded at a slower than S32101.
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Date Issued: 2013
PURL: http://purl.flvc.org/fcla/dt/3362380
Subject Headings: Concrete, Corrosion, Concrete construction, Reinforced concrete, Chemical resistance, Steel, Structural, Corrosion
Format: Document (PDF)

Title: Initiation and propagation of corrosion in dry-cast reinforced concrete ring specimens.
Creator: Seo, Bongjoon, Presuel-Moreno, Francisco, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The corrosion propagation stage of D-CRP (types F and C) was tested under immersion in water, high humidity, and covered with wet sand. The half-cell potential, linear polarization test, and electrochemical impedance spectroscopy measurements were performed. Selected specimens were terminated after 300 days of exposure and visually inspected. Based on corrosion potential measurements obtained during the corrosion propagation observation, and calculated corrosion rate based on LPR measurements...
Show moreThe corrosion propagation stage of D-CRP (types F and C) was tested under immersion in water, high humidity, and covered with wet sand. The half-cell potential, linear polarization test, and electrochemical impedance spectroscopy measurements were performed. Selected specimens were terminated after 300 days of exposure and visually inspected. Based on corrosion potential measurements obtained during the corrosion propagation observation, and calculated corrosion rate based on LPR measurements: all specimens were actively corroding. Additionally, EIS-Rc values were calculated for FS, CS and CH specimens. The Rc_EIS were generally greater than Rc_LPR values. EIS spectra for CI and FI specimens usually included mass transport limitations, as these specimens were immersed. Both type of specimens immersed in water (FI and CI), appeared to have higher corrosion rate based on LPR-Rc. However, upon autopsy it was revealed that a more modest amount of corrosion occurred on the reinforcing steel of FI and CI terminated specimens.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004226, http://purl.flvc.org/fau/fd/FA00004226
Subject Headings: Concrete -- Deterioration, Concrete construction, Corrosion and anti corrosives, Reinforced concrete -- Chemical resistance, Tubular steel structures -- Deterioration
Format: Document (PDF)

Title: Durability testing of reinforced concrete beams under fatigue loading in a simulated marine environment.
Creator: Ahn, Woo-Suk., Florida Atlantic University, Reddy, Dronnadula V.
Abstract/Description: This thesis addresses the evaluation of the durability of reinforced concrete marine structures subjected to fatigue loading. The laboratory investigation was carried out on full and half size reinforced concrete specimens with three different water cement ratios (0.3, 0.4, and 0.56), static and fatigue loading conditions, and epoxy-coated and regular black steel reinforcements; a mineral admixture (silica fume), and a corrosion inhibitor (calcium nitrite) were used for specimens made with...
Show moreThis thesis addresses the evaluation of the durability of reinforced concrete marine structures subjected to fatigue loading. The laboratory investigation was carried out on full and half size reinforced concrete specimens with three different water cement ratios (0.3, 0.4, and 0.56), static and fatigue loading conditions, and epoxy-coated and regular black steel reinforcements; a mineral admixture (silica fume), and a corrosion inhibitor (calcium nitrite) were used for specimens made with water/cement ratio 0.4 concrete. The marine tidal zone was simulated by alternate filling and draining of the tank (wet and dry cycles), and a galvanostatic corrosion technique to accelerate corrosion of rebar was introduced. Half-cell potentials and changes of crack width were measured periodically during the exposure and followed by ultimate strength testing. The significant findings include adverse effect of fatigue loading, existence of an explicit size effect, poor performance of epoxy coated steel, and negative effect of the increasing water/cement ratio.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15178
Subject Headings: Concrete beams--Fatigue, Underwater concrete construction, Reinforced concrete--Fatigue, Seawater--Corrosion
Format: Document (PDF)

Title: Experimental evaluation of the durability of fly ash-based geopolymer concrete in the marine environment.
Creator: Edouard, Jean-Baptiste., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description: The construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in...
Show moreThe construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in the way of producing concrete. However, to seriously consider geopolymer binders as an alternative to ordinary Portland cement, the durability of this new material should be evaluated in any comparative analysis. The main purpose of this study was to evaluate the durability characteristics of low calcium fly ash-based geopolymer concretes subjected to the marine environment, compared to ordinary Portland cement concrete with similar exposure. To achieve this goal, 8 molar geopolymer, 14 molar geopolymer and ordinary Portland cement concrete mixes were prepared and tested for exposure in seawater. Compressive strengths in the range of 2900 to 8700 psi (20-60 MPa) were obtained. The corrosion resistance performance of steel-reinforced concrete beams, made of these mixes, was also studied, using an accelerated electrochemical method, with submergence in salt water. The test results indicated that the geopolymer concrete showed excellent resistance to chloride attack, with longer time to corrosion cracking, compared to ordinary Portland cement concrete.
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Date Issued: 2011
PURL: http://purl.flvc.org/FAU/3170960
Subject Headings: Reinforced concrete, Corrosion, Testing, Reinforced concrete construction, Concrete, Mixing, Quality control, Environmental chemistry, Industrial applications, Polymer composites
Format: Document (PDF)

Reinforced concrete construction (10)	+ -
Fiber reinforced plastics (5)	+ -
Composite reinforced concrete (4)	+ -
Concrete (4)	+ -
Prestressed concrete construction (4)	+ -

Chemical resistance (3)	+ -
Chlorides (3)	+ -
Corrosion (3)	+ -
Reinforced concrete (3)	+ -
Reinforced concrete construction--Corrosion (3)	+ -
Testing (3)	+ -
Carbon fibers (2)	+ -
Chlorides--Diffusion rate (2)	+ -
Concrete construction (2)	+ -
Concrete--Additives (2)	+ -
Corrosion and anti-corrosives (2)	+ -
Polymer composites (2)	+ -
Reinforced concrete, Fiber (2)	+ -
Reinforced concrete--Corrosion (2)	+ -
Steel, Structural (2)	+ -
Steel, Structural--Corrosion (2)	+ -
Underwater concrete construction (2)	+ -
ANSYS (Computer system) (1)	+ -
Alkali-aggregate reactions (1)	+ -
Bridges, Concrete (1)	+ -
Bridges, Iron and steel (1)	+ -
Bridges--Design and construction (1)	+ -
Bridges--Fatigue (1)	+ -
Bulk solids flow (1)	+ -
Carbon composites (1)	+ -

College of Engineering and Computer Science (24)	+ -
Florida Atlantic University (24)	+ -
Department of Ocean and Mechanical Engineering (17)	+ -
Department of Civil, Environmental and Geomatics Engineering (7)	+ -
Hartt, William H. (7)	+ -

Arockiasamy, Madasamy (6)	+ -
Presuel-Moreno, Francisco (4)	+ -
Reddy, Dronnadula V. (4)	+ -
Granata, Richard D. (2)	+ -
Abdelahad, Firas A. (1)	+ -
Ahn, Woo-Suk. (1)	+ -
Anesta, Heather R. (1)	+ -
Arias, Wendy J. (1)	+ -
Baker, William Arnold. (1)	+ -
Bolivar, Juan Carlos (1)	+ -
Charvin, Stephanie. (1)	+ -
Chen, Di (1)	+ -
Cros, Pascal. (1)	+ -
Echevarria, Victor Anthony. (1)	+ -
Edouard, Jean-Baptiste. (1)	+ -
Germain, Gerson S. (1)	+ -
Grijalba, Daniel A. (1)	+ -
Gutierrez Tellez, Francisco. (1)	+ -
Hereng, Yann (1)	+ -
Kanneganti, Srikanth. (1)	+ -
Martinez Rivera, Francisco Javier (1)	+ -
Merantus, Stanley W. (1)	+ -
Nam, Jingak. (1)	+ -
Qu, Rong. (1)	+ -
Sanchez, Erika Maria. (1)	+ -

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