Engineering Commons^™

Strengthening Of Corroded Steel Structures Using Cfrp – An Experimental Review, Ghada El-Mahdy Ph.D., P.Eng, Abdallah H. Yassin, Abdel El Rahman Khaled

Civil Engineering

Fibre reinforced polymers (FRP) have been widely used to strengthen reinforced concrete structures, however, nowadays their use to strengthen steel structures is under investigation. In particular, the need to strengthen corroded steel structures found in aggressive environments, such as marine environments, which have undergone a reduction in cross-sectional area and hence a reduction in their load-carrying capacity is in need of studying. The main problems that arise when using carbon fibre reinforced polymer (CFRP) sheets to strengthen steel structures is the weakness in the interfacial bond between the CFRP and the steel surface, the thinness of CFRP sheet, and the …

Retrofit Of Corroded Corrugated Metal Culverts Using Gfrp Slip-Liner, Rahulreddy Chennareddy

Civil Engineering ETDs

Culverts are water conveyance structures, typically used to allow water flow and maintain a balance between the flow streams without interrupting structures such as highways and bridges. Corrugated metal pipes (CMPs) have been used as culverts in North America since the 1950s because of their low cost and simple construction method. Today, the corrosion of CMPs is a major problem faced by all U.S. Departments of Transportation. There is an urgent need to provide an efficient solution, one that is corrosion-resistant, to retrofit thousands of corroded CMPs across the country. High specific strength, high strength to weight ratio, corrosion resistance, …

Application Of Bayesian Networks To Integrity Management Of Energy Pipelines, Wei Xiang

Electronic Thesis and Dissertation Repository

Metal-loss corrosion and third-party damage (TPD) are the leading threats to the integrity of buried oil and natural gas pipelines. This thesis employs Bayesian networks (BNs) and non-parametric Bayesian networks (NPBNs) to deal with four issues with regard to the reliability-based management program of corrosion and TPD. The first study integrates the quantification of measurement errors of the ILI tools, corrosion growth modeling and reliability analysis in a single dynamic Bayesian network (DBN) model, and employs the parameter learning technique to learn the parameters of the DBN model from the ILI-reported and filed-measured corrosion depths. The second study develops the …

Integrated Sensor Network For Monitoring Steel Corrosion In Concrete Structures, José Enrique Ramón-Zamora, José Manuel Gandia-Romero, Román Bataller, Ana Martínez-Ibernón, Isabel Gasch, Juan Soto

International Conference on Durability of Concrete Structures

The developed Integrated Sensor Network (ISN) allows a non-destructive monitoring of the rebar condition at different parts of the structure. The corrosion sensor allows the accurate determination of the corrosion rate (µm/year). Moreover, additional sensors are integrated in order to detect relevant changes in the concrete electrochemical condition.

The ISN has been published as an international invention patent (reference number WO 2016/177929 A1). The system is based on an economic, simple, reliable and durable technology, which makes its implementation viable on new and repaired reinforced concrete structures (RCS). Therefore, it is also possible monitoring non-accessible parts such as deep foundations …

Micro-Mechanical Analysis Of Corrosion Products Formed During Long-Term Carbonation Induced Corrosion Of Steel, Marijana Serdar, Dubravka Bjegovic, Valérie L’Hostis, Stéphane Poyet, Damien Féron

International Conference on Durability of Concrete Structures

During corrosion distinct types of corrosion products form, composed of different ratios of ferrous ions and oxide, hydroxides. Corrosion products have different physical and mechanical properties, mainly density, resistivity, volume and modulus of elasticity compared to iron. Knowing properties of corrosion products is indispensable for service life modelling of structures and can give valuable insight into the long-term corrosion propagation process. In this study micro-indentation method was used to evaluate mechanical properties of different layers formed during long-term carbonation induced corrosion of steel in concrete. Investigation was performed on three sets of reinforced concrete samples, that underwent corrosion during 50, …

Comparison Data Between Hybrid And Galvanic Anode Installation In The Arousa Island Bridge, José Antonio Becerra Mosquera, Diego Carro López, José Enrique Pardo Landrove, José Manuel Millán Pérez

International Conference on Durability of Concrete Structures

The Arousa Island Bridge, with its 1980 m is the only road access to the Arousa Island. Built in 1985, this single-cell box girder divided in 40 spans runs entirely on the sea. The deck is between 2 to 12 m above sea level, so after 25 years in a marine environment, the structure showed reinforcement corrosion, especially in piles and deck bottom. Attending to the corrosion damages, caused simply from a chloride attack, the local government decided to intervene with an ambitious repair project. This decision has been taken only after an exhaustive cost analysis to determine the feasibility …

Effect Of Time-Dependent Chloride Profile And Temperature Variation On Chloride Diffusion In Concrete, Feras Alsheet, A. Ghani Razaqpur

International Conference on Durability of Concrete Structures

Reinforcement corrosion due to chlorides diffusion is one of the main problems in reinforced concrete structures exposed to certain environments. The diffusion rate is function of chloride surface concentration, concrete temperature, humidity, composition and microstructure. The intruded chlorides are partially chemically bound by the concrete and it is the unbound or free chloride which upon exceeding a defined threshold initiates corrosion. The time to corrosion initiation depends on the above variables; therefore, it is important to model their spatial and temporal variations in a manner that will yield a realistic estimate of the actual initiation period. In this study, the …

Durability Design Of Segmental Linings For Intended Service Life Of Tunnels, Mehdi Bakhshi, Verya Nasri

International Conference on Durability of Concrete Structures

In one-pass lining systems, the durability of tunnel structure is directly related to durability of concrete segments acting as both the initial support and the tunnel final lining. In this paper, most-frequent degradation mechanisms of concrete linings are discussed including chloride- and carbonation- induced corrosions, sulfate, acid and freeze-and-thaw attacks, and alkali-aggregate reactions. Mitigation method for each specific degradation mechanism is explained. A durability factor specific to railway and subway tunnel known as stray current corrosion is presented. Mitigation methods for this specific corrosion together with coupling effects with other conventional damage mechanisms are explained. Prescriptive approaches for durability design …

Sustainable Concrete With Seawater And Corrosion Resistant Reinforcement: Results Of Monitoring Of Corrosion Behaviour, Elena Redaelli, Maddalena Carsana, Federica Lollini, Matteo Gastaldi, Forood Torabian Isfahani

International Conference on Durability of Concrete Structures

The use of seawater for mixing concrete for reinforced concrete structures is prohibited, since it can promote steel corrosion. However, the use of seawater would contribute to decrease the environmental impact of concrete, in particular in those regions of the world where potable water is a precious resource. The project SEACON-INFRAVATION between University of Miami and Politecnico di Milano, with various industrial partners, aims at investigating the use of seawater for the construction of sustainable and durable reinforced concrete structures and infrastructures. Within the project, that included a vast campaign of laboratory tests, also two demo projects – one in …

Climate Resilient Concrete Structures In Marine Environment Of Bangladesh, Sudarshan Srinivasan, Ian Gibb

International Conference on Durability of Concrete Structures

Bangladesh has a vast coastal infrastructure seriously affected by climate change and associated extreme environmental conditions. The rural construction sector in Bangladesh will be undergoing rapid growth in the next 10 years through rural infrastructure development programmes funded by the Asian Development Bank and the World Bank. The Local Government Engineering Department (LGED in Bangladesh), owns the rural concrete infrastructure, maintains around 380, 000 linear metres of concrete bridges or culverts in the rural coastal areas and are planning to build more than 200,000 linear metres during the next ten years. In order to design and construct durable concrete structures …

The Performance Of Concrete In A Marine Environment, Michael D. Thomas, Edward G. Moffatt

International Conference on Durability of Concrete Structures

This paper presents a summary of data from wide range of concretes following periods of marine exposure ranging up to 25 years. Data are presented from more than 100 different concrete mixtures. The various types of concrete include fibre-reinforced concrete (FRC), ultra-high performance concrete (UHPC), concrete with a range of supplementary cementing materials (SCM such as fly ash, slag, and silica fume) and replacement levels (e.g. up to 58% fly ash and 80% slag), lightweight-aggregate concrete (LWAC) and concrete containing alkali-silica reactive aggregate. Testing included measuring chloride concentration profiles, electrochemical corrosion measurements (for steel-reinforced concrete), and various electrical and mechanical …

Development Of Local And Global Corrosion Sensing Technique To Monitor Structural Behavior Of Prestressed Concrete Structures, Dewan Z. Hossain

FIU Electronic Theses and Dissertations

Corrosion of steel rebar in reinforced concrete structures is a concern for highway bridge owners. According to 2002 study by the Federal Highway Administration, ~15% of the highway bridges in the US are structurally deficient due to corrosion and have an estimated annual direct cost of $8.3 billion. Generally, in post-tensioned bridges, ducts filled with poor or incomplete grouting can allow the tendons to come into contact with water, leading to corrosion and fracture. Although new and improved procedures of grouting have been developed to reduce the instances of poor grouting, the problem of how to reliably inspect tendons on …

Corrosion Durability Of A Nano-Particle Enriched Zinc-Rich Coating System For Highway Steel Bridges, Saiada Fuadi Fancy

FIU Electronic Theses and Dissertations

Corrosion is a major concern for the long-term durability and structural integrity of steel components of highway bridges when unprotected. The application of protective coatings has been widely used for corrosion mitigation of atmospherically exposed structural steel. At present, the zinc-rich primer (ZRP) based three-coat system is widely used in the United States. The metallic zinc pigment ideally would provide corrosion resistance by sacrificial as well as barrier protection. The life of these coating systems is at best only half of the bridge design life. Furthermore, premature degradation may occur if there are flaws in the system due to improper …

The Influence Of Incorporation Of Mn On The Pitting Corrosion Performance Of Crfeconi High Entropy Alloy At Different Temperatures, H. Torbati-Sarraf, Mitra Shabani, Paul D. Jablonski, Garrett J. Pataky, A. Poursaee

Publications

The electrochemical behavior and susceptibility to pitting corrosion of CrFeCoNi and CrMnFeCoNi high entropy alloys were studied in a 0.1 M NaCl solution at temperatures ranging from 25 to 75 °C. Electrochemical measurements revealed that CrMnFeCoNi is more susceptible to oxide film breakdown and localized corrosion compared to CrFeCoNi. Post corrosion microscopic observations showed severe pitting corrosion for CrMnFeCoNi in higher temperatures compared to CrFeCoNi. Based on in-depth XPS profile measurements on the remaining oxide films, this behavior was attributed to the depletion of Cr in the oxide film and detrimental presence of Mn in the matrix solid solution of …

Simulation And Behavior Of Corrosion Deteriorated Reinforced Concrete Members, M. A. Shayanfar, Amir Safiey

Amir Safiey

Several reinforced concrete (RC) infrastructures are now crumbling from corrosion of steel bars in concrete. The paper presents the recent advancements in analytical simulation of corrosion aftereffects on behavior of RC members. The model juxtaposes the experimental findings with analytical relationships. The implementation of the model into a nonlinear finite element formulation as well as the experimental and analytical backgrounds are discussed. The abilities of the resulted program have been studied by modeling some experimental specimens showing a reasonable agreement between the analytical and experimental findings.

A New Approach For Nonlinear Finite Element Analysis Of Reinforced Concrete Structures With Corroded Reinforcements, Mohsen A. Shayanfar, Amir Safiey

Amir Safiey

A new approach for nonlinear finite element analysis of corroded reinforcements in reinforced concrete (RC) structures is elaborated in the article. An algorithmic procedure for producing the tension-stiffening curve of

RC elements taking into consideration most of effective parameters, e.g.: the rate of steel bar corrosion, bond-slip behavior, concrete cover and amount of reinforcement, is illustrated. This has been established on both experimental and analytical bases. This algorithm is implemented into a nonlinear finite element analysis program. The abilities of the resulted program have been studied by modeling some experimental specimens showing a reasonable agreement between the analytical and experimental …

Corrosion Effects On Tension Stiffening Behavior Of Reinforced Concrete, M. A. Shayanfar, M. Ghalehnovi, Amir Safiey

Amir Safiey

The investigation of corrosion effects on the tensile behavior of reinforced concrete (RC) members is very important in region prone to high corrosion conditions. In this article, an experimental study concerning corrosion effects on tensile behavior of RC members is presented. For this purpose, a comprehensive experimental program including 58 cylindrical reinforced concrete specimens under various levels of corrosion is conducted. Some of the specimens (44) are located in large tub containing water and salt (5% salt solution); an electrical supplier has been utilized for the accelerated corrosion program. Afterwards, the tensile behavior of the specimens was studied by means …

Retrofitting Of Bridge Elements Subjected To Predominantly Axial Load Using Uhpc Shell, Mahsa Farzad

FIU Electronic Theses and Dissertations

In the United States, ~30% of the ~600,000 highway bridges are categorized as structurally deficient or functionally obsolete. These bridges should be replaced or upgraded to sustain the transportation needs of the growing public and private sectors of the U.S. economy. It is not uncommon for structures to have advanced levels of corrosion-induced damage where major repair and maintenance works are required. However, the transportation infrastructure may undergo disruption during rehabilitation causing interruption to critical economic public, civil and commercial activities. This mandates the development of new techniques and materials for accelerated rehabilitation and resilience. To address this issue, a …

Ductile Corrosion-Free Self-Centering Concrete Elements, Maged Youssef, Mohamed E. Meshaly, Ahmed Elansary

Civil and Environmental Engineering Publications

Corrosion is a major factor in the deterioration of reinforced concrete (RC) structures. To mitigate this problem, steel bars can be replaced with glass-fiber-reinforced-polymer (GFRP) bars. However, the lack of ductility of GFRP-RC elements has prevented their use in many structural applications, especially in seismic areas. Superelastic shape memory alloy (SMA) bars have been proposed to be used in seismic areas because of their self-centering characteristics. Also, they have the added advantage of being corrosion resistant. This paper examines the combined use of SMA and GFRP bars to achieve ductile self-centering and corrosion-free elements. The first challenge for such a …

Flexural Behaviour Of Superelastic Shape Memory Alloy Reinforced Concrete Beams During Loading And Unloading Stages, Yamen Ibrahim Elbahy, Maged Youssef

Civil and Environmental Engineering Publications

Trend of using smart structures, which can adjust when exposed to severe unexpected loading, is increasing. One of the methods to achieve such structures relies on smart materials. For example, replacing conventional steel reinforcing bars in Reinforced Concrete (RC) structures with superelastic Shape Memory Alloy (SMA) bars significantly reduces the residual deformations caused by post-yielding behaviour. This paper provides in-depth understanding of the flexural behaviour of SMA RC beams. A sectional analysis method, which predicts the flexural behaviour of SMA RC beams during both loading and unloading stages, is adopted and validated using available experimental data. An extensive parametric study …