Civil and Environmental Engineering Commons^™

Rehabilitation Of Timber Piles Using Fiber Reinforced Polymers Analyzed With Acoustic Emission, Rebekah Marie Krol

Theses and Dissertations

Assessing the current state of infrastructure and implementing strengthening or rehabilitation methods on old or damaged members is important to ensure safety and longevity of structures. Non-destructive testing is an important tool for localizing and characterizing damage in structures, especially structures that are more susceptible to damage because of age or environment. In addition to locating inadequate members, it is essential to have a repair technique in place so that the structure can continue to be used in a safe manner.

This study aims to review the use of acoustic emission for evaluating damage obtained in timber piles subjected to …

Physical Modeling Of Backward Erosion Piping Phenomenon In A Geotechnical Centrifuge, William Fernando Ovalle Villamil

Theses and Dissertations

Backward erosion piping is a mechanism of internal erosion that has been widely recognized as a potential hazard for water-retaining structures, such as dams and levees, that are founded on granular materials. Backward erosion piping initiates toward the downstream zone of the structure by the concentration of flow at an exit point acting as drainage, which leads to a localized loosening of the soil and eventually to a continuous migration of grains from the foundation following a piping path pattern. Such piping path extends backward toward the impoundment once a certain critical hydraulic condition is met, resulting in the loss …

Evaluation Of Concrete Bridge Decks Comprising Twisted Steel Micro Rebar, Aubrey Lynne Hebdon

Theses and Dissertations

The objective of this research was to investigate the effects of twisted steel micro rebar (TSMR) fibers on 1) the mechanical properties of concrete used in bridge deck construction and 2) the early cracking behavior of concrete bridge decks. This research involved the evaluation of four newly constructed bridge decks through a series of laboratory and field tests. At each location, one deck was constructed using a conventional concrete mixture without TSMR, and one was constructed using the same conventional concrete mixture with an addition of 40 lb of TSMR per cubic yard of concrete. Regarding laboratory testing, the conventional …

Developing A Cost Of Delay (Cod) Framework For The Dod & Analyzing The Current State Of Air Force Agile Cost Estimation, James Goljan

Theses and Dissertations

The study has two research objectives. The first research objective develops a proof of concept for a Cost of Delay (CoD) framework to evaluate the Air Forces Kessel Run Software Factory. CoD provides a means to justify and prioritize competing interests regarding budgetary, manpower, and overall strategic decisions. DoD organizations can employ a cost minimization framework to conduct CoD Analysis. The results demonstrate Software Factories eschew trends in the literature towards more complicated cost models that incorporate machine learning with Data-Based techniques in lieu of simpler models that utilize Engineering Build-up Capacity Based techniques.

Re-Aerosolization Of Dense Metal Oxide Simulating Radiological Contamination From Military Clothing, Joseph M. Chapman

Theses and Dissertations

Radiological contamination from nuclear accidents or the terrorist use of a Radiological Dispersal Device (RDD) are events that first responders must be prepared for. It is currently assumed that removal of the victims clothing will remove 80-90 of contamination. Many RDD radioisotopes produce dense aerosols that would then contaminate victim clothing and re-aerosolize during clothing removal. A series of experiments were conducted during which clothing was contaminated with a dense aerosol simulating the radioisotope of Strontium 90. Compared to background, there was statistically significant re-aerosolization from the clothing. This demonstrates inhalation hazards from re-aerosolization of RDD contamination.

An Analysis Of Various Hydrogen Production Methods For Fleet Vehicle Fuel, Eugene J. Denezza Ii

Theses and Dissertations

As conflict, the environment, and politics cause changes around the world, the United States Air Force is pursuing a diversification of drop-in and alternative fuel sources. Hydrogen fuel cells for vehicles are gaining popularity worldwide. Yet, how to best produce hydrogen gas still remains a question. This thesis will provide an overview of various hydrogen production methods and their respective environmental impacts, costs, efficiencies, and viability; and will perform sensitivity analysis to determine an optimal solution. The optimal production method is Thermolysis followed by Steam Reformation of Landfill or Natural Gas, Coal Gasification, and PEM Electrolysis. Based on varying requirements …

Hazard Mapping For Infrastructure Planning In The Arctic, Christopher I. Amaddio

Theses and Dissertations

Using modern high-resolution aerial photographs, LiDAR, historical aerial photographs, and facility data, a hazard mapping effort identified risks to infrastructure at Thule Air Base, Greenland, based on visible terrain features, surface hydrology, and slope; the distribution of these risks were then compared to existing foundation damage. The analysis indicated abundant and widespread geotechnical hazards at Thule Air Base and a weak relationship to existing foundation damage that requires more research to understand. The resulting hazard maps provide a critical tool for risk assessment and planning as well as a model for other locations to follow.

A Decision-Support System For The Deployment Tasking Process Of U.S. Air Force Civil Engineer Officers, Kenneth A. Neal

Theses and Dissertations

The Armed Forces frequently deploy their personnel to expeditionary locations around the world. For example, the Air Force tasks its personnel to deploy based on a six-month rotational cycle. In the current tasking process, the deployment makes its way down from combatant commanders to squadron commanders through the chain of command. The commander then has a few days to select an individual from their unit to fill the tasking. The commander may consider an individuals’ dwell time, home-station position, and upcoming significant life events; however, because commanders have little time and information, minimum requirements selection criteria often become the driving …

Decision Model For Additive Versus Conventional Construction In Remote Locations, Matthew R. Nicholson

Theses and Dissertations

Additive construction is a potential game changing innovative alternative to conventional methods with regards to structural integrity, timeliness, and waste reduction, especially in remote locations. While there have been numerous studies into the material science, additive construction will not be a viable alternative until a cost analysis is performed. This paper details the cost elements for both methods. Breaking down the key variables of material, logistics and transportation, and labor costs garner a better understanding of the cost difference between the two construction methods.

The Effect Of Molar Peroxide Ratio On The Oxidation Of Bisphenol A In An Ultraviolet Light Emitting Diode/Hydrogen Peroxide Advanced Oxidation Process, Megan C. Shade

Theses and Dissertations

Bisphenol A is a compound widely used in industry that is detrimental to human health and ecological systems. Ultraviolet light emitting diodes and hydrogen peroxide can be combined t produces hydroxyl radicals. These highly reactive radicals have the potential to degrade contaminants in water. This research utilized 50, 100, 250, 500, and 1000:1 H₂O₂:BPA molar ratios for analysis. These results illustrated that the reactions at the 50, 100, and 250:1 ratios were hydrogenperoxide limited. The 1000:1 results exhibited evidence of radical scavenging that limited the degradation of BPA.

Investigating Manufacturer Selection Decisions For Built Infrastructure Assets Using A Technical Performance Metric, Sarah L. Brown

Theses and Dissertations

Facility and built infrastructure asset management are necessary functions of any organization that utilizes buildings to operate their businesses. However, most organizations require facility managers to ensure the successful operation of their assets without providing sufficient resources to accomplish this task. Therefore, in resource-scarce environments, facility managers require data-driven solutions to manage their assets and make the best decisions. Facility managers need novel solutions to help make asset life-cycle decisions. This research provides such a solution. Capitalizing on available data, a technical performance metric is created, allowing facility managers to calculate their assets' operational performance. This performance metric provides a …

Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding

Theses and Dissertations

Legacy per- and polyfluoroalkyl substances (PFASs) exist in the form of aqueous film-forming foams within hangar fire suppression systems throughout the country, posing a threat to both surrounding environments as well as local populations. The United States (US) Department of Defense (DoD), in conjunction with the US Environmental Protection Agency (EPA), is investigating best practices to flush out existing contaminants prior to disposal and replacement with a less environmentally harmful replacement. While current procedures dictate a triple rinse of the entire system to yield contaminant levels acceptable to the DoD, the practice has never truly been tested. Designed as a …

Improving Airfield Pavement Degradation Prediction Skill With Local Climate And Traffic, Evan M. Fortney

Theses and Dissertations

Airfield pavements are a critical component of the global transportation network that provide a platform for national defense. Preventative and corrective maintenance activities are founded upon accurate expectations of degradation. The leading pavement management software creates degradation predictions from pavement groups using age as the IV and current state conditions as the DV. For this work, a framework is created and implemented that utilizes a PCR model to build upon accepted practices for degradation modeling to enhance and possibly augment future prediction capabilities. The model was applied to pairs of location and pavement family and reveals several findings: the selected …

An Empirical Analysis Of Dod Construction Task Order Performance, Adam B. Teston, Tyler S. Stout

Theses and Dissertations

Cost and schedule overrun plague over 50 of all construction projects, engendering diminished available funding that leads to deferred maintenance and impaired award ability for needed projects. Though existing research attempts to identify overruns sources, the results are inconclusive and frequently differ. Accordingly, this research reviews DoD construction contract data from the past ten years to identify the contract attributes of 79,894 projects that correlate with superior performance for use in future project execution. This research starts with creating a database that houses the largest single source of construction contract information. The research then evaluates the data to determine if …

The Effect Of Molar Peroxide Ratio On The Oxidation Of 2,4-Dinitroanisole In An Ultraviolet Light Emitting Diode Advanced Oxidation Process, Troy M. Searcy

Theses and Dissertations

Insensitive munitions (IMs) are increasingly employed by the U.S. military to prevent unintended detonations associated with conventional munitions. One IM used extensively is 2,4 dinitroanisole (DNAN). This research employed an ultraviolet light emitting diode (LED) and hydrogen peroxide advanced oxidation process (AOP) to treat DNAN-contaminated water at the laboratory scale. Five molar peroxide ratios (50:1, 100:1, 250:1, 500:1, 1000:1) were evaluated using the observed pseudo first-order rate constant as the performance metric. Both peroxide-limiting reactions and radical scavenging were observed over the range of ratios tested, with overall removal of DNAN decreasing above a ratio of 500:1.

Climate-Informed Prediction And Forecast Modeling Of Installation Total Energy Consumption, Scott C. Weiss

Theses and Dissertations

Climate variability is an external and stochastic factor that causes energy demand uncertainty. Energy managers can use climate-based models to understand future trends of energy demand and to adjust operations, policy, and budgets accordingly. This research focuses on 1) identifying how climate attributes impact energy use, 2) creating a historically informed statistical modeling framework to skillfully predict energy use, and 3) forecasting future changes to energy use and costs, using CMIP5 temperature projections, at the campus level. After synthesizing the existing breadth of research on climate-informed energy modeling, a skillful, unbiased, climate-informed total energy consumption prediction model is developed for …

Developing Infrastructure Adaptation Pathways To Combat Hurricane Intensification: A Coupled Storm Simulation And Economic Modeling Framework For Coastal Installations, Alexander J. Baldwin

Theses and Dissertations

Climate change projections suggest intensification of extreme weather events, including hurricanes, is expected throughout the 21st century. This will lead to increased destruction for coastal military bases unless infrastructure resiliency and adaptation measures are implemented. This research focuses on examining the simulation of probabilistic, climate-intensified hurricane events at Eglin Air Force Base. FEMA Hazus models are combined with climate projections for wind Intensity, tide, and sea-level rise to produce an assessment of losses to the installation. Damage estimates and hurricane intensity outputs are downscaled to the facility-level so that climate adaptation signals can be identified. The facility losses and climate …

Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch

Theses and Dissertations

A secure water source is essential to the resiliency and readiness of military installations and contingency operation locations, especially those located in the dry climates the US military operates in today. There are multiple issues of concern when identifying water sources, such as security, cleanliness, accessibility, and sustainability. Water resources pose a potential vulnerability to mission readiness in a remote, agile environment, such as a forward operating base (FOB). Having a secure water resource helps facilitate mission readiness in the contingency environment, offering the opportunity to be more resilient and cost-effective. Current water treatment technologies present the possibility to perform …

Conversion From Coal To Natural Gas At Wright Patterson Air Force Base: An Analysis And Case Study, Tyler A. Ferry

Theses and Dissertations

Over the last 20 years, natural gas has replaced coal as the preferred fossil fuel for heat and power generation across the United States, due to its increased prevalence, lower cost, and reduced environmental impacts. While most conversion decisions are driven by cost savings, proponents of energy transitions often cite emissions reductions as a tangential benefit. Over the same time, climate change and its impact on the environment and society have come to the forefront of scientific inquiry. One example of the transition from coal to natural gas can be found in Dayton, Ohio. Wright Patterson Air Force Base (WPAFB) …

Investigation Of The Load-Induced Cracking And Rutting Performance Of Specialty Hot Mix Asphalt Overlay Mixtures, Andrae Anthony Francois

Theses and Dissertations

This study was initiated with the aim of investigating the cracking performance, rutting performance, and cost effectiveness of specialty and composite HMA mixtures utilized in New Jersey to rehabilitate deteriorated rigid pavements. As such, four, plant-produced, specialty HMA overlay mixtures currently used in New Jersey were evaluated in this study. These overlay mixtures included: a dense-graded, 9.5-SP mixture, a gap-graded, 12.5-SMA mixture, a dense graded, 4.75-HPTO mixture, and a uniformly graded, 4.75-BRIC mixture. The 9.5-SP, 12.5-SMA, and 4.75-HPTO mixtures were produced using PG 76-22 binder while the 4.75-BRIC was contained a PG 70-28 binder. The laboratory cracking and rutting performance …

Multi-Skilled Labor Optimization With Partial Allocation Of Resources, Amira Saleh

Theses and Dissertations

The current practice of labor allocation in construction schedules assumes single-skilled workforce; meaning that each worker is assumed to be skilled in only one trade. In such practice, at any instance in the project lifecycle, some of the workforce become idle waiting for other labor types to complete their work. Traditionally, companies may relocate idle workers to other projects and return them back to their original project when needed again. This complicates the resource management process and is not often performed successfully, leading to schedule and cost overruns. Alternatively, project managers may keep the idle workforce at their projects because …

A Web-Based Change Control Management Toolkit For Lump-Sum Turnkey Contractors: Transformation To Third Generation, Ahmed Omran

Theses and Dissertations

Project deviations and changes are one of the key common particulars encountered in the Construction industry. Project changes can occur in different forms, may impact different pillars of the project, and can be caused due to the existence of various underlying factors. Mismanaging or lack of controlling these changes is one of the key contributing factors leading to project hardships. Contractors incur profit erosion, scope creep, and time slippages mainly by failing to have an effective project change management system enforced within its project execution philosophy. Such adversity is amplified for contractors engaging in lump-sum turnkey “LSTK” projects. Contractors encounter …

Development Of A Hurricane Recovery Function And Resilience Model For Single-Family Residential Homes, Uriel Robert Donald Clark

Theses and Dissertations

The resilience of communities, infrastructure, and the environment in the face of hurricanes has increasingly become of public interest in the wake of recent natural disasters and environmental activism. Previous methodologies have attempted to quantify resilience for various structures and scenarios. Many studies have primarily investigated the robustness of critical infrastructure (e.g., bridges, emergency facilities, and water systems) which are essential to the function of a community. However, few studies have applied this approach to individual residential buildings. Therefore, this research aimed to adapt the most recent recovery functions developed for residential homes by considering measurable factors that are known …

Using System Dynamics To Study The Effect Of Change Orders On Labor Productivity, Shrouk Gharib

Theses and Dissertations

Change orders in construction projects lead to numerous negative impacts, including loss of labor productivity, delays, and cost overruns. Owners and contractors are usually in disagreement when it comes to allocating the extent of responsibilities with respect to the resulting overruns. Each party tries to hold the other party fully responsible for such overruns through a series of claims and disputes. Several delay analysis techniques have been developed to aid in settling such disputes, however, they do not fully grasp the rippled impacts of change orders and do not assist parties in reaching consensus when it comes to finding the …

Performance And Efficiency Evaluation Of Stormwater Management Lids Using Pcswmm: Numerical Modeling And Sensitivity Analysis, Abdullah Al Fatta

Theses and Dissertations

Implementation of Low Impact Development systems (LIDs) can reduce the detrimental effects of urbanization. In this study, performance of both conventional drainage system and bioretention swales LID green infrastructure was assessed. Personal Computer Storm Water Management Model (PCSWMM) was used to investigate the performance by producing runoff hydrographs. Calibration and validation were conducted with independent storm events to minimize the gap between the simulated and observed outflow. Among different sensitive parameters, saturated hydraulic conductivity, suction head, percent initially saturated, Manning’s N for impervious area, were used in calibration. Each storm event resulted coefficient of determination (R2) values of 0.656 or …

Traffic Time Headway Prediction And Analysis: A Deep Learning Approach, Saumik Sakib Bin Masud

Theses and Dissertations

In the modern world of Intelligent Transportation System (ITS), time headway is a key traffic flow parameter affecting ITS operations and planning. Defined as “the time difference between any two successive vehicles when they cross a given point”, time headway is used in various traffic and transportation engineering research domains, such as capacity analysis, safety studies, car-following, and lane-changing behavior modeling, and level of service evaluation describing stochastic features of traffic flow. Advanced travel and headway information can also help road users avoid traffic congestion through dynamic route planning, for instance. Hence, it is crucial to accurately model headway distribution …

A Study On The Triaxial Shear Behavior Of Geosynthetic Reinforced Soil By Discrete Element Method, Md Wasif Zaman

Theses and Dissertations

A 3D DEM model using Particle Flow Code (PFC3D) software was developed utilizing a bonded-ball flexible membrane approach to study cohesionless soil as a discontinuous discrete material. The 3D model was calibrated and verified with experimental data, and a sensitivity analysis was carried out for the microparameters. Triaxial tests were simulated to observe the stress-strain curves and volumetric changes, as well as the strength parameters of soils consisting of spherical particles with different gradations but the same porosity. One important finding is that the relationships between particle size and deviatoric stress, internal friction angle, and dilatancy angle were found to …

The Optimization Of Efficiency And Infrastructure For Modern Potable Water Treatment Plants, Brent A. Dekock

Theses and Dissertations

The USDOE Industrial Assessment Centers (IACs) is a program that is designed to help small and medium-sized manufacturing facilities reduce their overall costs and improve energy efficiency. This includes improving potable water treatment plants which supply water throughout the country. This thesis covers the process of how IAC branches and water treatment facilities generally operate, as well as several assessment recommendations that have been developed by a branch of the IAC for several water treatment plants based in the Rio Grande Valley of Texas. The steps of the assessment and water treatment process are described, and several cost saving measures …

Development Of A Design Method For Bonded Concrete Pavement Overlays, Ahmed Alsabbagh

Theses and Dissertations

Several asphalt pavements prematurely reached the end of their design life due to wheel loading has dramatically increased on highways. Therefore, transportation and highways agencies often endeavor to provide high-performance pavement to ensure the longest life with low maintenance required. Although asphalt pavement overlay (APO) can provide a quick and low-cost option for pavements rehabilitation, it frequently exhibits excessive rutting especially at highway pavement subjected to stop-and-go traffic conditions. Hence, concrete pavement overlays (CPO) is one of the alternative options for rehabilitating deteriorated pavements. The ultra-thin white topping (UTW) is one type of concrete overlay types and is considered a …

Evaluation Of Accumulated Strain From Both Cyclic Triaxial And Static Creep Tests On Unbound Pavement Materials, Amir Mohammad Sajjadi

Theses and Dissertations

In this research, the behavior of Limerock (LR) aggregates blended with different reclaimed asphalt pavement (RAP) materials were investigated as an unbound base layer. Various combinations of LR and RAP, including 100%LR, 25%RAP75%LR, 50%RAP50%LR, and 100%RAP, were evaluated. Three main experiments performed on the samples were: static creep, static triaxial test, and cyclic triaxial test. The cyclic triaxial test was performed to measure the resilient modulus (MR) of materials. The results of the static triaxial test for 100% RAP showed that the deviator stress at failure steadily increased by increasing the confining pressure, while the 100% LR showed a maximum …