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Articles 1 - 30 of 37
Full-Text Articles in Engineering
Methane Oxidation Potential Of Uncomposted Yard Waste As A Landfill Biocover, Gomathy Radhakrishna Iyer
Methane Oxidation Potential Of Uncomposted Yard Waste As A Landfill Biocover, Gomathy Radhakrishna Iyer
Civil Engineering Dissertations
Biocovers are widely used in landfills to oxidize emissions of the greenhouse gas methane. Biocovers used till date are fully or partially made of composts. Compost takes time and effort to create, and costs about $10 per cubic yard on an average. Even more importantly, however, production of compost, although theoretically an aerobic process, actually generates methane, from 3.2 to 362 kg CO2-equivalents per ton of wet waste composted, depending on the type of waste, whether open or enclosed composting technology is used, and other factors. To reduce the net greenhouse gas emissions from biocovers, this research explores the potential …
Structural Safety Of Bridge Decks With Variable Rebar Cover, Prem Egade
Structural Safety Of Bridge Decks With Variable Rebar Cover, Prem Egade
Civil Engineering Theses
Construction defects are common and are difficult to avoid completely. This arises due to improper workmanship, inspection, drawing and specification. On bridge decks, achieving the desired cover is necessary since inadequacy can cause accelerated corrosion in steel and for the most part spalling and delamination which ultimately led to failure. Tolerance provided by different standards and specification also restrict the amount of rebar. So, construction is more focused on increasing cover undermining the loss of strength as consequence. The objective of this research is to check the safety of decks by analyzing bridges for reduction in capacity due to cover …
Development Of The Urban Passenger Transportation Life Cycle Inventory For Comparison Across Modes Model (Transportlifecamm), Alma Angelica Hernandez Ruiz
Development Of The Urban Passenger Transportation Life Cycle Inventory For Comparison Across Modes Model (Transportlifecamm), Alma Angelica Hernandez Ruiz
Civil Engineering Dissertations
Against the backdrop of the increasingly complex urban passenger transportation challenges associated with megacities during the 21st century, and the effort to find the most sustainable modes of transportation for them, the spreadsheet-based model TransportLifeCAMM was developed. This model allows users in the US and Mexico to compare life cycle environmental impacts from automobile, bus, and/or subway. While other models to estimate environmental burdens from transportation exist, few of them consider emissions or energy consumption over the entire life cycle of the vehicle and the fuel (including vehicle manufacture, fuel production, maintenance, and end-of-life disposal). Furthermore, even fewer of the …
Novel Infrastructure Monitoring Using Multifaceted Unmanned Aerial Vehicle Systems - Close Range Photogrammetry (Uav - Crp) Data Analysis, Surya Sarat Chandra Congress
Novel Infrastructure Monitoring Using Multifaceted Unmanned Aerial Vehicle Systems - Close Range Photogrammetry (Uav - Crp) Data Analysis, Surya Sarat Chandra Congress
Civil Engineering Dissertations
Remote sensing is a method of collecting data without making any physical contact with the object under inspection. Modern day remote sensing kicked off with the invention of the camera and continued on to the invention of advanced satellite mounted sensors. Photogrammetry is defined as a science that measures distances using one or more images captured remotely. Remote collection of images within a range of 1000 ft is termed close-range photogrammetry (CRP). Unmanned aerial vehicle systems (UAV or UAS) have become a popular means of remotely gathering information and assessing infrastructure conditions due to their versatile nature. Multirotor and fixed-wing …
Hpfrc And Rc Slab-Beam-Column Connections Under Extreme Earthquake Loading And Further Improvement Of Novel Double-Beam-Coupling Beams, Youngjae Choi
Hpfrc And Rc Slab-Beam-Column Connections Under Extreme Earthquake Loading And Further Improvement Of Novel Double-Beam-Coupling Beams, Youngjae Choi
Civil Engineering Dissertations
The work presented in this dissertation is divided into two parts. Each part has drawn its own results. Reinforced concrete (RC) buildings resist a strong earthquake through structural foundations, diaphragms, and vertical elements. Moment-resisting frames and shear walls are primary-used vertical elements in RC buildings. The moment-resisting frames consist of columns, beams that frame into the column and beam column joints where the columns and beams meet. A key point of designing the moment-resisting frames against a strong earthquake is to ensure beam-column connections to dissipate as much energy possible. The shear wall often becomes two separate slender cantilever walls …
Field Swcc Modeling And Soil Water Storage Evaluation Through Geophysical Testing, Linkan Sarker
Field Swcc Modeling And Soil Water Storage Evaluation Through Geophysical Testing, Linkan Sarker
Civil Engineering Theses
Evapotranspiration (ET) landfill cover is an emerging final cover system and offers several benefits over conventional landfill closure system. It is a cost-effective green solution for the sustainability of a landfill as its performance enhances with time compared to the conventional solution where low hydraulic conductivity soil barrier deteriorates with time. ET cover system relies on the water store-release principle and its performance depends on the site-specific factors such as on-site climatological conditions, soil hydraulic properties and native vegetation. To effectively monitor the performance of this type of cover system, its unsaturated behavior, field capacity, available moisture for plant growth, …
Utilization Of Geocell-Reinforced Rap Material Base Layer In Flexible Pavements: Experimental And Numerical Studies, Anu Muthumala George
Utilization Of Geocell-Reinforced Rap Material Base Layer In Flexible Pavements: Experimental And Numerical Studies, Anu Muthumala George
Civil Engineering Dissertations
Reclaimed asphalt pavement (RAP) materials have been considered as one of the most sustainable and cost-effective options in the pavement industry. The use of RAP materials in pavement construction reduces natural resources depletion and the volume of construction debris discarded into the landfills. However, the low shear strength and high permanent deformation (PD) of RAP materials often limit their application in road bases. Utilization of mechanical stabilizers, such as geocell, for stabilizing RAP bases, have found to be effective in improving the pavement performance. The main objective of this study is to assess the efficacy of high-density polyethylene (HDPE) geocell …
Post-Disaster Construction Labor Cost Fluctuations: Measurement And Modeling, Navid Ahmadi Esfahani
Post-Disaster Construction Labor Cost Fluctuations: Measurement And Modeling, Navid Ahmadi Esfahani
Civil Engineering Dissertations
The United States has been one of the top five countries most frequently hit by natural disasters. The post-disaster survival of cities and communities depend on their capabilities to reconstruct and repair damages to buildings and other infrastructure systems. The significant increase in the repair costs following large-scale natural disasters, also called “demand surge,” slows down the repair process that impacts many lives touched by large-scale natural disasters. Previous studies showed that post-disaster construction labor cost escalation drives the total post-disaster construction cost escalation in the U.S. The ultimate goal of this research is to (1) measure post-disaster construction labor …
Laboratory And Field Study Of A Liquid Ionic Soil Stabilizer, Sandesh Gautam
Laboratory And Field Study Of A Liquid Ionic Soil Stabilizer, Sandesh Gautam
Civil Engineering Theses
Chemical stabilization of expansive soil has been practiced for quite a time now. The use of lime/cement stabilization as a traditional method has been well acknowledged, understood and standard guidelines for practice have been developed. However, owing to certain demerits like high production and application cost, environmental impact, durability issues and most importantly incompatibility with high-sulfate soil leading to excessive heaving and swell, there is need to develop alternatives to these stabilizers. Non-traditional stabilizers like ionic soil stabilizer have been used by manufacturers in the past and claimed to effectively reduce the swell-shrink behavior of expansive soil. Undocumented results, the …
Experimental And Numerical Investigation Of The Concrete Shear Strength Of Reinforced Concrete Box Culverts Under Uniformly Distributed Load, Masoud Ghahremannejad
Experimental And Numerical Investigation Of The Concrete Shear Strength Of Reinforced Concrete Box Culverts Under Uniformly Distributed Load, Masoud Ghahremannejad
Civil Engineering Dissertations
This research resulted in the development of a new method for performing displacement control analysis of distributed loads to obtain the ultimate shear strength of structural components. A framework, consisting of several sub-frames, was designed to convert the single displacement applied at the top of the framework to equivalent uniformly-distributed forces applied to the beam. To validate the loading mechanism, using the proposed framework, the load was applied on the top of a reinforced concrete beam in the laboratory, and numerical studies were conducted. The shear capacity of the beam under a concentrated load at mid-span was compared with the …
Algorithm Development For Sewer Pipe System Condition Assessment Using Multi-Sensor (Msi) Technology, Mohammed Al Asadi
Algorithm Development For Sewer Pipe System Condition Assessment Using Multi-Sensor (Msi) Technology, Mohammed Al Asadi
Civil Engineering Dissertations
This study investigates the performance of all the current large-diameter pipeline system of The City of Arlington (COA) sewer lines of 48 miles (24-inch inner diameter and above for rigid and flexible pipes). Proper inspection and rehabilitation plan for the city sewer pipeline system are better choice for the municipality and tax payers in terms of cost than dealing with pipe damage and collapsing problems when they happen. The City of Arlington (COA), University of Texas at Arlington (UTA) and RedZone Robotics have established a Technology Partnership Program (TPP) to perform a condition assessment on the all COA large diameter …
Developing A Framework To Optimize The Operations Of An Intermodal Underground Freight Transportation Terminal Using Simulation, Fatemeh Rezaeifar
Developing A Framework To Optimize The Operations Of An Intermodal Underground Freight Transportation Terminal Using Simulation, Fatemeh Rezaeifar
Civil Engineering Dissertations
According to the U.S. Department of Transportation (USDOT), by 2040, nearly 30,000 miles of our busiest highways will be clogged daily and it is important to increase the capacity of our transportation system. Construction of intermodal underground freight transportation (UFT) systems for freight movement through underground pipelines or tunnels, can increase the capacity of the existing shipping network. The intermodal terminal is a major component of the UFT’s innovative infrastructure project. Increasing demand for container transportation systems in terminals will raise the risk of terminal congestion and delivery delay due to the increase in freight transportation system bottlenecks (traffic jams …
Evaluation And Strengthening Of Elevated Slab On Grade With Fiber-Reinforced Polymer (Frp) Laminates, Natawut Chaiwino
Evaluation And Strengthening Of Elevated Slab On Grade With Fiber-Reinforced Polymer (Frp) Laminates, Natawut Chaiwino
Civil Engineering Dissertations
Elevating a residential house appears to be one of the most effective techniques to eliminate or alleviate flood losses. In general, the elevation procedures involve raising a house as well as its typical slab-on-grade (SOG) foundation and supporting it with an additional support system. The unconcerned effects of the drastic changes in support condition could lead to severe structural damages and failure of houses. After elevated, thus, such slabs must be properly supported and retrofitted, for which the available methodology and know-how is almost nonexistent. The fiber reinforced polymer (FRP) application, considered as a promising technique in the rehabilitation of …
A New Approach For Performance Evaluation Of Bridge Infrastructure Using Terrestrial Lidar And Advanced Mathematical Modeling, Ali Shafikhani
A New Approach For Performance Evaluation Of Bridge Infrastructure Using Terrestrial Lidar And Advanced Mathematical Modeling, Ali Shafikhani
Civil Engineering Dissertations
High plastic expansive clays when subjected to different climatic conditions undergo large ground movements causing distress to infrastructures including bridges, pavements, buildings, retaining structures, and others. Performance assessment of these structures built on problematic soils such as expansive clays is important to reduce maintenance and extending the design life of infrastructure. Rapid developments in remote sensing technologies with precise evaluation have influenced the monitoring techniques for assessing the health condition of civil infrastructure projects. While these technologies have considerably aided in performance evaluation, cogent procedures for evaluating the ground movements are still required that integrates technologies, climatic factors, soil behavior …
Development Of A Framework To Estimate Social And Environmental Costs Of Truck, Railroad, And Underground Freight Transportation, Amir Tabesh
Civil Engineering Dissertations
Increasing freight transportation capacity is the most important factor to keep US economy viable. Trucks moved 11.5 billion tons of goods, or 63.8 percent of total freight shipments in 2015, which is projected to grow to 16.6 billion tons by 2045. It is predicted truck travel may increase from 282 million miles per day in 2012 to 488 million miles per day by 2045. The U.S. railroad system includes 138,000 rail miles, which 93,500 miles owned and operated by Class I railroad and the rest of them owned and operated by regional and local railroads. While the miles of railroad …
Evaluation Of Fiber Reinforced Polymer (Frp) Strengthening For Deteriorated Bridge Bent Caps, Yazan Almomani
Evaluation Of Fiber Reinforced Polymer (Frp) Strengthening For Deteriorated Bridge Bent Caps, Yazan Almomani
Civil Engineering Dissertations
Deterioration of aging highway bridges has been a serious concern in the U. S. A. Almost 39% percent of all bridges in the country have passed their 50-year design life, and approximately 9% of these bridges are structurally deficient due to concrete deterioration and truck weight increases on highways. Compared to superstructures, the deterioration of bridge substructures and associated repair/strengthening/evaluation has received much less attention in previous studies. A reinforced concrete bridge built in 1940 and located in Dallas, Texas, exhibited moderate to severe corrosion related concrete deterioration in the bent caps. Eight such bent caps were selected herein for …
Planning, Design, And Operational Analysis Of Underground Freight Transportation Systems With Individual Autonomous Vehicles, Sirwan Shahooei
Planning, Design, And Operational Analysis Of Underground Freight Transportation Systems With Individual Autonomous Vehicles, Sirwan Shahooei
Civil Engineering Dissertations
Given the increases in freight transportation demand, the current infrastructure for freight transportation appears insufficient. Moreover, the future development of capacity for freight transportation infrastructure seems to be limited. Based on a U.S. DOT report, most of the U.S. freight transportation infrastructure’s construction dates back to the 1960s. This puts a heavy burden on the national highway and railroad systems. The growing demand for freight will increase truck traffic on both urban and rural highways. The increase in truck traffic on highways will result in multiple challenges, including traffic congestion, security concerns, infrastructure deterioration, environmental pollution, energy consumption, increase in …
In-Service Performance Evaluation Of Fire And Impact Damaged Bridges With Cfrp Laminate Strengthening, Santosh Timilsina
In-Service Performance Evaluation Of Fire And Impact Damaged Bridges With Cfrp Laminate Strengthening, Santosh Timilsina
Civil Engineering Dissertations
Fire events and impact damage on bridges are few of the least understood of common extreme events. Bridge infrastructures that are subjected to hazards such as fire or impact from over height vehicle can catastrophically collapse or be heavily damaged. External wrapping of damaged concrete bridge components with Fiber Reinforced Polymer (FRP) laminates has been used as a strengthening technique for these bridges. Two such in-service bridges, one of which was fire damaged and the other impact damaged, both aged more than 50 years old in Irving, Texas, were selected for this study. The damaged beams of the concrete bridges …
A Comprehensive Seismic Response And Slope Stability Analysis Framework For Evaluating The Stability Of Hydraulic-Fill Dams, Sayantan Chakraborty
A Comprehensive Seismic Response And Slope Stability Analysis Framework For Evaluating The Stability Of Hydraulic-Fill Dams, Sayantan Chakraborty
Civil Engineering Dissertations
The stability and serviceability of earthen embankment structures such as dams and levees are extremely crucial to avoid the catastrophic consequences of the failure of these structures. Such man-made geo-structures are usually stable under normal working conditions; however, the stability and subsequent functionality may be affected during earthquake events. Hence, the evaluation of seismic response and structural stability of earthen dams is an important facet in the field of geotechnical earthquake engineering. Dams and levees built in earthquake-prone regions are usually designed to withstand expected seismic events, and in-depth time-history-based dynamic analyses are typically performed to assess the behavior of …
A Calibration Chamber For Thermo-Hydro-Mechanical Studies Of Soil Behavior Via Resonant Column Testing, Daniel R. C. Green
A Calibration Chamber For Thermo-Hydro-Mechanical Studies Of Soil Behavior Via Resonant Column Testing, Daniel R. C. Green
Civil Engineering Theses
Abstract A Calibration Chamber for Thermo-hydro-mechanical Studies of Soil Behavior via Resonant Column Testing Daniel R. C. Green The University of Texas at Arlington, 2018 Supervising Professor: Dr. Laureano Hoyos A considerable portion of the emerging geothermal infrastructure in the country is located in earthquake prone areas while being supported and/or surrounded by soil deposits located well above the groundwater table. Geotechnical earthquake research in the country, however, continues to be mostly focused on soil response under saturated conditions, especially soil liquefaction phenomena, while most of the work on dynamic response of compacted soils has not taken suction or thermal …
An Investigation Of Water Pipeline Renewal Practices, Abbas Abed Salman
An Investigation Of Water Pipeline Renewal Practices, Abbas Abed Salman
Civil Engineering Theses
Globally, the use of trenchless technologies is gradually increasing due to the growing need to replace and renew aging utility infrastructure and the need for more flexible solutions for the installation of new pipes. In the United States of America, the American Society of Civil Engineers (ASCE) in 2017 assessed that America’s infrastructure is close to failing. It faces an annual shortfall of at least $11 billion to replace the aging facilities that are near the end of their useful lives. In this research, surveys and interviews of professionals working in trenchless technologies for the North American Society for Trenchless …
Diagnosis And Quantification Of Post-Disaster Construction Material Cost Fluctuations, Niloufar Khodahemmati
Diagnosis And Quantification Of Post-Disaster Construction Material Cost Fluctuations, Niloufar Khodahemmati
Civil Engineering Theses
The post-disaster survival of cities and communities depend on their capabilities to rapidly reconstruct damages. Temporary increase in construction costs following natural disasters, also known as “demand surge,” impedes the rapid post-disaster reconstruction process. The existing methods for quantifying the post-disaster construction cost escalations do not consider seasonal patterns and inflation of costs under normal condition. Therefore, it is not clear whether the quantified construction cost increases are due to a disaster or merely associated with seasonal patterns and inflation. The objective of this study is to (1) create an approach to statistically quantify the post-disaster construction material cost fluctuations …
Remaining Useful Life Prediction Of Water Pipes Using Artificial Neural Network And Adaptive Neuro Fuzzy Inference System Models, Razieh Tavakoli
Remaining Useful Life Prediction Of Water Pipes Using Artificial Neural Network And Adaptive Neuro Fuzzy Inference System Models, Razieh Tavakoli
Civil Engineering Dissertations
The U.S. water distribution system contains thousands of miles of pipes with differing materials, sizes, and ages. These pipes experience physical, environmental, structural and operational parameters that cause corrosion and eventually lead to their failures. The Remaining Useful Life (RUL) is the estimated time before a pipe will experience a failure mode specifically a pipe break. Pipe failure means collapse and deterioration of water pipes overtime. Pipe deterioration results in increased break rates, reduced hydraulic capacity, and detrimental impacts on water quality. Therefore, it is crucial to perform accurate models that can forecast deterioration rates along with estimates of remaining …
Framework For Determining The Pullout Resistance Of Inextensible 2-Wire Soil-Reinforcing Elements Embedded In Sand, Thomas Patrick Taylor
Framework For Determining The Pullout Resistance Of Inextensible 2-Wire Soil-Reinforcing Elements Embedded In Sand, Thomas Patrick Taylor
Civil Engineering Dissertations
Mechanically Stabilized Earth (MSE) has been successfully used as a commercial retaining structure since its development in 1963 by Henry Vidal (Schlosser 1990). MSE is a ground improvement system that consists of soil-reinforcing, compacted backfill, and a facing. The initial soil-reinforcing developed for commercial use by Vidal consisted of a smooth steel strip. Since then, a diverse range of soil-reinforcing has been developed, including extensible and inextensible reinforcing. The various geometric configurations of soil-reinforcing have included wide width and narrow width elements comprising planar strips, planar grids, co-planar strips, co-planar grids, and wide sheets. General specifications categorize inextensible soil-reinforcing into …
Impacts Of Geotechnical Aspects In Tunneling Design And Construction, Mohammad Haadi Sadaghiani
Impacts Of Geotechnical Aspects In Tunneling Design And Construction, Mohammad Haadi Sadaghiani
Civil Engineering Theses
In tunneling project, different type of methods is conducted to do the project. Knowing geotechnical aspects of tunnel project is unavoidable and crucial in early stage of project especially before contract to have efficient and more accurate design and prevent cost overruns, reduce bid price and reduce project risks. However, all that geotechnical information should be based on standard guidelines such as Geotechnical Baseline Report (GBR) to help owner how to provide those geotechnical data in bid contract and use it as a guideline in contract to prevent future claim or disputes. The main objective of this thesis is about …
Assessment Of Sustainability And Resilience In Transportation Infrastructure Geotechnics, Jasaswee T. Das
Assessment Of Sustainability And Resilience In Transportation Infrastructure Geotechnics, Jasaswee T. Das
Civil Engineering Dissertations
Transportation infrastructure, such as roads, embankments, bridges, railroads, airports, docks, and canals, serve as pathways for the mobility of people, goods, and services, and form the backbone of cities and communities. The construction, operation, and rehabilitation of these facilities put significant strain on the local, state, and federal agencies, including depletion of natural resources, and contributing to the global carbon footprint and greenhouse gas emissions. Further, these features stimulate anthropocentric development in a region which affects the land-use patterns and influences the demography of communities. In recent years, most transportation infrastructure are typically designed to withstand external and internal disturbances …
Effect Of Fine Grained Soil In The Strength Of Cement Treated Flex-Base Materials, Sita Timsina
Effect Of Fine Grained Soil In The Strength Of Cement Treated Flex-Base Materials, Sita Timsina
Civil Engineering Theses
The recycled materials such as, Recycled Crushed Concrete Aggregates (RCCA) and Reclaimed Asphalt Pavement (RAP) treated with cement has been widely used as the alternative granular base in pavement construction in different states in USA due to the depletion of natural resources of virgin aggregates. While a number of factors drive the use of these recycled materials, the two primary factors are economic savings and environmental benefits. In the flexible pavement systems, the base layer contributes to the structural capacity of the pavement systems, so, the quality performance of this layer is essential. However, presence of fine particles in the …
Environmental Life Cycle Assessment Of Commercial Space Transportation Activities In The United States, Shelia Scott Neumann
Environmental Life Cycle Assessment Of Commercial Space Transportation Activities In The United States, Shelia Scott Neumann
Civil Engineering Dissertations
The Commercial Space Transportation (CST) activities in the United States are increasing and have increased over 50% in the last year. The launches in the United States for commercial purposes are expected to increase another 50% in the next 3-5 years. National Environmental Policy Act (NEPA) environmental assessments do provide the regulatory environmental analysis for launching space vehicles within the United States. However, the environmental impacts from these launches have not been fully characterized. One method to characterize environmental impacts from a system is through conducting a Life Cycle Assessment (LCA) based on an international standard, ISO14040. The results from …
Identification Of Phase-Based Key Performance Factors And Their Best Practices In Construction Projects, Mohammadreza Habibi
Identification Of Phase-Based Key Performance Factors And Their Best Practices In Construction Projects, Mohammadreza Habibi
Civil Engineering Theses
Delay and cost overrun in construction projects are two widespread problems arousing practitioners’ and scholars’ concerns as poor time and cost performance lead construction projects to failure. It is estimated that more than half of the construction industry’s projects encounter significant cost overruns and major delays, resulting in the industry having a tarnished reputation. Despite the attempts of numerous researchers to identify key performance factors, their results have been inconsistent. Most of the literature has focused solely on the construction phase budget and time overruns; the engineering/design and procurement phase costs and schedule performances have been rarely studied. Therefore, the …
Determination Of Root Length Of Evapotranspiration Cover Using Electrical Resistivity Imaging Technique, Fouzia Hossain Oyshi
Determination Of Root Length Of Evapotranspiration Cover Using Electrical Resistivity Imaging Technique, Fouzia Hossain Oyshi
Civil Engineering Theses
Evapotranspiration (ET) covers are receiving an increasing amount of attention for use at waste disposal sites. Instead of using barrier layers like conventional covers, percolation in ET cover system is minimized by water balance components which store the water prior to its transpiration through vegetation or evaporation from the soil surface. Vegetation for an ET cover must be suitable for its particular locality and have well-developed root systems, since they promote transpiration and contribute to the long-term performance of the cover. They pull water out of the cover soil and release it into the environment, thereby decreasing the percolation of …