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Severity And Growth Evaluation Of Rail Corrugations On Sharp Curves Using Wheel/Rail Interaction, Sakdirat Kaewunruen, Steve Marich 2015 University of Birmingham

Severity And Growth Evaluation Of Rail Corrugations On Sharp Curves Using Wheel/Rail Interaction, Sakdirat Kaewunruen, Steve Marich

Sakdirat Kaewunruen

A railway network generally spans over a large distance so the structural health monitoring of such a rail infrastructure system is one of the critical challenges in rail industry practice. Especially in an underground/subway or elevated system, the facilities, resources and time period permitted for critical infrastructure inspection and maintenance is considerably limited. As a result, the automated inspection system of railway is in very high demand. Rail corrugation defect is the periodic, undulated or wave-like vertical alignment of rail surface. The wavelength and severity of rail corrugations is dependant to track structure, track geometry, traction system, rail vehicle ...


Achieving Carbon Efficiency In Construction And Maintenance Of Railway Turnouts, Crossovers And Diamonds, Sakdirat Kaewunruen, Steve Krezo, Olivia Mirza, Yapping He, Joseph M. Sussman 2015 University of Birmingham

Achieving Carbon Efficiency In Construction And Maintenance Of Railway Turnouts, Crossovers And Diamonds, Sakdirat Kaewunruen, Steve Krezo, Olivia Mirza, Yapping He, Joseph M. Sussman

Sakdirat Kaewunruen

Railway turnouts, crossovers, and diamonds are special track systems used to divert a train from a particular direction or a particular track onto other directions or other tracks. It is a structural grillage system that consists of steel rails, points, crossings, steel plates, rubber pads, insulators, fasteners, screw spikes, beam bearers (either timber, polymer, steel or concrete), ballast and formation. Usually under dynamic and high-intensity impact loading conditions, structural components of the turnout tend to have relatively short lives compared with those of ordinary open railway tracks, resulting in frequent turnout re- construction and maintenance (ranging from every 10 to ...


Rail Squats: Understand Its Causes, Severity, And Non-Destructive Evaluation Techniques, Sakdirat Kaewunruen, Makoto Ishida 2015 University of Birmingham

Rail Squats: Understand Its Causes, Severity, And Non-Destructive Evaluation Techniques, Sakdirat Kaewunruen, Makoto Ishida

Sakdirat Kaewunruen

Generally, rail squats are defined by the growth of any cracks that have grown longitudinally through the rail subsurface and some of the cracks propagating to the bottom of rails transversely have branched from initial longitudinal cracks with a depression of rail surface. The rail defects are commonly referred to as ‘squats’ when they were initiated from damage caused by rolling contact fatigue, and as ‘studs’ when they were associated with white etching layer caused by the transform from pearlitic steel due to friction heat generated by wheel sliding or excessive traction. Such rail surface defect induces wheel/rail impact ...


Resilience-Based Design Of Precast Steel-Concrete Composites For Railway Track Slabs, Sakdirat Kaewunruen, Dane WP Griffin, Olivia Mirza, Kenny Kwok 2015 University of Birmingham

Resilience-Based Design Of Precast Steel-Concrete Composites For Railway Track Slabs, Sakdirat Kaewunruen, Dane Wp Griffin, Olivia Mirza, Kenny Kwok

Sakdirat Kaewunruen

The relatively high turnover of timber sleepers (crossties in a plain track), bearers (skeleton ties in a turnout), and transoms (bridge cross beams) is responsible for producing greenhouse gas emissions 6 times greater than an equivalent reinforced concrete counterparts. This paper presents an innovative solution for the replacement of aging timber transoms installed on existing railway bridges along with the incorporation of a continuous walkway platform, which is proven to provide environmental, safety and financial benefits. Recent developments for alternative composite materials to replace timber components in railway infrastructure construction and maintenance demonstrate some compatibility issues with track stiffness as ...


Under Sleeper Pads: Field Investigation Of Their Role In Detrimental Impact Mitigation, Sakdirat Kaewunruen, Alex M. Remennikov 2015 University of Birmingham

Under Sleeper Pads: Field Investigation Of Their Role In Detrimental Impact Mitigation, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

Under sleeper pads (USPs) are the component installed under the concrete sleepers generally to improve railway track resilience. Initial development in Europe, particularly in Austria, has encouraged the adoption of the component around the world. In practice, the component has commonly been used in certain applications, mainly to moderate track stiffness in special locations such as turnouts, crossings, and level crossing. In heavy haul operation, the heavier wagons result in sturdier bogie structures, higher unsprung mass, and then higher level of wheel-rail interaction forces. Accordingly, the application of USPs to mitigate detrimental impact load consequence on track structure is presented ...


Design Of Holes And Web Openings In Railway Prestressed Concrete Sleepers, Erosha Kahawatta Gamage, Sakdirat Kaewunruen, Alex M. Remennikov 2015 University of Birmingham

Design Of Holes And Web Openings In Railway Prestressed Concrete Sleepers, Erosha Kahawatta Gamage, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

As the crosstie beam in railway track systems, the prestressed concrete sleepers (or railroad ties) are principally designed in order to carry wheel loads from the rails to the ground. Their design takes into account static and dynamic loading conditions. It is evident that prestressed concrete has played a significant role as to maintain the high endurance of the sleepers under low to moderate repeated impact loads. In spite of the most common use of the prestressed concrete sleepers in railway tracks, there have always been many demands from rail engineers to improve serviceability and functionality of concrete sleepers. For ...


Movement Of Scientists And The Production Of Aluminum, Fathi Habashi 2015 Laval University, Quebec City, Canada

Movement Of Scientists And The Production Of Aluminum, Fathi Habashi

Fathi Habashi

Travelling scientists certainly have contributed to advancing knowledge by communicating their observations to others. Famous professors attract students from different countries to study in their institutions and the interaction among these students is of immense importance in the diffusion of knowledge. The invention of a process for the production of aluminum is an example.


Predictive Modeling Of Oxygen Transmission Through Micro-Perforations For Packaging Applications, Ayman Abdellatief, Bruce A. Welt, Jason Butler, Eric McLamore, Arthur Teixeira, Sanjay Shukla 2015 University of Florida

Predictive Modeling Of Oxygen Transmission Through Micro-Perforations For Packaging Applications, Ayman Abdellatief, Bruce A. Welt, Jason Butler, Eric Mclamore, Arthur Teixeira, Sanjay Shukla

Journal of Applied Packaging Research

Methods for creating precise perforations in respiring produce packaging are being increasingly adopted. Knowledge of oxygen transfer through perforated packaging and oxygen distribution in packages is necessary for successful packaging design of fresh produce. An approach to modeling perforated packaging performance was developed using a cylindrical chamber with precision perforations using Fick’s second law. The model was simulated using two techniques including Finite Element Method (FEM) using commercially available software and Finite Volume Method (FVM) through programming. Perforations were approximated as a source term in the second method. Both simulation techniques showed trends similar to experimental data.


Impact Responses Of Prestressing Tendons In Railway Concrete Sleepers In High Speed Rail Environments, Sakdirat Kaewunruen, Alex M. Remennikov 2015 University of Birmingham

Impact Responses Of Prestressing Tendons In Railway Concrete Sleepers In High Speed Rail Environments, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

Prestressed concrete sleepers (or railroad ties) are designed in order to carry and transfer the wheel loads from the rails to the ground and are installed as the crosstie beam support in railway track systems. They are subjected to impact loading conditions that are resulted from train operations over wheel or rail abnormalities, such as flat wheels, dipped rails, crossing transfers, rail squats, corrugation, etc. The magnitude of the shock load relies on various factors such as axle load, types of wheel/rail imperfections, speeds of vehicle, track stiffness, etc.

This paper demonstrates the development of finite element modelling to ...


Characterizing Water As Gap Fill For Double Glazing Units, Bright Adu 2015 Western Kentucky University

Characterizing Water As Gap Fill For Double Glazing Units, Bright Adu

Masters Theses & Specialist Projects

The use of sunlight has always been a major goal in the design and operation of commercial buildings to minimize electrical consumption of artificial lighting systems. Glazing systems designed to allow optimal visible light transmission also allow significant unwanted direct solar heat gain caused by infrared light. Conversely, glazing systems that are designed to reflect unwanted direct solar heat gain significantly reduce the transmittance of visible light through windows. The goal of this research was to characterize the performance of water as gap-fill for double-glazing units in eliminating the compromises that exist in current glazing systems with respect to light ...


Dynamic Simulation And Neuromuscular Control Of Movement: Applications For Predictive Simulations Of Balance Recovery, Misagh Mansouri Boroujeni 2015 University of Tennessee - Knoxville

Dynamic Simulation And Neuromuscular Control Of Movement: Applications For Predictive Simulations Of Balance Recovery, Misagh Mansouri Boroujeni

Doctoral Dissertations

Balance is among the most challenging tasks for patients with movement disorders. Study and treatment of these disorders could greatly benefit from combined software tools that offer better insights into neuromuscular biomechanics, and predictive capabilities for optimal surgical and rehabilitation treatment planning. A platform was created to combine musculoskeletal modeling, closed-loop forward dynamic simulation, optimization techniques, and neuromuscular control system design. Spinal (stretch-reflex) and supraspinal (operational space task-based) controllers were developed to test simulation-based hypotheses related to balance recovery and movement control. A corrective procedure (rectus femoris transfer surgery) was targeted for children experiencing stiff-knee gait and how this procedure ...


Energy Selective Neutron Imaging For The Characterization Of Polycrystalline Materials, Robin Woracek 2015 University of Tennessee - Knoxville

Energy Selective Neutron Imaging For The Characterization Of Polycrystalline Materials, Robin Woracek

Doctoral Dissertations

This multipart dissertation focuses on the development and evaluation of advanced methods for material testing and characterization using neutron diffraction and imaging techniques. A major focus is on exploiting diffraction contrast in energy selective neutron imaging (often referred to as Bragg edge imaging) for strain and phase mapping of crystalline materials. The dissertation also evaluates the use of neutron diffraction to study the effect of multi-axial loading, in particular the role of applying directly shear strains from the application of torsion. A portable tension-torsion-tomography loading system has been developed for in-situ measurements and integrated at major user facilities around the ...


Phase Dynamics Of Locset Control Methodology, Brendan Neschke 2015 University of Tennessee - Knoxville

Phase Dynamics Of Locset Control Methodology, Brendan Neschke

Masters Theses

Single-mode fiber amplifiers produce diffraction-limited beams very efficiently. Maximum beam intensity requires that an array of these amplifiers have their beams coherently combined at the target. Optical path differences and noise adversely affect beam quality. An existing closed loop phase control methodology, called the locking of optical coherence by single-detector electronic-frequency tagging (LOCSET), corrects phase errors in real time by electronically detecting path length differences and sending signals to lithium niobate phase adjusters. Broadening the line-width using “jitter” of the input signal can increase the output power of an individual amplifier by suppressing nonlinearity. The system dynamics of LOCSET are ...


Impact Of Fuel Rod Coatings On Reactor Performance And Safety, Ian Robert Stewart 2015 University of Tennessee - Knoxville

Impact Of Fuel Rod Coatings On Reactor Performance And Safety, Ian Robert Stewart

Masters Theses

This study evaluates the use of a ceramic coating on the Zr-alloy cladding within a PWR using four ceramic compounds of 5 and 10 micron thicknesses: ZrO2, TiAlN, Ti2AlC, and Ti3AlC2. The film’s impact is assessed for variation on: reactivity, fuel cycle length, maximum temperature, film’s roughness, and transient conditions. The reactivity is analyzed using the following methods: change in the multiplication factor (k) each film introduces to the system using the ABH method, and Monte Carlo software (MCNP). Both methods are in good agreement, yielding less than half a percent change from a reference, no-film fuel pin ...


Development Of An Efficient Data Processing Procedure For The Prediction Of Cleavage Fracture In Reactor Pressure Vessel Steels Using The J-A2 Method, Phoebe E. Fogelman 2015 University of Tennessee - Knoxville

Development Of An Efficient Data Processing Procedure For The Prediction Of Cleavage Fracture In Reactor Pressure Vessel Steels Using The J-A2 Method, Phoebe E. Fogelman

University of Tennessee Honors Thesis Projects

No abstract provided.


Finite Element Modelling Of Modular Precast Composites For Railway Track Support Structure – A Battle To Save Sydney Harbour Bridge, Dane Griffin, Olivia Mirza, Kenny Kwok, Sakdirat Kaewunruen 2015 UWS

Finite Element Modelling Of Modular Precast Composites For Railway Track Support Structure – A Battle To Save Sydney Harbour Bridge, Dane Griffin, Olivia Mirza, Kenny Kwok, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Railway networks in Australian alone require replacing a large amount of aging timber components in excess of 280,000 m3 per year. The replacement of timber track components is responsible for producing greenhouse gas emissions 6 times greater than equivalent reinforced concrete counterparts. Sydney Harbour Bridge presently experiences similar problem. A feasibility study to develop an innovative solution for the replacement of aging timber transoms installed on the Sydney Harbour Bridge was conducted to evaluate environmental, safety and financial benefits. The development of alternative composite structure to replace the timber components overcomes some potential compatibility issues with track stiffness as ...


Fluids Dynamics & Heat Transfer Lab Design, Bruce Gerry 2015 University of Southern Maine

Fluids Dynamics & Heat Transfer Lab Design, Bruce Gerry

Thinking Matters

This project consists of the designing, building, and creation of instruction manuals for several labs in fluids and heat transfer fields. Labs for these fields tend to be large and hard to simulate as physical models. This project will solve that problem by creating simulations: in solidworks. Not only will simulations in solidworks make some concepts possible to demonstrate but, it will also expose students to useful software that will be used in the workforce.


An Operational Performance And Safety Comparison Of Roundabouts Vs. Traditional Intersections, Vincent Spahr 2015 University of Dayton

An Operational Performance And Safety Comparison Of Roundabouts Vs. Traditional Intersections, Vincent Spahr

Honors Theses

As the modern roundabout becomes a more popular intersection alternative in the United States, the ability of the roundabout to effectively manage traffic and to do so safely is on the forefront of engineering concerns. Despite decades of international success and credibility, regions throughout the U.S. have been hesitant to implement roundabouts in place of more traditional intersections. This case study of a series of intersections in Dublin, OH assesses the operational performance of roundabouts as it compares to that of their stop-controlled and signalized counterparts and analyzes historical crash data to evaluate the safety of the various intersection ...


Implications Of Heterogeneity In The Shock Wave Propagation Of Dynamically Shocked Materials, Jeffrey W. LaJeunesse 2015 Marquette University

Implications Of Heterogeneity In The Shock Wave Propagation Of Dynamically Shocked Materials, Jeffrey W. Lajeunesse

Master's Theses (2009 -)

The field of shock physics as a whole has only recently begun to pay particular attention to modeling heterogeneous materials under shock loading. These materials are important because of their practicality in terms of creating stronger, more shock resistant materials. To understand why they absorb shock impact energy better than homogeneous materials means that the small-scale processes that occur during the shock loading of these heterogeneous materials needs to be understood. Recent computational experiments, called mesoscale simulations, have shown that explicitly incorporating small-scale heterogeneous features into hydrocode simulations allows the bulk shock response of the heterogeneous material to be observed ...


Development Of A Metal-Printing 3d Printer At The University Of North Dakota, Benjamin Kading, Michaela Kegley, Tiana Delzer, Jeremy Straub, Scott Kerlin 2015 SelectedWorks

Development Of A Metal-Printing 3d Printer At The University Of North Dakota, Benjamin Kading, Michaela Kegley, Tiana Delzer, Jeremy Straub, Scott Kerlin

Jeremy Straub

Three-dimensional (3D) printing is being used for numerous applications: from consumer hobbies to the development of aircraft parts. However, inexpensive 3D printers have been constrained in material selection to plastic. These printer use the fused deposition modeling (FDM) method of printing, which is a relatively new technology that utilizes computer numerical control (CNC) techniques to deposit melted material at specific places. Other methods, for example, include laser sintering and stereolithography. With 3D printing, layers are stacked upon each other and via this compilation of layers, a 3D object is formed. Currently there are a variety of materials that can be ...


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