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Pages
- Title
- Embrittlement susceptibility of corroded pre-stressing steel in concrete during cathodic polarization.
- Creator
- Poeydomenge, Arnaud., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
Experiments and analyses were performed to better define the limits of concern regarding hydrogen embrittlement in association with application of cathodic protection to prestressed concrete. To accomplish this, prestressed concrete specimens were locally corroded to different levels by anodic polarization and then polarized to -1.30 V SCE. A procedure of examination was developed using strain gauges to determine the level of prestrain. Relatively few brittle failures of wires resulted due,...
Show moreExperiments and analyses were performed to better define the limits of concern regarding hydrogen embrittlement in association with application of cathodic protection to prestressed concrete. To accomplish this, prestressed concrete specimens were locally corroded to different levels by anodic polarization and then polarized to -1.30 V SCE. A procedure of examination was developed using strain gauges to determine the level of prestrain. Relatively few brittle failures of wires resulted due, at least in part, to a relatively low prestrain of the pretensioned tendons. A model was developed which, coupled with data from parallel research, permitted definition of the minimum cross section for brittle failure as a function of the magnitude of prestrain and corrosion morphology of the wire. These results were tabulated in a format that can be used during field inspection to identify structural elements for which fracture could occur upon application of cathodic protection.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/15417
- Subject Headings
- Prestressed concrete--Corrosion, Cathodic protection, Prestressed concrete--Embrittlement, Prestressed steel construction
- 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.
Show less - 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)
- Title
- Experimental Evaluation of the Structural Integrity of the Repairs for Corrosion-Damaged Marine Piles.
- Creator
- Bolivar, Juan Carlos, Reddy, Dronnadula V., Florida Atlantic University
- Abstract/Description
-
Corrosion damage is the mam cause of deterioration for reinforced concrete marine structures. Given the current economic downturn, it has become increasingly important to repair existing structures with techniques that prolong their life-cycle. The process to identify suitable repairs is affected by the lack of a consistent methodology to predict the outcome of the repairs. This investigation intends to compare the performance of seven different repairs, in terms of corrosion resistance,...
Show moreCorrosion damage is the mam cause of deterioration for reinforced concrete marine structures. Given the current economic downturn, it has become increasingly important to repair existing structures with techniques that prolong their life-cycle. The process to identify suitable repairs is affected by the lack of a consistent methodology to predict the outcome of the repairs. This investigation intends to compare the performance of seven different repairs, in terms of corrosion resistance, structural integrity, and cost-effectiveness. Following initial exposure to corrosion, the specimens were repaired using the proposed techniques. They were then tested for durability under simulated tidal conditions with periodic corrosion monitoring. The structural integrity was evaluated by crack scoring and ultimate load testing, and a comprehensive evaluation matrix was prepared, to determine which repairs were most adequate for corrosion damage. The results of this investigation substantiate that the repairs including carbon wrapping, HDPE jacketing, and MMFX steel, outperformed the rest of the repairs.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00012506
- Subject Headings
- Reinforced concrete--Corrosion, Underwater concrete construction--Maintenance and repair, Materials--Deterioration--Prevention, Fibrous composites--Evaluation
- Format
- Document (PDF)
- Title
- Strength and Durability of Rice Husk Ash-Modified Concrete in the Marine Environment.
- Creator
- Alvarez, Marcelina, Reddy, Dronnadula V., Florida Atlantic University
- Abstract/Description
-
The purpose of this research project is to compare the strength and durability characteristics of rice husk ash-modified concrete with those of normal concrete in the marine environment. Specimens prepared from concrete mixes with watercementitious ratios of 0.40 and 0.55, and rice husk ash content of 0%, 10%, and 20% were tested. The rice husk ash used was obtained from Agrilectric, power plant located in Lake Charles, Louisiana. The grinding of the ash to particle size of 7-J..tm to 45-J....
Show moreThe purpose of this research project is to compare the strength and durability characteristics of rice husk ash-modified concrete with those of normal concrete in the marine environment. Specimens prepared from concrete mixes with watercementitious ratios of 0.40 and 0.55, and rice husk ash content of 0%, 10%, and 20% were tested. The rice husk ash used was obtained from Agrilectric, power plant located in Lake Charles, Louisiana. The grinding of the ash to particle size of 7-J..tm to 45-J..tm was done by Process Research ORTECH Inc., Ontario, Canada. Strength and durability tests were performed, following ASTM (American Society for Testing and Materials) Standards. The significant fmdings are that the properties and quality of the rice husk ash-modified concrete are as good, if not better than normal concrete.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fau/fd/FA00012502
- Subject Headings
- Seawater corrosion, Reinforced concrete--Environmental testing, Concrete--Additives, Rice hulls--Testing, Limekilns--Testing
- Format
- Document (PDF)
- Title
- A STUDY OF THE EFFECT OF FLOW PARAMETERS ON THE CATHODIC PROTECTION OF A STEEL PLATE IN NATURAL SEAWATER.
- Creator
- MCCABE, KEVIN MICHAEL., Florida Atlantic University, Smith, Samuel W., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
The influence of hydrodynamic parameters and cathodic polarization on the formation of calcareous deposits on a steel plate in flowing seawater is investigated. Current density variations on the plate are determined for a combination of applied potentials and seawater velocities. Equations are developed to relate the cathodic current density distribution to variations in hydrodynamic and diffusional boundary layer thickness along the plate for laminar and turbulent flow regimes. A comparison...
Show moreThe influence of hydrodynamic parameters and cathodic polarization on the formation of calcareous deposits on a steel plate in flowing seawater is investigated. Current density variations on the plate are determined for a combination of applied potentials and seawater velocities. Equations are developed to relate the cathodic current density distribution to variations in hydrodynamic and diffusional boundary layer thickness along the plate for laminar and turbulent flow regimes. A comparison of experimental current densities on a bare plate to that predicted by theory is examined. Effects of flow on the formation and properties of calcareous deposits are discussed in light of recent developments in marine cathodic protection.
Show less - Date Issued
- 1984
- PURL
- http://purl.flvc.org/fcla/dt/14192
- Subject Headings
- Plates, Iron and steel--Cathodic protection, Carbon steel--Corrosion, Plates, Iron and steel--Fluid dynamics, Cathodic protection
- Format
- Document (PDF)
