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Application Of Wavelet Analysis And Random Field In Integrity Management Of Pipelines Containing Dents And Corrosions, Junxiong Lin

Electronic Thesis and Dissertation Repository

Metal loss corrosions and dents are two major threats to the integrity of oil and natural gas pipelines. In the pipeline industry, the Fitness-For-Service (FFS) assessment is commonly employed for pipelines containing these defects. However, FFS assessment usually assumes that a defect has a simple shape, and such a simplification may significantly affect the accuracy of the assessment. Therefore, retaining the actual shapes of defects and incorporating them into the FFS assessment can improve assessment accuracy. The main objective of the present thesis is to extract key information about the sizes, directions, and shapes of corrosions and dents from the …

Parametric Analysis And Enhancement Of The Burst Capacity Model For Composite-Repaired Corroded Pipelines, Rodrigo Silva Silva-Santisteban

Electronic Thesis and Dissertation Repository

One of the main causes of pipeline failures is corrosion, which leads to a localized loss of the pipe wall thickness and hence compromises the capacity of the pipeline. Composite repair is a method to rehabilitate corroded pipelines. Design codes such as ASME PCC-2 are commonly used to design the repair thickness. As the predictive accuracy to determine the burst capacity of a composite repaired pipeline with existing models is generally poor, the main objective of the present thesis is to provide insights on the parameters that affect the burst capacity and propose improvements to the prediction of burst capacity …

Towards Smart And Cost-Effective Bridge Infrastructure Monitoring Systems, Premjeet Singh

Electronic Thesis and Dissertation Repository

Bridge health monitoring (BHM) has recently gained significant interest worldwide in the inspection and maintenance of aging bridge infrastructure in the era of climate change and adverse weather conditions. However, extensive datasets resulting from these monitoring systems require appropriate tools to diagnose the data systematically under various operating conditions of bridges, leading to expensive and time intensive BHM strategies. To mitigate this challenge, a smart and cost-effective bridge infrastructure management system is of paramount need in today’s world. This thesis aims to develop a suite of cost-effective bridge management strategies by employing limited and mobile sensing technology and addressing their …

Experimental Evaluation Of Abl And Downburst Wind Loads On An Elevated Building, Kate Current

Electronic Thesis and Dissertation Repository

Elevated low-rise buildings are vulnerable to cladding damage underneath the structure due to extreme winds and the absence of proper wind loading codes and standards such as the National Building Code of Canada (NBCC). The space between the ground and the horizontal base surface of an elevated structure affects its aerodynamics differently compared to a ground-mounted structure. Despite the widespread use of elevated low-rise buildings, there is still limited understanding of the wind interaction across building surfaces for different stilt heights and wind types. This research aims to evaluate the impact of atmospheric boundary layer (ABL) and downburst wind loads …

Simplified Modeling Of Bonded Prestressed High Strength Concrete Girders During Fire Exposure, Yi Mao

Electronic Thesis and Dissertation Repository

To evaluate the behavior of structures exposed to fire and estimate their structural fire resistance, engineers need design tools to overcome the complexities associated with structural analysis during fire exposure. These complexities include the uneven distribution of temperature within the structural elements and the deterioration in material properties. The current study introduces a simplified numerical model to evaluate the flexural behavior of bonded prestressed high-strength concrete sections exposed to fire. The model starts by predicting the temperature distribution within a structural element using 2-D finite difference analysis. It then uses one-dimensional sectional analysis to estimate the section behavior. The numerical …

Fire-Resistance Testing Procedures For Construction Elements—A Review, Shashikant Chaturvedi, Ajitanshu Vedrtnam, Maged A. Youssef, Martin T. Palou, Gonzalo Barluenga, Kishor Kalauni

Civil and Environmental Engineering Publications

Fire accidents are a significant risk to human life and civil infrastructure. As a countermeasure, the regulatory bodies of different countries have established standards for evaluating the performance of construction elements during fire exposure. ISO 834 is the globally accepted fire-resistance testing standard. Other standards include ASTM E119, BS 476, IS 3809, JIS A 1304, AS 1503, EN 1363, and GB/T 9978, which are utilized by the US, Britain, India, Japan, Australia, Europe, and China, respectively. This article presents a summary and comparison of the fire-resistance testing standards. In reality, standard tests for isolated structural members may not efficiently portray …

An Explicit Model For Simplified Flutter Analysis Of Long-Span Bridges, Tibebu Hunegn Birhane

Electronic Thesis and Dissertation Repository

The collapse of the First Tacoma Bridge in 1940 at a wind speed of about 18m/s triggered the need to recognize aerodynamic stability as a design constraint for long-span bridges. The advancement in understanding and modeling of dynamic wind effects has played a significant role in the realization of long-span bridges with a clear span of up to 2 km. However, the need to span longer, the risk of windstorms exceeding the strongest recorded in the past, and consequently, the quest for optimized design solutions continue to evolve.

A rigorous nature of aerodynamic stability analysis techniques poses a challenge to …

Seismic Performance Of Ductile Corrosion-Free Reinforced Concrete Frames, Mohamed Meshaly, Maged A. Youssef, Ahmed Elansary

Civil and Environmental Engineering Publications

Corrosion of steel bars is the main cause of the deterioration of reinforced concrete (RC) structures. To avoid this problem, steel rebars can be replaced with glass-fiber-reinforced-polymer (GFRP). However, the brittle behaviour of GFRP RC elements has limited their use in many applications. The use of shape memory alloy (SMA) and/or stainless steel (SS) rebars can solve this problem, because of their ductile behaviour and corrosion resistance. However, their high price is a major obstacle. To address issues of ductility, corrosion, and cost, this paper examines the hybrid use of GFRP, SS, and SMA in RC frames. The use of …

Structural Performance Of Single-Skin Glass Façade Systems Exposed To Fire, Mohamed Badr, Maged A. Youssef, Salah El-Din F. El-Fitiany, Ajitanshu Vedrtnam

Civil and Environmental Engineering Publications

Purpose

Understanding the structural performance of external glass curtain walls (façades) during fire exposure is critical for the safety of the occupants, as their failure can lead to fire spread throughout the entire building. This concern is magnified by the recent increase in fire incidents and wildfires. This paper presents the first simplified technique to model single skin façades during fire exposure, and, then utilizes it to examine the structural behaviour of vertical, inclined, and oversized façade panels.

Design/methodology/approach

The proposed technique is based on conducting simplified heat transfer calculations, and, then utilizing a widely used structural analysis software to …

Performance And Ultimate Limit State Of Large-Span Soil-Steel Structures, Kareem Embaby

Electronic Thesis and Dissertation Repository

This thesis investigates the structural behavior and soil-structure interaction mechanism of large-span soil-steel structures utilizing steel plates with the deepest corrugation profile, 500 mm X 237 mm. The world’s largest-span soil-steel bridge, with a span of 32.40 m, was constructed using 12 mm thick steel plates with the deepest corrugation profile and was instrumented extensively to monitor the displacements and straining actions of the steel structure. Lateral reinforcement steel mesh was attached to the steel structure and the ends of the structure were strengthened by circumferential reinforced concrete collars. Three-dimensional (3D) nonlinear finite element (FE) model was conducted and validated …

Hydration Kinetics, Microstructure, And Mechanical Strength Development Of Cement-Based Composites Incorporating Phase Change Materials, Afshin Marani

Electronic Thesis and Dissertation Repository

The research conducted in this thesis investigates the effects of phase change materials (PCMs) on the hydration kinetics and strength development of cement-based composites using extensive experimental and numerical analyses. Purposefully, the effect of microencapsulated PCMs (MPCMs) on the strength development of cement-based mortars and concretes was evaluated using powerful machine learning models trained with the largest available experimental data. Furthermore, a novel ternary machine learning approach was proposed to optimize the mixture design of mortars and concretes based on the thermos-physical properties of the MPCMs. The results obtained from machine learning simulations suggest the assessment of the effects of …

Effect Of Structural Nonlinearities On Flutter Of Cable-Supported Bridges, Sébastien Maheux

Electronic Thesis and Dissertation Repository

It is well known that cable-supported bridges, like suspension bridges and cable-stayed bridges, are structures that are highly sensitive to wind. This is why there has been an important research effort over the past decades on aeroelastic instability phenomena in bridges like flutter. This has allowed the safe design of long-span bridges with respect to wind effects. Nonetheless, the analysis methods that have become the norm in the field of bridge engineering, such as flutter analysis and wind tunnel tests, rely on some simplifications to facilitate analysis. For example, they assume a linear structural behavior of the bridge structure. Therefore, …

Residual Axial Behavior Of Restrained Reinforced Concrete Columns Damaged By A Standard Fire, M. Monir M. Ajan Alhadid, Maged A. Youssef

Civil and Environmental Engineering Publications

A simplified procedure to predict the residual axial capacity and stiffness of both rectangular and circular reinforced concrete (RC) columns after exposure to a standard fire provides the means to replace the current descriptive methods. The availability of such a procedure during the design phase provides engineers with the flexibility to come up with better designs that ensure safety. In this paper, finite difference heat transfer and sectional analysis models are combined to determine the axial behavior of RC columns with various end-restraint conditions at different standard fire durations. The influence of cooling phase on temperature distribution and residual mechanical …

Influence Of Natural Fire Development On Concrete Compressive Strength, Robert T. Kuehnen, Maged A. Youssef, Salah El-Din F. El-Fitiany

Civil and Environmental Engineering Publications

With increasing acceptance of performance-based design principles in the field of fire safety, it is imperative to accurately define the behaviour of materials during fire exposure. Real-world fire events, otherwise referred to as natural fires, are defined by four characteristics: heating rate, maximum temperature, exposure duration, and cooling rate. Each of these four characteristics influences concrete’s behaviour in a different manner. In this paper, the available experimental work for concrete, tested at elevated temperatures, is examined to identify the influence of the four natural fire characteristics on concrete compressive strength. This review focuses on normal strength concrete tests only, omitting …

Seismic Performance Of Hybrid Corrosion-Free Self-Centering Concrete Shear Walls, Emad A. Abraik, Maged A. Youssef, Salah El-Din F. El-Fitiany

Civil and Environmental Engineering Publications

Reinforced concrete (RC) walls are extensively used in high-rise buildings to resist lateral loads, while ensuring an adequate level of ductility. Durability problems, including corrosion of conventional steel reinforcements, necessitate exploring alternative types of reinforcement. The use of glass fiber reinforced polymer (FRP) bars is a potential solution. However, these bars cannot be used in seismic applications because of their brittleness and inability to dissipate seismic energy. Superelastic shape memory alloy (SMA) is a corrosion-free material with high ductility and unique self-centering ability. Its high cost is a major barrier to use in construction projects. The clear advantage of utilizing …

Behaviour Of Transmission Line Conductors Under Tornadoes, Dingyu Yao

Electronic Thesis and Dissertation Repository

Transmission line (TL) structure failures caused by tornadoes have been observed in multiple countries around the globe. The objective of this study is to develop an accurate load case that can simulate the critical tornado forces transmitted from the TL conductors to the towers. In order to achieve the goal, three different tornado wind fields, which were previously developed using computational fluid dynamic simulations, are considered. The tornado wind field provides the most critical forces on the TL conductors is determined and considered to obtain the critical load cases. Using the critical wind field, parametric studies are conducted to identify …

Behavior Of Wind Turbine Towers And Blades Under Tornado Wind Fields, Mohamed Abugazia

Electronic Thesis and Dissertation Repository

The installation rate of wind turbines around the world is increasing significantly. Therefore, wind turbine farms are constructed in plentiful wind resources areas that put a considerable number of wind turbine towers under severe wind conditions. As a result, failures due to unexpected wind loads on either the blades or the tower are increasing. In addition, wind turbines are designed to resist synoptic wind loads as per the current guidelines, which do not consider high-intensity wind (HIW) events such as tornadoes. The built-in-house numerical code “HIW-WT” has been developed in this study to model wind turbines under three-dimensional wind fields …

Effects Of The Soil Spatial Variability On Pipelines, Jose Luis Espinosa Mendez

Electronic Thesis and Dissertation Repository

Pipelines are the safest and most efficient way to transport large volumes of oil and gas from extraction fields, to refineries, industry and home consumption. Extensively used to transport fluids over long distances, pipelines may pass through terrain features exposed to geohazards. The performance of buried pipelines in areas subjected to ground displacements constitute a criterion for design, assessment and management of gas pipelines, to ensure public, environment and property safety in a cost-effective manner. Modern surveying and sampling techniques allow for better geotechnical characterization of ground movements and the variability of the soil properties with confidence. The statistical data …

Effect Of Non-Uniform Temperature Exposure On The Out-Of-Plane Bending Performance Of Ordinary Laminated Glass Panels, Maged A. Youssef, Ajitanshu Vedrtnam, Chiara Bedon, Shashikant Chaturvedia

Civil and Environmental Engineering Publications

Among the open design issues for structural laminated glass (LG) elements, their mechanical performance during fire exposure stands as a safety concern. This issue is the focus of this paper. An experimental investigation is conducted to evaluate the effect of non-uniform thermal gradients on the out-of-plane bending capacity of standard LG specimens. The pre-fracture, cracking, and post-fracture performances of LG panels were examined using a three-point bending setup. The bending tests were carried out on un-heated LG samples and heated samples, which were either hot or cooled down. The reliability of available analytical and numerical methods to predict the out-of-plane …

Experimental Simulation Of Tornado-Like Vortices And Their Impact On High-Rise Buildings, Arash Ashrafi

Electronic Thesis and Dissertation Repository

One of the most crucial research areas in wind engineering is tornadoes due to the widespread damages to infrastructure and the environment in North America and other parts of the world. The proper scaling of tornadoes in experimental facilities, generating tornado-like vortices (TLVs) is, therefore, an essential part of evaluating tornado-indued damages on engineered buildings. The capability of producing TLVs of length scales in the range between 1:300 and 1:150 inside the Wind Engineering, Energy and Environment (WindEEE) Dome at Western University has already been demonstrated using only one mode of the full potential of this simulator. A new mode …

Structural Performance Of Glass Façades Exposed To Fire, Mohamed Badr

Electronic Thesis and Dissertation Repository

Glass façades are commonly used in the modern construction industry. The thesis starts by providing a general background about glass façades, their design criteria, and related previous research studies. The common concern among the previous studies was the inadequate performance of glass façades during fire incidents, which accelerates the spread and severity of the fire. This concern is magnified by the recent worldwide increase in wildfires. Thus, it is critical for engineers to be able to assess the structural performance of glass façades at elevated temperatures. The thesis addresses this need by presenting a simplified technique to model single skin …

Ductility And Overstrength Of Shape-Memory-Alloy Reinforced-Concrete Shear Walls, Emad A. Abraik, Maged A. Youssef

Civil and Environmental Engineering Publications

The unique properties of superelastic shape-memory-alloy (SMA) bars have motivated researchers to investigate their use as reinforcing bars for concrete elements. They were found to decrease seismic residual deformations, while increasing seismic inelastic deformations. This characteristic deformation behaviour requires an assessment of the seismic design parameters of SMA reinforced concrete walls. This paper addresses this requirement by evaluating their ductility and overstrength factors. A total of 972 walls were analyzed under a quasi-static lateral load. Suitable values for the overstrength and ductility factors were estimated for two proposed locations of SMA bars. FEMA P695 was then utilized to evaluate the …

Simplified Structural Analysis Of Framed Ordinary Non-Tempered Glass Panels During Fire Exposure, Amer Sabsabi, Maged A. Youssef, Salah El-Din F. El-Fitiany, Ajitanshu Vedrtnam

Civil and Environmental Engineering Publications

Ordinary non-tempered glass is one of the most widely used materials in the construction industry. Knowing its fire resistance is essential to ensure the safety of emergency personnel as its failure increases the oxygen supply and causes a rapid spread of the fire (flashover phenomenon). Existing approaches for evaluating the structural fire safety of glass façades require expensive experimental tests and/or extensive knowledge of Finite Element modeling. This paper provides a simplified, rational, and reliable approach to assess the structural capacity of ordinary glass panels during fire exposure. A simplified method is developed to predict the temperature difference between …

Implication Of City Growth On Wind-Induced Loads For Cladding And Structural Design, Hadil M. Abdallah

Electronic Thesis and Dissertation Repository

As cities grow, the urban topology changes in density resulting in continuous variations in wind flow. The interaction of flow with this changing surrounding environment drives the aerodynamics to become more complex and varying, subjecting the building to significant changes in wind-induced-loads both on structural and non-structural elements. In this study, a series of boundary layer wind tunnel tests are conducted to investigate the impact of city growth on cladding and structural loading by using a typical tall building adopted from the Commonwealth Advisory Aeronautical Council (CAARC) building model. The city growth is represented by five different generic surrounding configurations, …

Machine Learning Prediction Of Structural Response For Reinforced Concrete Members Under Blast Loading, Monjee Almustafa

Electronic Thesis and Dissertation Repository

With increasing accidental and intentional explosions and blast events inflicting life loss and economic damage to civil infrastructure, greater attention is given to the analysis and design of blast-resistant structures. Accordingly, this thesis introduces state-of-the-art machine learning models dedicated to predicting the structural behavior of various reinforced concrete (RC) members under blast loading, including slabs, columns, and beams. Moreover, extended prediction models were developed for RC members that employ fiber-reinforced polymer (FRP) retrofitting and steel fiber-reinforced concrete as blast mitigation strategies. For each model, extensive validation was conducted through statistical performance measures and comparisons to existing prediction methods. Additionally, feature …

Burst Capacity Evaluation Of Corroded Pipelines Under Internal Pressure And Internal Pressure Combined With Longitudinal Compression, Shulong Zhang

Electronic Thesis and Dissertation Repository

Central to the design and integrity assessment of oil and gas transmission pipelines is to accurately evaluate their pressure containment capacities, i.e. burst capacities. Corrosion defects threaten the structural integrity of pipelines as they cause thinning of the pipe wall and therefore reduce the burst capacity. Corroded in-service pipelines may be subjected to longitudinal compression resulting from, for example, ground movement or formation of free spans, in addition to internal pressures. The main objective of the research reported in this thesis is to facilitate Fitness-For-Service (FFS) assessment of corroded pipelines.

The first study investigates the conservatism associated with the rectangular …

Seismic Performance Of Rc Beam-Column Edge Joints Reinforced With Austenite Stainless Steel, C Xu, Moncef L. Nehdi, Maged A. Youssef, L. V. Zhang

Civil and Environmental Engineering Publications

Using stainless steel (SS) reinforcement can mitigate colossal corrosion damage inflicted to reinforced concrete (RC) structures worldwide. However, there is still dearth of studies on the seismic behavior of SS-RC structures. Hence, quasi-static tests were carried out in this study to explore the seismic performance of three RC frame edge joint specimens reinforced with SS having strength grade of 500 and one control RC specimen made with grade 400 normal steel. RC edge frame joints reinforced with ordinary steel and SS exhibited similar bending-shear failure patterns at the beam root. The load bearing capacity of the SS-RC edge fame joint …

Towards Multiclass Damage Detection And Localization Using Limited Vibration Measurements, Sandeep Sony

Electronic Thesis and Dissertation Repository

Traditional vibration-based damage detection methods provide structural health information based on their measured data (i.e., acceleration and displacement response). Over the last few decades, various model-based and time-frequency methods have shown great promises for damage identification and localization. However, the existing methods are unable to perform satisfactorily in many situations, including the presence of limited sensor measurements and training data, detection of minor and progressive damage, and identification of multiclass damage, creating constraints to make them free of user-intervention and implemented using the modern sensors. The main objective of this thesis is to develop algorithms capable of damage identification and …

Finite Element Analyses And Random Field Modeling Of Naturally Corroded Underground Energy Pipelines, Ji Bao

Electronic Thesis and Dissertation Repository

Metal-loss corrosion is one of the major threats to the integrity of oil and natural gas pipelines. The Fitness-For-Service (FFS) assessment is commonly carried out to demonstrate the integrity of the corroded pipelines. The naturally occurring corrosions on the external surfaces are irregularly shaped three-dimensional features. Due to the geometric complexity of the natural corrosion features, the research of FFS assessment in the previous studies always employed the pipe segments containing artificially induced corrosion features. However, since artificial features are in general regular-shaped, e.g. cubic or semi-ellipsoidal, they do not capture geometric characteristics of naturally occurring corrosions. The thesis develops …

Machine Learning Prediction Of Shear Capacity Of Steel Fiber Reinforced Concrete, Wassim Ben Chaabene

Electronic Thesis and Dissertation Repository

The use of steel fibers for concrete reinforcement has been growing in recent years owing to the improved shear strength and post-cracking toughness imparted by fiber inclusion. Yet, there is still lack of design provisions for steel fiber-reinforced concrete (SFRC) in building codes. This is mainly due to the complex shear transfer mechanism in SFRC. Existing empirical equations for SFRC shear strength have been developed with relatively limited data examples, making their accuracy restricted to specific ranges. To overcome this drawback, the present study suggests novel machine learning models based on artificial neural network (ANN) and genetic programming (GP) to …