Civil Engineering Commons^™

Characterization And Modeling Of Asphalt Concrete For Dynamic Properties And Performances, A S M A. Rahman

Civil Engineering ETDs

The recently developed mechanistic-empirical pavement design guide (MEPDG, also known as Pavement M-E design method) uses the nationally calibrated, binder viscosity-based dynamic modulus predictive model for the design and analysis of asphalt pavements. In this study, this model is assessed for its appropriateness for asphalt-aggregate mixtures typically used in New Mexico. In essence, this study investigates the predictability issue of complex modulus of New Mexico mixes. A total of 54 Superpave mixes with different aggregate gradations, air voids, and binder grades were collected from the mixing plants and from the pavement construction sites. The loose asphalt mixtures were then compacted, …

Multi-Hazard Performance Assessment Of High-Rise Buildings, Jad El Khoury Antoun

LSU Master's Theses

In the last few decades, there has been an important increase in building high-rise constructions in many cities around the world. Since they offer several benefits in populous areas in terms of space efficiency, economy and sustainability, tower buildings attracted practitioners and researchers to understand better their exclusive behavior and response to natural hazards (e.g., hurricanes, earthquakes). Because of their flexibility and their commonly limited damping, skyscrapers are more susceptible to wind and earthquake actions than low- and mid-rise buildings. Moreover, many locations are prone to multiple hazards; hence, it is important to understand thoroughly the structural behavior of structures …

On The Fatigue Of Headed Shear Studs In Steel-Concrete Composite Bridge Girders, Brianna Laurene Ovuoba

Graduate Theses and Dissertations

Shear connectors are commonly used in steel bridges to join the concrete deck and steel superstructure, providing a mechanism for shear transfer across the steel-concrete interface. The most common shear connector is the headed shear stud. In the current AASHTO LRFD Bridge Specifications on composite design, shear stud fatigue often governs over static strength, and a large number of shear connectors often result. This dissertation investigates headed shear stud fatigue capacities and demands, and provides insight into conservancies in existing design specifications through examination of existing high-traffic bridge performance.

To investigate stud capacity, a total of six high-cycle fatigue tests …

Investigating Fate Of Silver Nanoparticles In Wastewater Biofilms, Connie Marie Walden

Graduate Theses and Dissertations

As industrial advances make everyday life easier for human kind, the processes by which we need to maintain sanitary conditions for both water and wastewater treatment will become increasingly complex. Innovations in food packaging and textile design incorporate engineered nanoparticles (ENPs) to increase antimicrobial properties of clothing, maintain product color, and keep food in packaging from spoilage. For most products, ENPs released will enter the sanitary sewer system, and ultimately wastewater treatment plants. Biofilms grow universally on surfaces where a protective layer of extracellular polymeric substances (EPS) shields attached cells from stressors. In wastewater treatment, complex biofilms are utilized as …

Cost-Savings Of Implementing Site-Specific Ground Motion Response Analysis In Design Of Mississippi Embayment Bridges, Ethan Ryan Benton Baker

Graduate Theses and Dissertations

Deep dynamic site characterization and a site-specific ground motion response analysis (SSGMRA) were conducted for a bridge site in Monette, Arkansas. The SSGMRA indicated the design acceleration response spectrum determined using the American Association of State Highway and Transportation Officials (AASHTO) general seismic procedure could be reduced by 1/3 for the short period range due to attenuation of the short-period ground motions. The steel girder pile-bent bridge, originally designed using the AASHTO general seismic design procedure, was redesigned using the updated seismic demands estimated from SSGMRA. A cost-savings analysis was then conducted to determine the potential savings associated with conducting …

Development Of An Internal Camera-Based Volume Determination System For Triaxial Testing, Sean Elliott Salazar

Graduate Theses and Dissertations

Accurate measurement of axial, radial, and volumetric strain parameters are critical to the understanding of phase relationships and the constitutive behavior for saturated and unsaturated soils. The use of photographic monitoring techniques for laboratory-based measurement of these parameters have become common. A novel technique that utilized camera instrumentation located within the triaxial testing cell was developed and validated. By placing the instrumentation inside of the cell, instead of the instrumentation being located outside of the cell, the technique eliminated cumbersome corrections required to account for optical distortions due to 1) the refraction of light at the confining fluid-cell wall-atmosphere interfaces, …

Automated Pin-Dot Marking Effects On A709-Gr50 Steel Plate Fatigue Capacity, Michael Andrew Noernberg

Graduate Theses and Dissertations

During fabrication of multi-piece steel bridge assemblies, markings are often made on the steel surface to identify/track individual pieces or to provide reference for fabrication layout or later erection. Automated marking methods such as computer numerically controlled (CNC) pin-dot marking offer fabrication efficiencies; however, for marked steel sections subjected to frequent or repeated loading (i.e. bridge girders) many code specifications require experimental testing to verify any marking effects on fatigue capacity. In this study, the effects of automated pin-dot markings on the fatigue capacity of A709-Gr50 bridge steel are experimentally investigated from 13 specimens considering 2 marking frequencies (corresponding to …

An Evaluation Of Borehole Hydraulic Conductivity Equations And Field Determined Soil Water Characteristic Curves, Johnathan Dale Blanchard

Graduate Theses and Dissertations

The methods utilized to determine the hydraulic conductivity of compacted clay liners (CCLs) are of importance for safe guarding the environment from landfill leachate. Therefore, the methods utilized in the analysis of the Two Stage Borehole (TSB) test, as described in the ASTM D6391-11 (Method A, B, and C) standard, were evaluated. Data from hydraulic conductivity tests, as performed on three test pads, were utilized to review the ASTM D6391-11 equations. Additionally, two test pads were instrumented with volumetric water content and soil water matric potential sensors to facilitate the determination of field-obtained soil water characteristic curves (SWCCs) and hydraulic …

Evaluation Of Water Resources And Hydraulic Influences In The Restoration Of The Western Part Of The Mesopotamian Marshlands, Ali Kareem Al-Quraishi

Graduate Theses and Dissertations

The purpose of this study is to assess the water resources and water conveyance system of the western part of the Mesopotamian marshes (Al-Hammar marsh) as well as develop a water conveyance system to distribute water throughout the western Al-Hammar marsh. These processes are significant to identify the current restoration problems and help to create restoration strategies for the marsh. Also, proper management strategy to the Al-Hammar marsh is necessary to preserve the marsh ecosystem, irrigate lands, and provide domestic necessities in the villages.

The overall project is divided into three main chapters which address the current ecological and hydrological …

An Investigation Of Employment And Wage Distribution In The Construction Industry By Race/Ethnicity And Gender, Binit Kumar Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

One of the largest job providers in the U.S, is the construction industry, an industry that suffers from critical problems pertaining to a labor shortage. Yet the industry also struggles with insufficient interest and inconsistent participation from underrepresented demographic groups. To address the issue of workforce income inequality and bias, the industry must better understand the current situation regarding inequality; it needs to pinpoint some basic problems. To do so, analysts must scrutinize the following aspects: 1) the current differences within the construction workforce by race/ethnicity and gender with regards to the total employment and 2) the current disparity within …

Non-Destructive Evaluation Of Soil Moisture In Evapotranspiration Cover System, Md Ishtiaque Hossain

Civil Engineering Dissertations

A conventional landfill cover system is designed as a barrier layer system, with low hydraulic conductivity, to minimize the percolation of water from the cover to the waste. Evapotranspiration (ET) covers are currently becoming a popular alternative that are acceptable to landfill authorities, due to their cost effectiveness and nature-friendly performance. The principle function of the ET cover is to store the infiltrated water, using the water balance technique, until it is transpired by plants into the atmosphere, thus minimizing percolation. The performance of the final cover system is assessed by monitoring the soil moisture in the ET cover and …

Shear Behavior Of Synthetic Fiber Reinforced Concrete Box Culverts, Mahnaz Mostafazadeh

Civil Engineering Dissertations

This research pursues a comprehensive experimental study on the shear capacity of zero-slump, dry-cast Synthetic Fiber-Reinforced Concrete (SYN-FRC) with the aim of reducing or even eliminating stirrups in box culverts. Since using stirrups in structures such as box culverts need labor work and cause reinforcement congestion, eliminating or reducing stirrups in design, prevent poor-quality concrete, help better concrete compaction and could save manufacturer time and money over the years. This study first determined the shear capacity of synthetic fiber concrete matrix by varying fiber volume fraction. Then, FEA and full experimental tests have been conducted to evaluate the effect of …

Non-Linear Analysis Of Steel Fiber Reinforced Concrete Hollow Columns Under Uniaxial Bending, Mohammed Huzaifa Ghori

Civil Engineering Theses

This study investigates the performance of Steel Fiber Reinforced concrete hollow columns under axial compressive load and uniaxial bending with varying amounts of steel fiber using Finite Element Method of Analysis. The columns are of two groups, one with a 10% void and the other group has 20% void at the center. Each group’s specimens’ fiber content is varied in 0.5% increments from 0 to 1.5%. Also, the collapse load of the columns was obtained. Numerical results were compared with the available experiments. Two parametric studies were conducted by varying the amount of void percentages and steel fiber contents. In …

Experimental Study On Resilient Behavior Of Geocell-Reinforced Recycled Asphalt Pavement Base Layer: Model Development, Manikanta Saladhi

Civil Engineering Theses

Recycled Asphalt Material (RAP) is defined as removed and reprocessed pavement materials containing asphalt and aggregates. These materials are obtained when asphalt pavements are removed for the rehabilitation and maintenance of distressed pavements. The use of RAP as a base/subbase aggregate in pavement construction is technically and environmentally a sustainable solution, and conserve use of natural resources by requiring less virgin aggregate in pavement construction. Past studies showed that the use of 100% RAP as base course lacks shear strength and can undergo large deformations. Geocells are a system of three-dimensional, interconnected, honeycombed cellular structures that resist the lateral expansion …

Fatigue Impacts On Hdpe Pipe Material Properties, Marjan Shahrokh Esfahani

Civil Engineering Dissertations

During a pipe’s life cycle, failures occur due to numerous factors such as age, loading conditions, environmental conditions, installation quality, manufacturing procedures, operation and maintenance strategies and so on. Frequent pressure surges or fluctuations in a piping system may cause a fatigue failure as fatigue is one of the most important issues in water pipes due to water hammer impacts. Application of buried High Density PolyEthylene (HDPE) water pipelines has significantly increased in recent years, and PE4710 is a new member of HDPE family. So, there is not yet enough information about PE4710 long-term performance. Due to lack of enough …

Evaluation Of Plant Root On The Performance Of Evapotranspiration (Et) Cover System, Md Jobair Bin Alam

Civil Engineering Dissertations

The performance of an evapotranspiration (ET) cover for a landfill exceeds that of a conventional landfill final cover. Its low percolation and high evapotranspiration rely on the properties of unsaturated soils, the energy demands of plants, and the atmosphere. Plant roots pull water out of the cover soil and release it into the environment, thus managing water in a much more natural way than the conventional cover, where water is controlled by creating a physical barrier. Therefore, plant roots are a significant component in the optimization of ET cover performance. In recent years, a great deal of effort has been …

Seismic Performance Of Double-Channel And Double-Hss Sections, Special Truss Moment Frame With Buckling Restrained Braces, And Long Span Special Truss Moment Frame, Chatchai Jiansinlapadamrong

Civil Engineering Dissertations

Until recently, all special truss moment frame (STMF) experimental research was done on only double angle STMFs. In order to satisfy the code seismic drift limitation, especially for mid-rise and tall multistory buildings, a large column section is needed, when double angle sections are used. However, heavy chord members can be used in this instance. Due to configuration of STMFs, the chord members in the special segment of an STMF experience higher rotational demand than the story drift. As a result, there is a need to verify large rotational capacity of other heavy steel shapes. Recent analytical investigation and experimental …

Quantitative Non-Destructive Evaluation (Nde) Of Frp Laminate-Concrete Bond Strength, Mina Riad

Civil Engineering Dissertations

Repair and rehabilitation methods for civil infrastructure have become a topic of great interest to engineers. Fiber Reinforced Polymer (FRP) is considered as one of the most popular and practical solutions for strengthening and retrofitting of civil infrastructure. Several past studies indicated that significant increase in strength and stiffness can be achieved by using this technology. The FRP-concrete interface bond is critical in transferring stresses from the concrete surface to the FRP. However, the evaluation of the bond strength is still a challenging issue. To evaluate the bond strength using non-destructive techniques, 32 concrete beams strengthened with FRP using different …

A Thermal Inertia Approach To Precision Irrigation Using Unmanned Aerial Vehicles Coupled With High-Resolution Multispectral Imagery, Kevin James Wienhold

Civil Engineering Theses

Soil moisture is a critical variable in the optimization of irrigation scheduling in water resources management. Despite using tens to hundreds of thousands of gallons of water each day, many golf courses rely on a sparse network of point measurements to estimate irrigation requirements for turfgrass management. This study describes a novel system known as Precision Irrigation Soil Moisture Mapper (PrISMM) in which an unmanned aerial vehicle equipped with multispectral sensors is used to estimate volumetric water content (VWC) at a golf course using a thermal inertia approach. PrISMM consists of three central components, including (1) high-resolution thermal and optical …

Performance Of Light-Frame Wooden Structure (Lfws) Subjected To Combined Wind And Flood Hazards, Ajay Baniya

Civil Engineering Theses

Light Frame Wooden Structures (LFWS), which are more prone to wind damage by virtue of their light weight, sustain severe damage when they are subjected to simultaneous flood and wind. A difficulty in Multi-hazard design for wind and flood is that the load and resistance factor make use of different design philosophies developed by different sub-disciplines. After Multi-hazard events, in most cases, it is complicated to determine the sole damage done by flood or wind alone. The load path of Wooden structure is already ambiguous, the addition of flood characteristics makes the analysis and design process more complicated. It has …

Effects Of Climatic Loading In Flexible Pavement Subgrades In Texas, Asif Ahmed

Civil Engineering Dissertations

Expansive soils, which have been reported as a worldwide problem, cover 25% of the United States. Due to the swelling and shrinkage behavior induced by moisture variations, expansive soil contributes to volumetric deformation, which in turn affects the stability and performance of structures. The Texas Department of Transportation (TxDOT) allocates 25% of its budget to pavement maintenance and repairs, much of which is triggered by expansive soil. In order to decrease the burden of this expense on maintenance authorities, it is necessary to have an accurate understanding of expansive subgrade behavior. Applying this knowledge to the pavement design and construction …

Improvements To The Duplicate Shear Tester, Yazeed Suleiman Jweihan

Civil Engineering Theses

Rutting in the asphalt concrete layer is a major distress in flexible pavements caused by the permanent shear deformation in asphalt mixes. The shear deformation is induced by heavy truck axis during hot summer days. Rutting affects directly the safety and users comfort. Therefore, developing of an appropriate test device for measuring the fundamental shear properties of asphalt mixes is important in order to improve the rutting resistance of asphalt mixes and pavement performance. The desired device should be simple, inexpensive, and accurate to be able to be incorporated for a quality control or quality assurance process, as well as …

Aermod Modeling Of Air Pollutant Emissions From Backup Generator Use In Lagos, Nigeria, Temitope Abayomi

Civil Engineering Theses

Generator emissions contribute to increase in air pollution. In developing countries with inadequate electricity supply, many people rely on back-up generators for long-term electricity supply. Nigeria is the second biggest importer of generators in Africa. As of 2009, it was estimated that 60 million people in Nigeria owned and operated small to medium size generators to provide electricity for their daily use. The sheer number of generators in use suggests that generator emissions are a significant source of air pollution in the country, particularly in urban cities. In this work, the concentrations of pollutants emitted from 50 generators in a …

A Standard Tensile Testing Procedure For Fiber-Reinforced Concrete (Frc) And Ultra-High-Performance Fiber-Reinforced Concrete (Uhp-Frc) Based On Double Punch Test (Dpt), Shuveksha Tuladhar

Civil Engineering Theses

Current test methods such as ASTM 1609, ASTM 1550 and direct tensile test are used for evaluating the mechanical properties of Fiber Reinforced Concrete (FRC) and to determine the quality of mixture in design and construction practice. These test methods show high variability in the results, requires large specimen and complicated test setup. An ideal material test method for FRC should give consistent results in determining mechanical properties such as peak strength and residual strengths. Moreover, current test methods are expensive and time-consuming as more specimens are needed to acquire reliable test results. Double Punch Test (DPT) is a simple, …

Development Of A Production Estimation Model For Tunnel Boring Machines (Tbms), Saeed Janbaz

Civil Engineering Dissertations

Advance rate (AR) estimation is a crucial factor at the conceptual phase of a tunneling project for preliminary estimation of tunnel boring machines' (TBMs') usage. The primary objective of this research is to develop order of magnitude performance charts for advance rate of TBMs that can be used using the limited information about the tunneling progress at the conceptual phase. The secondary objective of this dissertation is to evaluate factors that impact TBM progress in large diameter applications. Tunnel diameter and uniaxial compressive strength of ground are found to be some of the primary parameters for prediction of advance rate. …

Transformation Of Nonlinear Waves In The Presence Of Wind, Current, And Vegetation, Haifei Chen

Electronic Theses and Dissertations

Accurate prediction of extreme wave events is crucial for the safe maritime activities and offshore operations. Improved knowledge of wave dissipation mechanisms due to breaking and vegetation leads to accurate wave forecast, protecting life and property along the coast. The scope of the thesis is to examine the wave transformations in the presence of wind, current, and vegetation, using a two-phase flow solver based on the open-source platform OpenFOAM. The Reynolds-Averaged Navier-Stokes (RANS) equations are coupled with a Volume of Fluid (VOF) surface capturing scheme and a turbulence closure model. This RANS-VOF model is adapted to develop a numerical wind-wave-current …

Development Of Pre-Stressed Retrofit Strategies For Mitigating Fatigue Cracking In Steel Waterway Lock Gate Components, Christine Michelle Lozano

Graduate Theses and Dissertations

Lock gates are an important part of the transportation infrastructure within the United States (US), having many economic, safety, and environmental benefits over rail and highway transportation systems. Unfortunately, many existing lock gates throughout the US have reached or exceeded their initial design life and require frequent repairs to remain in service. Unscheduled repairs often increase as gates age, having a local economic impact on freight transport which can create economic ripples throughout the nation. Fatigue and corrosion are key causes of unscheduled service interruptions, degrading lock gate components over time. Additionally, because lock gates are submerged during operation, crack …

Dem Study Of A Single Stone Column In A Clayey Stratum, Anibal Enrique Santos

Graduate Theses and Dissertations

Aggregate piers are an alternative ground improvement technique used for improving the bearing capacity and reducing the total and differential settlement of foundations supported on compressible soils. The piers are composed of a series of vibrationally compacted aggregate lifts from a desired depth up to the finished foundation level. The shear strength of the coarse-grained material comprising an aggregate pier is defined by its internal friction angle. There are several factors affecting the friction angle of the granular material that include: confining stress, particle shape, relative density and particle distribution (gradation). These factors are not directly considered in the design …

Using Historic Pavement Performance Data To Identify And Select Sites For Asphalt Mixture Design Studies, Allyson Richey

Civil Engineering Undergraduate Honors Theses

Since 1997 Arkansas asphalt mixtures have been designed using a procedure commonly known as ‘Superpave’. In a traditional Superpave mix design, the design considers only traditional volumetric parameters; however, recent advances in mix design technology emphasize mixture’s ability to perform in its environment. There are numerous factors which affect the performance characteristics of an asphalt mix. Certainly, the asphalt binder’s performance is a critical variable in this system. Asphalt binders are sensitive to temperature, so much so that their primary parameter on which they are recommended is a function of both temperature and the geographic latitude in which the pavement …

Evaluating The Effectiveness Of A Hybrid Geosynthetic Reinforcement System To Mitigate Differential Heave On Flexible Pavement Due To Expansive Subgrades, Mir Md. Tamim

Boise State University Theses and Dissertations

Transportation industries encounter substantial challenges with respect to ride quality and serviceability when they deal with expansive soils underneath roadway structures. These soils exhibit swell-shrink behavior with moisture variations, which cause surficial heaving on the pavement structure and cost billions of dollars for the maintenance of pavements. For the past four decades, a particular stretch of US-95 (Oregon line to Elephant Butte) exhibited recurrent swelling distresses due to the underlying expansive soils. Despite remedial measures that exhibited satisfactory results for most of the sections, recurrent damage still continued in few sections. Further research indicated that the problematic soils were located …