Civil Engineering Commons^™

Erosion And Resuspension Of Cohesive Sediments In Coastal Louisiana, Laith Qasem Shamaileh

University of New Orleans Theses and Dissertations

The research presented in this study is motivated by the need to improve the predictions of cohesive sediment erosion and subsequent transport. In addition, the knowledge of the geotechnical engineering soil properties related to the erosion of sediments in coastal Louisiana has broad implications as these properties are used in transport models guiding the current restoration efforts. The erosion measuring device used in the study is the Cheng-Han Tasi and Wilbert Lick Shaker. Previous studies have been conducted before using the Shaker, but challenges with the calibration of the shear stress hampered the resuspension results produced by the Shaker. Therefore, …

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 …

Minimizing Surface Run-Off, Improving Underground Water Recharging, And On-Site Rain Harvesting In The Kathmandu Valley, Ambika P. Adhikari, Keshav Bhattarai

Himalayan Research Papers Archive

Nepal's political institutions and administrative units were thoroughly restructured in 2015 with the promulgation of the new Constitution. Several rural areas were combined to meet the definition of urban threshold criteria to classify rural areas into urban categories. Accordingly, over 3,900 local political and administrative units were amalgamated into 753 units, of which, 293 units are classified as urban. Within these newly defined urban areas, many natural environments have been converted into impervious surfaces such as paved roads, sidewalks, and building roofs. These impervious surfaces have drastically increased the amount of surface run-offs-often termed as "urban floods"--under increasing precipitation caused …

Correlations Between Dynamic Probe Blow Count And Undrained Shear Strength For Peat At A Well-Characterised Raised Bog In Ireland, David Mchugh, Ciaran Reilly, Juan Pablo Osorio

Articles

Peat deposits are generally heterogeneous, with large variations over small areas. Peat has an extremely high water content, high compressibility and low shear strength. This presents a major issue in studying the geomechanical behavior of peat. For this study, field and laboratory tests were conducted to establish the undrained shear strength (s_u) of peat at a cutover industrial peatland in Ireland which had been extensively characterized in the past. The new field work included TRL-type Dynamic Cone Penetrometer, Mackintosh probe and field vane shear tests. A correlation was developed between the Mackintosh probe “M-value” blow count and the …

Development Of Deep Shear Wave Velocity Profiles And An Approach To Generate Site Signature Consistent Pseudo Shear Wave Velocity Profiles In The Mississippi Embayment, Ashraf Kamal Himel

Graduate Theses and Dissertations

This dissertation details the development of a surface wave method (SWM) technique to generate deep shear wave velocity profiles (VS profiles), applying this technique at 24 sites across the Mississippi embayment and developing an approach to generate pseudo site signature consistent VS profiles from velocity functions and fundamental frequency. In the presented SWM technique, active and passive source surface wave measurements are inverted along with fundamental frequency to develop a site signature consistent VS profile. Multiple transformation methods, including MSPAC, HRFK and FK are used to resolve experimental dispersion data from surface wave measurements. SWM VS profile at the Central …

Performance And Ultimate Limit State Of Large-Span Soil-Steel Structures, Kareem Embaby

Electronic Thesis and Dissertation Repository

This thesis investigates the structural behavior and soil-structure interaction mechanism of large-span soil-steel structures utilizing steel plates with the deepest corrugation profile, 500 mm X 237 mm. The world’s largest-span soil-steel bridge, with a span of 32.40 m, was constructed using 12 mm thick steel plates with the deepest corrugation profile and was instrumented extensively to monitor the displacements and straining actions of the steel structure. Lateral reinforcement steel mesh was attached to the steel structure and the ends of the structure were strengthened by circumferential reinforced concrete collars. Three-dimensional (3D) nonlinear finite element (FE) model was conducted and validated …

Evaluation Of An Equivalent Mean Grain Size Diameter To Rationally Predict The Erodibility Of Fine Riverbed Soils In Nebraska, Basil Abualshar

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The erosion of riverbed soils under the bridges is one of the major reasons that cause bridge closure or failure leading to a significant effect on the local economy. One of the commonly used methods to predict the erosion rate of soils is the excess shear stress method, which is based on two parameters describing the erodibility behavior; the erodibility coefficient and the critical shear stress. On the other hand, studies showed that the mean grain size diameter D₅₀ could be correlated to the erosion resistance of soils, usually for cohesionless soils but not for cohesive soils. It is …

Feasibility Report On Water Recycling And The Housing Crisis, Tally A. Perry

City and Regional Planning

The western United States is experiencing increasing population, a housing shortage, and a drought. These challenges demand creative and unprecedented changes to development. Water recycling is slowly emerging as a viable solution for developers, home owners, and cities as a way to continue much-needed housing development while mitigating unnecessary water depletion. With all change, policy, feasibility, and awareness can be the largest influencers. Drought-ridden western-American states require additional and revised regulatory requirements to promote recycled water in new development. Currently, water reuse is largely used for agricultural and industrial purposes. To motivate and encourage housing development, water recycling needs to …

Performance Of Fouled Railroad Superstructure Subjected To Traversing Heavy Haul Trains, Majid Kh Touqan

Electronic Thesis and Dissertation Repository

Railway transportation offers capacity, efficiency, and safety to serve the needs of modern societies for moving freight and people. Therefore, the sustainability and safety of railroad infrastructure are of paramount importance for securing transportation needs. Freight train passby loads increase the surface deformation of railroad substructure due to cumulative plastic strains, which lead to surface deviation of the railroad tracks. Correspondingly, railroad maintenance is necessary to sustain track geometry alignment and to prevent deterioration of the sub-structure over time, which can increase operating costs significantly. Therefore, this thesis evaluates the performance of fouled railroad superstructure through laboratory testing of fouled …

A Review Of Current Construction Guidelines To Inform The Design Of Rammed Earth Houses In Seismically Active Zones, David Thompson, Charles Augarde, Juan Pablo Osorio

Articles

Sustainability in the materials we use for construction is a prime concern, focusing on reducing the embodied energy and carbon footprints of the materials used. The cement used in concrete products is responsible for a significant proportion of Man's CO2 emissions and its production requires substantial energy input, as do fired clay products. For this reason, products formed from unfired earthen materials are of increasing interest and the current challenges include devising means of robust design for strength and to address durability concerns. One form of earthen construction that employs an in-situ method is rammed earth, and it is a …

Rapid Non-Nuclear In Situ Density And Moisture Content Measurement Of Soil, Mateo Lopez

Graduate Theses and Dissertations

Adequate soil compaction is important for the stability and safety of structures and transportation infrastructure. Thus, methods utilized to obtain properties that control the quality of compaction in the field are essential to ensure proper construction. These properties include; total density, dry density, total unit weight and dry unit weight of the compacted soil. The most common method to measure these properties in the field is the Nuclear Density Gauge. Moisture content and density results are obtained using the Nuclear Density Gauge in one to four minutes. However, this method requires specialized training and strict storage requirements in addition to …

Cyclic Behavior Of Laterally Skewed Special Moment Frame Connections: Experimental Testing And System-Level Analyses, Mohammad Hossein Kashefizadeh

Graduate Theses and Dissertations

Special moment frames (SMFs) are frequently used in high seismic areas for architecturally constrained designs. SMFs provide lateral system stiffness without the use of braces that often obstruct views and architectural features. Current American Institute of Steel Construction (ASIC) provisions (AISC 341-16) provide prequalified SMF connection details; however, all prequalified details only consider orthogonal connections between the beam and column. This dissertation investigates the effect of adding skew within SMF beam-to-column connections. The study presented herein involves system-level dynamic time-history analyses of skewed SMF connections, the analytical component-level investigation into the effect of the concrete slab on behavior of the …

Experimental And Numerical Analysis Of Soil-Geosynthetic Composite For A Geosynthetic-Reinforced Roadway System, Daniel Robertson

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The present research conducted tests to evaluate the reinforcing performance of geosynthetics including three geogrids (GG1, GG2, and GG3) and one geotextile (GT) for three different soil types – sand, clay, and red shale. All geosynthetics showed great improvement under the lowest confining pressure. The report concluded that between the Large-Scale Direct Shear test, the Large-Scale Pullout Box, and the FLAC simulation, the three geogrids showed the greatest improvement when conducted with sand. The sand could withstand a much greater normal pressure than either clay or red shale. The biaxial geogrids, GG1 and GG3, had ideal results for lower stress …

University Of Tennessee Outdoor Cultural And Recreational Center, Meredith King

Chancellor’s Honors Program Projects

No abstract provided.

Hydropower System Design In Nazarét, Panama, Claudia M. Bible, Matthew J. Tolson, Andrew Houser, Aj Condra, Nathan Smith

Chancellor’s Honors Program Projects

No abstract provided.

University Of Tennessee Outdoor Cultural And Recreational Center, Meredith King

Chancellor’s Honors Program Projects

No abstract provided.

Investigation Of Groundwater Depletion And Leveel Underseepage With Unstructured-Grid Modeling Approach, Ye-Hong Chen

LSU Doctoral Dissertations

Unstructured grid is a tessellation of geometric shapes in irregular patterns that provides flexibility in grid design for groundwater modeling. However, groundwater modeling is mostly developed with uniform grid tessellation and layer, which could simplify model structure or cause expensive computational costs in high-resolution simulations. Unstructured grid incorporates non-uniform horizontal and non-uniform vertical discretizations providing the capability to replicate complex hydrostratigraphy, capture geologic features that are crucial for groundwater flow simulation, and reduce computational costs while maintaining a high resolution for areas of interest. This study contains three parts to investigate unstructured-grid approach on constructing high-fidelity groundwater models, comparisons with …

Influence Of Foundation Damping On Offshore Wind Turbine Monopile Design Loads, Wystan Carswell, Sanjay R. Arwade, Jörgen Johansson, Don J. Degroot

Publications

The dynamic behavior of offshore wind turbines (OWTs) must be designed considering stochastic load amplitudes and frequencies from waves and mechanical loads associated with the spinning rotor during power production. The proximity of the OWT natural frequency to excitation frequencies combined with low damping necessitates a thorough analysis of sources of damping; of these sources of damping, least is known about the contributions of damping from soil-structure interaction (foundation damping). This paper studies the influence of foundation damping on cyclic load demand for monopile-supported OWTs considering the design situations of power production, emergency shutdown, and parked conditions. The NREL 5 …

North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev

Honors Theses

The following project report was a study of the North 14^th Street corridor ranging from Adams Street to Virginia Street conducted by University of Nebraska-Lincoln students for a senior design capstone project. Main focuses of the project were the intersection of Adams and 14^th Street and the 14^th Street bridges over Cornhusker Highway and Oak Creek. Study of this area included work in transportation, traffic, structural, geotechnical, water resources, and environmental engineering. However, this report done by students should not take the place of work done by licensed professional engineers.

This project was done in collaboration with …

Development Of A Decision-Making Tool For Prediction Of Rainfall-Induced Landslides, Faisal Shakib Ahmed

Theses and Dissertations--Civil Engineering

Landslides are frequently observed in mountainous places following prolonged periods of rain, frequently resulting in substantial topography changes. They pose a significant risk to human lives and the built environment globally, particularly in areas prone to excessive rainfall. While slope failures can occur because of human-caused factors such as slope loading or toe cutting for construction purposes, many failures occur because of rainfall penetrating an otherwise stable slope. A greater understanding of the characteristics and mechanics of landslides is consequently critical for geotechnical research, particularly in evaluating prospective mitigation strategies. The potential of slope failure is a primary consideration when …

Spatiotemporal Analysis Of Taxi And Transportation Network Companies (Tnc) Demand In The Wake Of Covid-19, Dewan Ashraful Parvez

Electronic Theses and Dissertations, 2020-

The objective of the thesis is to understand the factors affecting spatiotemporal ridehailing demand patterns as the COVID-19 pandemic has evolved. Specifically, the current study examines the key contributing factors of weekly ridehailing demand by employing Taxi and Transportation Network Companies (TNC) trip data from January 2019 through December 2020 for New York City. The ridehailing demand is partitioned across four time periods including Morning Peak, Morning Off Peak, Evening Peak and Evening Off Peak to accommodate for the time-of-day specific variations. Drawing on the high-resolution NYC data, the current study developed pooled spatial panel models to accommodate for the …

Non-Destructive Characterization Of Bio-Cemented Soils Via Seismic Wave Measurement, Kyle Best

Williams Honors College, Honors Research Projects

The final outcome of this project is to examine the mechanical and resulting physical properties of bio-treated soil through microbial activity via non-destructive testing by seismic waves. The proposed bio-treatment strategy is through supplying specific nutrients for indigenous microbes within a soil specimen which in return produce calcium carbonates. The bio-minerals produced during these biogeochemical activities will improve the mechanical properties of soil by making cementation between soil grains. Additionally, a theoretical laboratory experimentational description will be provided to explain any associative effects on a specimen's water permeability or mechanical strength due to bio-mineralization within the samples. The characterization of …

Load And Pressure Distribution As A Function Of Dynamic Contact Stress At The Railroad Crosstie-Ballast Interface, Habib Abdil Unluoglu

Theses and Dissertations--Civil Engineering

Excessive crosstie wear and abrasion and ballast wear and fouling are two of the fundamental problems contributing to inadequate railroad track performance. This adversely affects the attainment and long-term maintenance of desired track geometric requirements. The magnitudes and distribution of the stresses at the crosstie-ballast (CT-B) interface must be known to determine the stress distribution on the ballast. However, the stresses at the top of the ballast often vary significantly. This study examines a new approach to predicting dynamic contact pressures at the interface of crosstie and ballast using the ‘square wave theory.’ A data set of in-track CT-B interfacial …

Crystalline Analysis Of Geomicrobially-Induced Calcium Carbonate Precipitation In Sands Using A Surface Percolation Treatment Technique, Justin Edward Mulloney

UNF Graduate Theses and Dissertations

Ottawa 50/70 sand specimens and natural beach sand samples were treated using bio-augmented geomicrobies via a surface percolation technique. Testing was conducted on these specimens to determine how resultant calcium carbonate precipitation changed as a function of temperature, depth from the surface, and in the presence of magnesium. Specifically, x-ray Diffraction (XRD), a Scanning Electron Microscope (SEM), and Energy Dispersive X-ray Spectroscopy (EDS) were used to determine and quantify the presence of calcium carbonate and its associated phase. Results showed a direct relationship between temperature and precipitated calcium carbonate. In addition, as an unintended consequence associated with the treatment, ammonium …

Analysis Of Shear Failure In Ultra-High Performance Concrete Beams, Kevin Conway

Electronic Theses and Dissertations, 2020-

Ultra-high performance concrete (UHPC) is an emerging cementitious material type currently undergoing research in different structural applications. This material is characterized by a compressive strength of 150 MPa (22 ksi), according to the Association Francaise de Genie Civil and the Federal Highway Administration, high tension strength, and high durability. Additionally, UHPC consists of secondary reinforcement in the form of steel or polymeric fibers, which enable UHPC to exhibit tension hardening behavior and tension ductility previously ignored in conventional concrete mixes. Previous research has focused on applications in the transportation and bridge design industries; however, applications in buildings and other heavy …

Alternativas Para Mitigar La Susceptibilidad A La Socavación E Inestabilidad Del Talud De La Vía Medina - Santa María Por La Acción Del Río Gazaunta, Katherine Johana Bejarano Novoa

Ingeniería Civil

Los eventos de avenidas torrenciales del río Gazaunta causadas por las fuertes precipitaciones sumado a pertenecer a una zona de transición han generado procesos de socavación y erosión en la vía Medina- Santa María. Con este proyecto se pretende analizar la susceptibilidad a la socavación e inestabilidad del talud de la vía Medina - Santa María entre el K7+400 y K8+200 por incidencia del río Gazaunta implementando cinco (5) fases metodológicas que consisten en la recopilación y procesamiento de información, estimación de caudales (estudio hidrológico y modelación en HEC-HMS), caracterización hidráulica del río Gazaunta (Uso del software HEC-RAS). caracterización de …

Investigating The Mechanical Properties Of Frozen Soil Using Non-Destructive Seismic Wave Measurements, Sean Mach

Williams Honors College, Honors Research Projects

This proposed project will be dealing with investigating the mechanical properties of soil under frozen conditions. This will be done by an innovative non-destructive technology measuring the propagation of seismic waves through the frozen soils from multiple piezoelectric sensors. For the duration of this research, a freezing cell must be constructed to carry out the experimental testing. Multiple levels of saturation will be tested under the given freezing conditions. This should highlight the effect that the level of saturation will have on the propagation of seismic waves throughout the soil. Piezo-electric sensors will be placed in each layer of soil …

Comparative Analysis Of Bridge Abutment Types, David Fell

Williams Honors College, Honors Research Projects

This project was developed to serve as a brief overview of design practices and considerations in the selection of highway bridge abutment types. This involved a review of literature in the form of reviewing national design guides and department of transportation (DOT) requirements from both US DOTs and international DOTs. The abutment types covered in this research included conventional reinforced concrete abutments with bearings, integral abutments, and semi-integral abutments. This research focused solely on highway bridge abutments, particularly on Ohio Department of Transportation design requirements due to their extensive use of semi-integral abutments. Superstructure elements and geometric requirements are primary …

Additive Manufacturing Of Soil Using Bio-Cementation, Christina Childress

Graduate Theses and Dissertations

Microbially Induced Calcite Precipitation (MICP) is an emerging soil treatment technique that is proven to increase strength, decrease erosion, reduce liquefaction risk, enhance slope stability, decrease compressibility, decrease swelling potential, and overall create a more competent soil. The benefits and applications of MICP are broad, and this research seeks to broaden them further by developing a single-phase additive manufacturing application with no treatment time delay. This is done by analyzing layering behaviors of five USCS soil classifications (100 % Ottawa sand, sand clay mixtures, and 100% lean clay) which provides insight into process variables such as the solution volume and …

Epoxy Glass Fiber Reinforced Plastic Dowel Splice For Prestressed Precast Concrete Pile, Saman Farhangdoust

FIU Electronic Theses and Dissertations

Due to limitations in operation, shipping difficulties, and unforeseen soil conditions, it often happens that splicing of precast-prestressed concrete pile (PPCP) segments has to be performed at the construction site to achieve longer lengths. In order to splice PPCPs, Glass fiber reinforced polymer (GFRP), Carbon Fiber Reinforced Polymer (CFRP), and Stainless Steel (SS) dowels can be used as corrosion-resistant bars. In addition to their durability and superb mechanical performance, GFRP bars show cost advantage when compared to other corrosion-resistant materials. The objective of this study is to investigate the flexural behavior and effectiveness of the GFRP dowel and compare its …