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Full-Text Articles in Engineering
Rfid Tags For Detecting Concrete Degradation In Bridge Decks, Tyler J. Lesthaeghe, Samuel Frishman, Stephen D. Holland, Terry J. Wipf
Rfid Tags For Detecting Concrete Degradation In Bridge Decks, Tyler J. Lesthaeghe, Samuel Frishman, Stephen D. Holland, Terry J. Wipf
Tyler J Lesthaeghe
Steel reinforcing bar (rebar) corrosion due to chlorine ingress is the primary degradation mechanism for bridge decks. In areas where rock salt is used as a de-icing agent, salt water seeps into the concrete through cracks, causing corrosion of the rebar and potentially leading to catastrophic failure if not repaired. This project explores the use of radio frequency identification (RFID) tags as low-cost corrosion sensors. RFID tags, when embedded in concrete, will fail due to corrosion in the same manner as rebar after prolonged exposure to salt water. In addition, the presence of salt water interferes with the ability to …
Comparing Electrochemical Impedance Spectroscopy Methods For Estimating The Degree Of Delamination Of Organic Coatings On Steel, S. A. Mccluney, S. N. Popova, Branko N. Popov, Ralph E. White, R. B. Griffin
Comparing Electrochemical Impedance Spectroscopy Methods For Estimating The Degree Of Delamination Of Organic Coatings On Steel, S. A. Mccluney, S. N. Popova, Branko N. Popov, Ralph E. White, R. B. Griffin
Ralph E. White
Electrochemical impedance spectroscopy (EIS) was used to evaluate the degree of delamination of the epoxy primer Uniprime ED-41 electrocoated on phosphate-treated cold-rolled steel in 3.5% NaCl exposed to air. Specimens with coating thicknesses of 20.3 and 20.8 µm and surface areas of 78.5 cm2 were used. Coating parameters were obtained using a circuit-analog model. The area of delamination was estimated using several EIS parameters, including the pore resistance and the break point frequency. These values were compared to the corroded area determined visually. All methods considered exhibited a strong correlation over some or all of the range of …
A Mathematical Model For The Initial Corrosion Rate Of A Porous Layer On A Rotating Disk Electrode, William E. Ryan, Ralph E. White, S. L. Kelly
A Mathematical Model For The Initial Corrosion Rate Of A Porous Layer On A Rotating Disk Electrode, William E. Ryan, Ralph E. White, S. L. Kelly
Ralph E. White
A mathematical model is presented for the initial corrosion rate of a porous layer on a rotating disk electrode. The model is used to predict the corrosion potential and corrosion current density for a porous electrode made of pure iron in aerated caustic solutions. The dependence of these predictions on some of the properties of the porous layer is presented. It is shown that the corrosion rate depends significantly on the specific surface area of the porous electrode.
Development Of A New Electrodeposition Process For Plating Of Zn-Ni-X (X = Cd, P) Alloys: I. Corrosion Characteristics Of Zn-Ni-Cd Ternary Alloys, Anand Durairajan, Bala S. Haran, Ralph E. White, Branko N. Popov
Development Of A New Electrodeposition Process For Plating Of Zn-Ni-X (X = Cd, P) Alloys: I. Corrosion Characteristics Of Zn-Ni-Cd Ternary Alloys, Anand Durairajan, Bala S. Haran, Ralph E. White, Branko N. Popov
Ralph E. White
A new Zn-Ni-Cd plating process was developed which offers a unique way of controlling and optimizing the Ni and Cd contents in the final deposit. Zinc-nickel-cadmium alloy was deposited from a 0.5 M NiSO4 + 0.2 M ZnSO4 bath in the presence of 0.015 M CdSO4 and 1 g/L nonyl phenyl polyethylene oxide. Using this process a Zn-Ni-Cd ternary alloy, with a higher nickel content as compared to that obtained from conventional Zn-Ni baths, was synthesized. The Zn-Ni-Cd alloy coatings deposited from an electrolyte containing 0.015 M (0.3%) CdSO4 has a Zn to Ni ratio of …
A Review Of Survivability And Remedial Actions Of Tidal Current Turbines
A Review Of Survivability And Remedial Actions Of Tidal Current Turbines
Faculty of Engineering University of Malaya
Tidal current energy is one of the most predictable ocean renewable energies. Survivability of the device used to harness tidal power and its remedial actions are critical to ensure a successful power generation. Marine environment is harsh with the continuous attacks of waves, current saline water and microorganism. Support structures are discussed including gravity base, monopile, tripod/piled jacket and floating structure. Extreme weather increases the wave height and current speed to produce high loading at the turbine. Support structure is designed to sustain the loadings from the extreme weather. Protective seabed unit should be included to prevent the seabed scouring. …
Engineering And Sustainability Performance Of Self-Compacting Palm Oil Mill Incinerated Waste Concrete
Faculty of Engineering University of Malaya
The different stages in the processing of palm oil generate various types of waste by-products, which have to be disposed of appropriately for a cleaner environment and to reduce pollution. In this study, palm oil clinker (POC), one of the by-products of the palm oil mill, was utilized in the production of self-compacting concrete (SCC). SCC has diverse types of structural application due to its own enhanced self-consolidating behaviour. The proportioning of the mixes was based on particle packing, which integrates both aggregate packing and void volume for a mix of aggregates. Combinations of POC and natural aggregate were studied …