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Numerical Investigation Of Heat Generation And Accumulation Contributing To Elevated Temperature In Msw Landfills, Alborz Fathinezhad Nov 2022

Numerical Investigation Of Heat Generation And Accumulation Contributing To Elevated Temperature In Msw Landfills, Alborz Fathinezhad

LSU Doctoral Dissertations

Landfills are complex geostructures which contains organic and inorganic municipal, and in some cases industrial, wastes and are expected to remain operational for long times. Due to the complex nature of physical, chemical, biological, and thermal reactions that carry on within the depths of a landfill, unexpected incidents such as elevated temperatures could become inevitable. While uncommon to happen, elevated temperatures cause health and environmental issues such as odors, rapid settlements, slope instabilities. In addition, elevated temperatures can negatively impact engineered components in composite bottom liners, cover systems, leachate collection, and gas extraction and recovery systems.

Air intrusion into municipal …


Modelling And Simulation Of Nonstationary Non-Gaussian Wind Speed And Wind Pressure Coefficients, Minyu Xiao Aug 2022

Modelling And Simulation Of Nonstationary Non-Gaussian Wind Speed And Wind Pressure Coefficients, Minyu Xiao

Electronic Thesis and Dissertation Repository

The time series of the wind speed from hurricane and downburst events can exhibit nonstationary non-Gaussian characteristics. Moreover, the time series of the wind pressure for a stationary wind may not be Gaussian. This thesis is focused on analyzing, characterizing, and simulating nonstationary/stationary Gaussian/non-Gaussian of wind speed and wind pressure coefficients by using time-frequency transform techniques such as the S-transform (ST) and discrete orthonormal S-transform (DOST). It is shown that by removing the mean of downburst winds, the multivariate nonstationary downburst wind speed processes can be efficiently decomposed and simulated by applying ST and DOST. It was also found that …


An Improved Polynomial Chaos Expansion Based Response Surface Method And Its Applications On Frame And Spring Engineering Based Structures, Mhd A. Hafez Jun 2022

An Improved Polynomial Chaos Expansion Based Response Surface Method And Its Applications On Frame And Spring Engineering Based Structures, Mhd A. Hafez

ETD Archive

In engineering fields, computational models provide a tool that can simulate a real world response and enhance our understanding of physical phenomenas. However, such models are often computationally expensive with multiple sources of uncertainty related to the model’s input/assumptions. For example, the literature indicates that ligament’s material properties and its insertion site locations have a significant effect on the performance of knee joint models, which makes addressing uncertainty related to them a crucial step to make the computational model more representative of reality. However, previous sensitivity studies were limited due to the computational expense of the models. The high computational …


Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari Dec 2021

Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari

Electronic Theses and Dissertations

Extrusion-based 3D printing of thermoplastic polymer composites manufactures parts that have nonhomogenous, orthotropic, and process-dependent macro-scale material properties. As a part of the dissertation, research works were carried out to: • improve the interlayer mechanical properties and reduce the orthotropy, • use experimentally homogenized orthotropic material properties to numerically model the mechanical behavior of the non-homogenous orthotropic 3D printed parts, • create an efficient numerical thermal model to predict the process-dependent thermal history of the 3D printed part, and • aid the manufacturing process by selecting a suitable set of processing parameters based on a simplified sequentially coupled thermomechanical model. …


Uncertainties In Internal Pressure Of Oil Pipelines And Implications For The Reliability Analysis, Yue Liu Aug 2021

Uncertainties In Internal Pressure Of Oil Pipelines And Implications For The Reliability Analysis, Yue Liu

Electronic Thesis and Dissertation Repository

The internal pressure is the most important operational load for oil and gas pipelines. The maximum operating pressure (MOP) is the maximum pressure the pipeline is qualified to be operated according to a given standard. In deterministic fitness-for-service (FFS) assessment of in-service pipelines containing flaws such as corrosion defects and cracks, the remaining pressure containment capacity of the pipeline is evaluated and compared with MOP multiplied by a factor of safety to determine if immediate rehabilitation actions for the pipeline are necessary. However, the actual internal pressure of an in-service pipeline is however uncertain and fluctuates with time. Due to …


Assessing The Impact Of Health Benefits And Carbon Footprint In Student Parking Decisions At A University Campus, Emiliano Ruiz Aug 2021

Assessing The Impact Of Health Benefits And Carbon Footprint In Student Parking Decisions At A University Campus, Emiliano Ruiz

Open Access Theses & Dissertations

In the student parking location problem, traditionally, the parking permit cost, the last-mile travel time, and the ease of finding an available parking stall are the only decision criteria driving permit purchases. However, a studentâ??s choice of parking location has associated walking health benefits and sustainability impacts. These impacts are related to the walking distance from the parked vehicle to the final destination on campus, in addition to the location effect on the carbon footprint of a vehicle-trip taken to campus. As such, this Thesis examined a multi-criteria decision approach to a university studentâ??s choice of parking location. This approach …


A Simulation Framework For Traffic Safety With Connected Vehicles And V2x Technologies, Md Abu Sayed May 2021

A Simulation Framework For Traffic Safety With Connected Vehicles And V2x Technologies, Md Abu Sayed

Theses and Dissertations

With the advancement in automobile technologies, existing research shows that connected vehicle (CV) technologies can provide better traffic safety through Surrogate Safety Measure (SSM). CV technologies involves two network systems: traffic network and wireless communication network. We found that the research in the wireless communication network for CV did not interact properly with the research in SSM in transportation network, and vice versa. Though various SSM has been proposed in previous studies, a few of them have been tested in simulation software in limited extent. On the other hand, A large body of researchers proposed various communication architecture for CV …


Reveal Wind Loading Of Tornadoes And Hurricanes On Civil Structures Towards Hazard-Resistant Design, Ryan Honerkamp Jan 2021

Reveal Wind Loading Of Tornadoes And Hurricanes On Civil Structures Towards Hazard-Resistant Design, Ryan Honerkamp

Doctoral Dissertations

"Extreme winds impacting civil structures lead to death and destruction in all regions of the world. Specifically, tornadoes and hurricanes impact communities with severe devastation. On average, 1200 tornadoes occur in the United States every year. Tornadoes occur predominantly in the Central and Southeastern United States, accounting for an annual $1 billion in economic losses, 1500 injuries, and 90 deaths. The Joplin, MO Tornado in 2011 killed 161 people, injured more than 1000, destroyed more than 8000 structures, and caused $2.8 billion of property loss. Hurricanes occur predominantly on the United States East coast regions and along the coast of …


Optical Fiber Based Integrity Test Of Civil Engineering Materials: Numerical Analysis, Ruoyu Zhong Jan 2020

Optical Fiber Based Integrity Test Of Civil Engineering Materials: Numerical Analysis, Ruoyu Zhong

Masters Theses

“Major advancement in Civil Engineering cannot be accomplished without the help of sensors. Among different types of sensors, fiber-optic sensor is known for its light weight, high accuracy, resolution, immunity to electromagnetic interference, and resistance to harsh environment. This research mainly focuses on fiber-optic sensor application on concrete structures as temperature sensor. Thermal Integrity Profiling (TIP) is a non-destructive integrity testing method which makes use of the hydration heat from the concrete curing process to detect defects within a drilled shaft. Any defect of concrete could result in a temperature anomaly in a drilled shaft. The accuracy of the current …


Strengthening Of Concrete Deep Beams With Extreme Discontinuities Using Near-Surface Mounted Composites, Moustafa Seifeddin Mansour Nov 2019

Strengthening Of Concrete Deep Beams With Extreme Discontinuities Using Near-Surface Mounted Composites, Moustafa Seifeddin Mansour

Civil and Environmental Theses

Installation of a web opening that fully interrupts the natural load path in concrete deep beams produces regions of extreme discontinuities and reduces the shear strength. This research examined the effectiveness of using near-surface-mounted carbon fiber-reinforced polymer (NSM-CFRP) reinforcement to restore the shear strength of deep beams with extreme discontinuities. The strut-and-tie model (STM) procedures were utilized to develop three different strengthening solutions around the discontinuity regions. A total of eight deep beam specimens (150 x 500 x2700 mm) with a shear span-to-depth ratio of a/h = 0.8 were constructed and tested. One beam was solid. Seven beams had a …


Modeling And Simulation Of Damage In The Brazilian Indirect Tension Test Using The Finite-Discrete Element Method, Jeremiah C. Leyba Aug 2018

Modeling And Simulation Of Damage In The Brazilian Indirect Tension Test Using The Finite-Discrete Element Method, Jeremiah C. Leyba

Civil Engineering ETDs

The Brazilian indirect tension test is used to investigate possible correlations between progressive damage and associated permeability changes. The test offers ease of replicability with a damage behavior known to lead to fracture openings as a tool for interpreting the indirect tensile strength of concrete and rocks. This behavior can lend insight into the nature of tensile damage and fracture progression in association with changes in permeability. The nature of these brittle materials is known to exhibit rapid failures in the Brazilian indirect tension test and require a method to retard the progression of damage for the possibility of acquiring …


Meso-Scale Simulation Of Size-Dependent Shear Behavior In Glass Fiber Reinforced Polymer Reinforced Concrete Beams Without Stirrups, Sina Khodaie Jan 2018

Meso-Scale Simulation Of Size-Dependent Shear Behavior In Glass Fiber Reinforced Polymer Reinforced Concrete Beams Without Stirrups, Sina Khodaie

Theses and Dissertations

There is extensive experimental evidence of the decrease in the shear stress at failure at increasing effective depths in concrete beams reinforced with glass fiberreinforced polymer (GFRP) bars without shear reinforcement. An important practical implication is that extrapolating strength values from typical laboratory-scaled experiments to design larger members may be misleading. The complexity of the underlying mechanics is reflected in the difficulty of using commercially available numerical tools to accurately estimate shear strength irrespective of beam size. This dissertation presents research on a Lattice Discrete Particle Model (LDPM) based model to simulate the response of scaled slender GFRP reinforced concrete …


Experimental And Numerical Evaluation Of A New Composite Pressure Pipe For A Trenchless Rehabilitation Technology, Xuanchen Yen Jul 2016

Experimental And Numerical Evaluation Of A New Composite Pressure Pipe For A Trenchless Rehabilitation Technology, Xuanchen Yen

Doctoral Dissertations

The information presented in this dissertation is based on research work conducted at Trenchless Technology Center (TTC) at Louisiana Tech University. This work was performed through a contract with China University of Geoscience (CUG) for a gas company. China's gas pipelines need replacement or rehabilitation after 15 to 30 years of service. China's gas industry is looking for suitable techniques to transfer into their market.

When compared to conventional excavation pipeline renewal or replacement methods, there are obvious advantages of TRT for gas pipelines that can impact the triple bottom-line of economic, social and environmental benefits. An introduction of TRT …


3d Infrastructure Condition Assessment For Rail Highway Applications, Teng Wang Jan 2016

3d Infrastructure Condition Assessment For Rail Highway Applications, Teng Wang

Theses and Dissertations--Civil Engineering

Highway roughness is a concern for both the motoring public and highway authorities. Roughness may even increase the risk of crashes. Rail-highway grade crossings are particularly problematic. Roughness may be due to deterioration or simply due to the way the crossing was built to accommodate grade change, local utilities, or rail elevation. With over 216,000 crossings in the US, maintenance is a vast undertaking. While methods are available to quantify highway roughness, no method exists to quantitatively assess the condition of rail crossings. Conventional inspection relies on a labor-intensive process of qualitative judgment. A quantifiable, objective and extensible procedure for …


A Robust Data Exchange Framework For Connected Vehicle Technology Supported Dynamic Transit Operations, Yucheng An Dec 2015

A Robust Data Exchange Framework For Connected Vehicle Technology Supported Dynamic Transit Operations, Yucheng An

All Theses

Transit systems are an integral part of surface transportation systems. A connected vehicle technology (CVT) supported transit system will assist the users to manage trips both dynamically and efficiently. The primary focus of this research is to develop and evaluate the performance of a secure, scalable, and resilient data exchange framework. In the developed data exchange framework, a new data analytics layer, named Transit Cloud, is used to receive data from different sources, and send it to different users for a Dynamic Transit Operations (DTO) application. The DTO application allows the transit users to request trip information and obtain itineraries, …


Tropical Cyclone Wind Hazard Assessment For Southeast Part Of Coastal Region Of China, Sihan Li Aug 2015

Tropical Cyclone Wind Hazard Assessment For Southeast Part Of Coastal Region Of China, Sihan Li

Electronic Thesis and Dissertation Repository

Tropical cyclone (TC) or typhoon wind hazard and risk are significant for China. The return period value of the maximum typhoon wind speed is used to characterize the typhoon wind hazard and assign wind load in building design code. Since the historical surface observations of typhoon wind speed are often scarce and of short period, the typhoon wind hazard assessment is often carried out using the wind field model and TC track model. For a few major cities in the coastal region of mainland China, simple or approximated wind field models and a circular subregion method (CSM) have been used …


Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara Mar 2015

Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara

Theses and Dissertations

The goal of this study is to use Modeling and Simulation of Evacuation Plan (MSEP) to support management to execute proper evacuation plan in case of emergency at Hancock Stadium in Illinois State University. Analyses of the research literature and evacuation scenarios are used to build a simulation system that will connect a description of emergency and evacuation situation with its context. It shows how an evacuation plan actually functions. The results of the study will help safety managers to understand the current situations of evacuation according to the specific simulation scenarios. The evacuation simulation is categorized according to the …


A New Methodology For Evaluating The Effectiveness Of Bus Rapid Transit Strategies, Ahmad Alomari Jan 2015

A New Methodology For Evaluating The Effectiveness Of Bus Rapid Transit Strategies, Ahmad Alomari

Electronic Theses and Dissertations

Over the last few years, public transportation has become more desirable as capacity of existing roadways failed to keep up with rapidly increasing traffic demand. Buses are one of the most common modes of public transportation with low impact on network capacity, especially in small and congested urban areas. However, the use of regularly scheduled buses as the main public transport mode can become useless with the presence of traffic congestion and dense construction areas. In cases like these, innovative solutions, such as bus rapid transit (BRT), can provide an increased level of service without having to resort to other, …


Data-Driven Simulation Modeling Of Construction And Infrastructure Operations Using Process Knowledge Discovery, Reza Akhavian Jan 2015

Data-Driven Simulation Modeling Of Construction And Infrastructure Operations Using Process Knowledge Discovery, Reza Akhavian

Electronic Theses and Dissertations

Within the architecture, engineering, and construction (AEC) domain, simulation modeling is mainly used to facilitate decision-making by enabling the assessment of different operational plans and resource arrangements, that are otherwise difficult (if not impossible), expensive, or time consuming to be evaluated in real world settings. The accuracy of such models directly affects their reliability to serve as a basis for important decisions such as project completion time estimation and resource allocation. Compared to other industries, this is particularly important in construction and infrastructure projects due to the high resource costs and the societal impacts of these projects. Discrete event simulation …


Developing A Framework For Determining The Contribution Of Transportation Project To Sustainable Development, Karim Ahmed Abdel Warith Oct 2013

Developing A Framework For Determining The Contribution Of Transportation Project To Sustainable Development, Karim Ahmed Abdel Warith

Open Access Dissertations

In the past few years, stakeholders in the transportation industry have been concerned with sustainability. However, transportation decision makers have had difficulty incorporating sustainability into transportation infrastructure decisions. This is mainly attributed to the vagueness of the term. Incorporating sustainability into transportation decision making has been a desire put forth by engineers for that past 10 years. However, with no apparent method of defining sustainability, designers and decision makers have not been able to fulfill this desire.

This investigation attempts to define sustainability in a comprehensive and quantitative manner. The research proposes a new methodology that relies on the objective …


A Study On Lane-Change Recognition Using Support Vector Machine, Weiping Deng Jan 2013

A Study On Lane-Change Recognition Using Support Vector Machine, Weiping Deng

USF Tampa Graduate Theses and Dissertations

This research focuses primary on recognition of lane-change behaviors using support vector machines (SVMs). Previous research and statistical results show that the vast majority of motor vehicle accidents are caused by driver behavior and errors. Therefore, the interpretation and evaluation of driver behavior is important for road safety analysis and improvement. The main limit to understanding driver behavior is the data availability. In particular, a full-scale lane-change data set is difficult to collect in a real traffic environment because of the safety and cost issues. Considering the data demands of the recognition model development and the obstacles of field data …


A Framework For Process Data Collection, Analysis, And Visualization In Construction Projects, Reza Akhavian Jan 2012

A Framework For Process Data Collection, Analysis, And Visualization In Construction Projects, Reza Akhavian

Electronic Theses and Dissertations

Automated data collection, simulation and visualization can substantially enhance the process of designing, analysis, planning, and control of many engineering processes. In particular, managing processes that are dynamic in nature can significantly benefit from such techniques. Construction projects are good examples of such processes where a variety of equipment and resources constantly interact inside an evolving environment. Management of such settings requires a platform capable of providing decision-makers with updated information about the status of project entities and assisting site personnel making critical decisions under uncertainty. To this end, the current practice of using historical data or expert judgments as …


Analysis Of Passive Louver Shading Systems And Impact On Interior Environment, Cory Joseph Brennan Jan 2012

Analysis Of Passive Louver Shading Systems And Impact On Interior Environment, Cory Joseph Brennan

Masters Theses

An installed passive louver shading systems can affect the heating, cooling, and lighting loads of any building, by altering the amount of solar energy, in the form of light and heat, from entering. The benefits of a louver system are derived from the application of solar geometry incident on the site and the climate within the area. By optimizing a passive louver system's design parameters, a building can reduce the total annual energy consumption due to artificial heating, cooling loads and artificial lighting. This research has implemented simulation modeling software, Energy Plus, to predict the effect of passive louver shades …


Methodology To Convert A Transportation Planning Origin-Destination Matrix Into A Microscopic Traffic Simulation Origin-Destination Matrix, Jose Osiris Vidana-Bencomo Jan 2011

Methodology To Convert A Transportation Planning Origin-Destination Matrix Into A Microscopic Traffic Simulation Origin-Destination Matrix, Jose Osiris Vidana-Bencomo

Open Access Theses & Dissertations

Microscopic traffic simulation (MTS) is a cost-effective approach for the evaluation of traffic conditions in urban highways networks. In MTS models, traffic demand that is entered into the network is specified by one or several Origin-Destination (O-D) matrices. A major challenge in the application of MTS for large urban networks is the specification of the O-D matrices. This dissertation proposes a methodology that may be used to transform a O-D matrix from a transportation planning model (which is based on Traffic Analysis Zone, or TAZ, and is readily available) into a O-D matrix for a MTS model (which is traffic …


Operational Performance Evaluation Of Four Types Of Exit Ramps On Florida's Freeways, Linjun Lu Jan 2011

Operational Performance Evaluation Of Four Types Of Exit Ramps On Florida's Freeways, Linjun Lu

USF Tampa Graduate Theses and Dissertations

This research focuses primarily on the analysis of exit ramp performance related to safety and operations. The safety analysis focuses on the impacts of different exit ramp types for freeway diverge areas and different factors contributing to the crashes that occur on the exit ramp sections. The operational analysis is based mainly on simulations by TSIS-CORSIM. Different ramp effects and guidance for selecting optimal exit ramp type are concluded. Issues related to ramp sections and crossroad sections are also demonstrated. Minimum ramp length and minimum distance between ramp terminal and downstream or upstream intersections are calculated. The operational analysis was …


Reliability-Based Underseepage Analysis In Levees Using Monte Carlo Simulation, Lourdes Polanco May 2010

Reliability-Based Underseepage Analysis In Levees Using Monte Carlo Simulation, Lourdes Polanco

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A new method for assessing the potential for unsatisfactory levee performance due to underseepage is presented. Specifically, the method assesses the potential for the initiation of piping (the internal backward erosion of the foundation or embankment caused by seepage). Current assessment methods consist of deterministic seepage analyses and simplified reliability methods. Deterministic methods produce either a maximum hydraulic exit gradient or a Factor of Safety against piping but they do not account for high levels of uncertainty in soil properties and subsurface geometry that are inherent to many levee analyses. The most common simplified reliability approaches that are currently being …


Safety And Operational Evaluation Of Dynamic Lane Merging In Work Zones, Rami Harb Jan 2009

Safety And Operational Evaluation Of Dynamic Lane Merging In Work Zones, Rami Harb

Electronic Theses and Dissertations

Traffic safety and mobility of roadway work zones have been considered to be one of the major concerns in highway traffic safety and operations in Florida. In intent to expose Florida's work zones crash characteristics, the Florida Traffic Crash Records Database for years 2002, 2003 and 2004 were explored. Statistical models were estimated and Florida's work zone crash traits for single vehicle crashes and two-vehicle crashes were drawn. For the single-vehicle crashes, trucks were found more likely to be involved in single vehicle crashes in freeway work zones compared to freeways without work zones. Straight level roadways are significantly affected …


The Calibration, Validation, And Comparison Of Vissim Simulations Using The Two-Fluid Model, Jeremy Crowe Jan 2009

The Calibration, Validation, And Comparison Of Vissim Simulations Using The Two-Fluid Model, Jeremy Crowe

Electronic Theses and Dissertations

The microscopic traffic simulation program VISSIM is a powerful tool that has been used by transportation engineers and urban planners around the world. A VISSIM simulation is meant to depict the performance of the physical road network through the use of modeling tools and behavioral parameters. The process which gets the model to the point of matching real world conditions is called calibration and requires a means of relating the real world to the simulated world. The topic of this thesis discusses a new means of calibration using the two-fluid model. The two-fluid model is a macroscopic modeling technique which …


A Real-Time Traffic Condition Assessment And Prediction Framework Using Vehicle-Infrastructure Integration (Vii) With Computational Intelligence, Yongchang Ma Aug 2008

A Real-Time Traffic Condition Assessment And Prediction Framework Using Vehicle-Infrastructure Integration (Vii) With Computational Intelligence, Yongchang Ma

All Dissertations

This research developed a real-time traffic condition assessment and prediction framework using Vehicle-Infrastructure Integration (VII) with computational intelligence to improve the existing traffic surveillance system. Due to the prohibited expenses and complexity involved for the field experiment of such a system, this study adopted state-of-the-art simulation tools as an efficient alternative.
This work developed an integrated traffic and communication simulation platform to facilitate the design and evaluation of a wide range of online traffic surveillance and management system in both traffic and communication domain. Using the integrated simulator, the author evaluated the performance of different combination of communication medium and …


Steer It And Clear It: Effectiveness Of Quick Clearance Legislation, Amy Carol Hamlin Aug 2007

Steer It And Clear It: Effectiveness Of Quick Clearance Legislation, Amy Carol Hamlin

All Theses

Innovative incident management strategies have been sought by transportation professionals to minimize the impacts of incidents on traffic operation and safety. Some current quick clearance strategies such as 'Steer It and Clear It' legislation in South Carolina, which requires driver(s) of involved vehicle(s) in a minor incident to move vehicles promptly from the traveled roadway prior to the arrival of the first responders, can potentially reduce the duration of an incident. The research detailed in this paper endeavored to measure the benefit of the Steer It and Clear It law on a section of I-85 in South Carolina. A simulation …