Civil Engineering Commons^™

An Assessment Of The Accuracy Of The Euler-Bernoulli Beam Theory For Calculating Strain And Deflection In Composite Sandwich Beams, Qhinhon D. Ho

University of New Orleans Theses and Dissertations

This study focuses on assessing the accuracy of the Euler-Bernoulli beam theory as computational bases to calculate strain and deflection of composite sandwich beam subjected to three-point and four-point bending. Two groups of composite sandwich beams tests results will be used for comparison purposes. Mechanical properties for the laminated skin are provided by researchers from University of Mississippi (Ellen Lackey et al., 2000). Mechanical properties for the balsa wood core are provided by Alcan Baltek Corporation. Appropriate material properties and test geometries are then used in the Euler-Bernoulli-based algorithm in order to generate analytical data for comparison to experimental data …

Numerical And Experimental Investigations Of Dam And Levee Failure, Ezzat Youssef Elhassan Mohamed Elalfy

Theses and Dissertations

Both numerical and experimental investigations are conducted to study the failure of earthen dams and levees. Boussinesq equations describing one-dimensional unsteady flow including non-hydrostatic pressure distribution are solved numerically along with Exner equation for the sediment mass conservation to include the effects of the streamline curvature on the failure of non-cohesive earthen embankments. In addition, the effects of the steep bottom slope on the flow variables during the failure are studied by solving the Saint- Venant equations modified for steep bed slope along with the Exner equation to simulate non-cohesive earthen embankment failure due to overtopping. The Boussinesq equations are …

Assessment Of Classifiers For Potential Voice-Enabled Transportation Apps, Md Majbah Uddin

Theses and Dissertations

Transportation apps are playing a positive role for today’s technology-driven users. They provide users with a convenient and flexible tool to access transportation data and services, as well as collect and manage data. In many of these apps, such as Google Maps, their operations rely on the effectiveness of the voice recognition system. For the existing and new apps to be truly effective, the built-in voice recognition system needs to be robust (i.e., being able to recognize words spoken in different pitch and tone). The goal of this study is to assess three post-processing classifiers (i.e., bag-of-sentences, support vector machine, …

Confluence Of Density Currents Over An Erodible Bed, Hassan Ismail

Theses and Dissertations

Results from laboratory experiments on conservative density current confluence are reported. Hydraulic characteristics and morphodynamic consequences of the confluence of two continuous release density currents in a horizontal, 45 degree asymmetrical junction are examined and compared to those of terrestrial river junctions. It was observed that density current confluence is markedly different than those in river junctions primarily due to the ease of the dense fluid to convect into the ambient fluid in the junction zone. Upward convection in the junction resulted in low horizontal velocity and shear stresses on the bed of the junction zone, followed by re-plunging to …

Slope Stability Enhancement Of An Upstream Tailings Dam: Laboratory Testing And Numerical Modelling, Yazeed A. Alsharedah

Electronic Thesis and Dissertation Repository

Mine tailings are the byproduct of mining activities, which need to be disposed of once the ore is extracted. They can be disposed of in either dry or wet forms. The latter is most common with the tailings being disposed of in the form of slurry inside retention structures. The retention structure may be a natural, manmade, or built dam, which is the case in most of nowadays mining locations. In this thesis, improving the stability of an upstream tailings dam using soil additives is investigated. The experimental phase of this study involved laboratory tests conducted to characterize mine tailings …

Site Development At The Corner Of Drake And Stadium, Ahmad Sear Rahimi

Honors Theses

This report presents the site layout alternatives for the development located at the corner of Drake and Stadium in Kalamazoo, Michigan. In the report four different layouts are suggested and followed by best management practices for grading and earthwork plans, porous asphalt pavement design, storm water retention design for the proposed site, and storm sewer pipe design. The redesign of the Costco Development Site aims to maximize efficiency of the development area through the warehouse and gas station location, parking lot layout, and trucking routes. Grading design is developed based on the existing site conditions before construction took place. The …

The Aerodynamic And Dynamic Loading Of A Slender Structure By An Impacting Tornado-Like Vortex: The Influence Of Relative Vortex-To-Structure Size On Structural Loading, Matthew Nicholas Strasser

Graduate Theses and Dissertations

Structural loading produced by an impacting vortex is a hazardous phenomenon that is encountered in numerous applications ranging from the destruction of residences by tornados to the chopping of tip vortices by rotors. Adequate design of structures to resist vortex-induced structural loading necessitates study of the phenomenon that control the structural loading produced by an impacting vortex. This body of work extends the current knowledge base of vortex-structure interaction by evaluating the influence of the relative vortex-to-structure size on the structural loading that the vortex produces. A computer model is utilized to directly simulate the two-dimensional impact of an impinging …

Application Of Polyacrylamide-Based Floc Logs For Turbidity Control At Highway Construction Sites, Kien Ngo

Graduate Theses and Dissertations

Runoff waters generated on highway construction sites can have turbidities in excess of the proposed EPA regulatory standard of 280 NTU due to large areas of exposed soil. The objective of this research was to develop best management practices (BMPs) for the use of anionic polyacrylamide (PAM) based Floc Logs, for turbidity control. Five commercially available types of PAM-based Floc Logs were evaluated in jar tests, using soil excavated from Cato Springs Research Center (CSRC, Fayetteville AR) and six types of clay from the Clay Minerals Society (Chantilly, VA). These results show that no single Floc Log type was suitable …

Robust Model Development For Evaluation Of Existing Structures, Saurabh Prabhu

All Dissertations

In the context of scientific computing, validation aims to determine the worthiness of a model in supporting critical decision making. This determination must occur given the imperfections in the mathematical representation resulting from the unavoidable idealizations of physics phenomena. Uncertainty in parameter values furthers the validation problems due to the inevitable lack of information about material properties, boundary conditions, loads, etc. which must be taken into account in making predictions about structural response. The determination of worthiness then becomes assessing whether an unavoidably imperfect mathematical model, subjected to poorly known input parameters, can predict sufficiently well in its intended purpose. …

Hydrodynamic Modeling Of The Green Bay Of Lake Michigan Using The Environmental Fluid Dynamics Code, Paula Estefania Cedillo

Theses and Dissertations

In this project we created a hydrodynamic model of the Lower Green Bay of Lake Michigan in Wisconsin, United States using the Visual Environmental Fluid Dynamics Code (EFDC). The model includes four tributary rivers to Lower Green Bay as well as the open boundary flow conditions at Chambers Island. This case study is used to: 1) compare the results obtained with a previous study of Lower Green Bay to validate the creation of the model 2) examine the hydrodynamics of the bay, and 3) create a framework for future studies at Lower Green Bay. The Geographic Information used to build …

Feasibility Of Underground Freight Transportation (Uft) In Texas, Seyedeh Hosna Mousavipour

Civil Engineering Theses

The U.S. economy is expected to double in size over the next 30 years. Truck and rail freight traffic is expected to increase by approximately 45 percent. Air freight is expected to triple in response to demand for the rapid movement of high-value merchandise, while multimodal shipments will likely double. Texas with a gross state product (GSP) of $1.4 trillion dollars is the second largest economy in the U.S. Its size and population, central location, Gulf coastline, and energy resources require a reliable freight transportation system to facilitate further growth. This thesis focuses on the feasibility of Underground Freight Transportation …

Experimental Study On Seismic Performance Of Reinforced Concrete Coupling Beams And Rectangular Squat Walls With Innovative Reinforcement Configurations, Poorya Hajyalikhani

Civil Engineering Theses

Reinforced concrete core walls, coupled by diagonally reinforced coupling beams (DCBs), are a very efficient seismic force resisting system for medium- to high-rise buildings. The diagonal reinforcing bars in DCBs are most effective when the beam has a span-to-depth ratio, ln/h, less than 2. Modern construction, due to architectural requirements, typically requires span-to-depth ratios between 2.4 to 4, which leads to a very shallow angle of inclination of the diagonal reinforcement (generally between 10 to 20 degrees). The lower angles of inclination, combined with the detailing requirements specified in ACI 318, results in reinforcement congestion as well as design and …

Slope Stabilization And Performance Monitoring Of I-35 And Sh-183 Slopes Using Recycled Plastic Pins, Sandip Tamrakar

Civil Engineering Theses

The United States earth retaining structure market exceeds 170 million square feet annually and there are over 50 different retaining systems to select from which are unique in design and construction. Depending on the type of retaining structure, unit costs vary from less than $20 to in excess of $250 per square foot. Selecting the technically appropriate and cost-effective system is often critical to project cost and schedule. The Recycled Plastic Pin (RPP) has potential to be utilized as a sustainable and cost effective option to stabilize the surficial slope failure. RPP have been successfully used in Missouri, Iowa and …

Landfill Volume Gain From The Diversion Of Construction And Demolition Waste, Aayush Raj Tiwary

Civil Engineering Theses

Construction and Demolition (C&D) waste is one of the major components of the solid waste and is defined as a waste stream resulting from the construction, renovation and demolition of structures such as buildings, roads, and bridges. The amount of C&D waste has been in an upsurge with rapid growth in construction works and is expected to grow even more. As such, the effective waste management for C&D disposal has been a global issue owing to the increasing construction works worldwide. Although landfill disposal of C&D waste is not the preferred method of the C&D waste management, a significant portion …

Estimation Of Rebar Corrosion In Concrete Using Ground Penetrating Radar, Rakesh Krishnarajapete Raju

Civil Engineering Theses

The purpose of this research was to quantitatively relate the amount of rebar corrosion in concrete with the amplitude of electromagnetic waves generated from Ground penetrating radar (GPR). Many studies have been undertaken on qualitative measurement of corrosion, but there are very few studies regarding estimation of rebar corrosion quantitatively. This experiment involved the use of accelerated corrosion by impressed current technique to corrode the rebar inside the concrete and GPR to determine the extent of corrosion, while making a comparison with a stainless steel bar which was used as a cathode to create a galvanic cell action. Rebars were …

Improving The Rainfall And Flood Frequency Analyses Using Stochastic Storm Transposition Method, Morteza Kiani

Civil Engineering Theses

Reproduction and realization of historical rainfall events provides foundations for flood and rainfall frequency analyses and the advancement of meteorological studies. Stochastic storm transposition (SST) is a method for such a purpose and enables us to perform frequency analyses by transposing observed historical storm events over any given watershed. The goal of this study is to stochastically examine the impacts of extreme events on all locations in a homogeneity zone. Storms with the same probability of occurrence on a defined homogenous neighborhood will generate various impacts due to spatial and temporal variations of the storms. Transposing storms occurring in the …

Merging Radar-Only Qpe And Rain Gauge Data Via Conditional Bias-Penalized Optimal Estimation, Beomgeun Kim

Civil Engineering Theses

A new technique for merging radar precipitation estimates and rain gauge data is developed and evaluated to improve multisensor quantitative precipitation estimation (QPE). Various types of linear and nonlinear techniques have been used to combine rain gauge and radar data. Linear cokriging and its variants, for example, may be considered as the best linear unbiased estimators which minimize the error variance in the unconditional sense. They are, however, subject to conditional biases (CB) that may be unacceptably large for estimation of heavy-to-extreme precipitation. In this work, I develop, apply, and evaluate conditional bias-penalized cokriging (CBPCK) for spatial estimation of precipitation …

Characterization And Comparison Of Fresh And Landfilled Solid Waste, Kavya Koganti

Civil Engineering Theses

The understanding of the characteristics of Municipal Solid Waste (MSW) is very important in planning, designing and operating and/or upgrading the landfill operation system. It is well anticipated that the fresh MSW will be different from the landfilled MSW due to degradation. However, there is no systematic study on the comparison of physical properties of fresh and landfilled waste from bioreactor and/or enhanced leachate recirculated (ELR) landfills. The most important MSW properties to be considered while planning a landfill system are physical composition, moisture content, unit weight and volatile solids content. These properties are of particular interest especially when an …

Medium-Range Ensemble Precipitation And Streamflow Forecasting For The Upper Trinity River Basin In Texas Via The Nws Hydrologic Ensemble Forecast Service, Hossein Sadeghi

Civil Engineering Theses

Compared to forecasts of short-term precipitation accumulations (daily or shorter) at lead times larger than a few days, those of longer-term accumulations (3-daily or longer) are significantly more skillful owing to the larger temporal scale of aggregation. If one can utilize this skill present in medium-range precipitation forecast in hydrologic prediction, it is very likely that the lead time of hydrologic forecasts, in particular, of streamflow and soil moisture may be extended. Though forecasts of longer-term accumulations of precipitation are more skillful than those of shorter-term accumulations, precipitation forecasts in general are too uncertain to be used as deterministic, or …

Thermo-Hydro-Mechanical Behavior Of Unsaturated Clayey Soils Via Thermo/Suction-Controlled Ring Shear Testing, Jairo Edmundo Yepes Heredia

Civil Engineering Dissertations

There is a lot of geotechnical infrastructure made of compacted soil, or resting on unsaturated ground, which involves a wide range of deformations. Calculation of foundation settlement, for instance, requires a good estimation of soil stiffness at relatively small strains. Analysis of natural and engineered earth slopes, embankments, and soil bearing capacity, on the other hand, requires good estimations of shear strength, from peak to residual. Besides, despite the critical importance of the thermo-mechanical behavior of unsaturated soils in many geotechnical applications, the effect of relatively high temperature on shear strength and stiffness properties of unsaturated soils is not yet …

Behavior Of Buried Composite Arch Bridges, Harold J. Walton

Electronic Theses and Dissertations

This dissertation presents experimental results and numerical analysis for short-span buried composite arch bridges whose main structural members are concrete-filled fiber reinforced polymer (FRP) tube arches (CFFTs). This investigation focuses on soil- structure interaction of the bridge system to expand understanding beyond isolated arch performance. Soil plays several roles: weight on the structure, restraining arch movement, and dissipating surficial truck loads.

Investigation focused on experimental and numerical analysis of subscale bridge systems. Four bridge systems were constructed with two different span-to-rise ratios (5:1 and 2.67:1) and two different materials (linear-elastic steel and CFFT). Tested systems were half-scaled from commercial bridge …

Experimental Evaluation Of Beneficial Use Of Lake Michigan Dredged Materials In Flyash Based Geopolymer Concrete, Sara Dashti

Theses and Dissertations

Dredging harbors and rivers are necessary to maintain the appropriate water depth for navigation. However the disposal facilities for storing dredged materials around the U.S. Great Lakes are at or near their capacities and finding beneficial uses for these materials is a major concern. On the other hand, carbon emission and global warming have become the greatest environmental issues during the last decade. Cement manufacturing is a major contributor to CO2 release into the atmosphere. The objective of this study was to develop a low-cost, environment-friendly geopolymer concrete paste with dredged materials as a substantial mix ingredient. Geopolymer concrete does …

Comparative Analysis Of Buckling-Restrained Braced Frames In Eccentric Configuration (Brbf-Es) And Eccentrically Braced Frames (Ebfs), Peter T. Vayda

Civil Engineering Undergraduate Honors Theses

Continuing on the findings of “Using Buckling-Restrained Braced Frames in Eccentric Configuration,” by Dr. Gary S. Prinz, P.E., which determined that, from a performance standpoint, BRBF-Es could be a viable alternative for EBFs. A comparative analysis was conducted on the design procedures and initial cost estimates of BRBF-Es and EBFs. Upon designing four 12-Story buildings (two BRBF-Es and two EBFs), it was determined that BRBF-Es were easier to design due to the statically determinant system. The initial costs estimates of BRBF-Es; however, ranged upwards of 30% more cost than EBFs. Therefore, the initial investment of more intensive structural engineering design …

Bankfull Geomorphic Relationships And Hec-Ras Assessment In Small Catchments Of The Cumberland Plateau Ecoregion, Ryan Lee Hodges

Masters Theses

There is a great need for state governments to have effective watershed restoration and mitigation efforts to return degraded ecosystems to a stable, healthy condition. Given the growing investment in stream restoration efforts, there is an urgent need for tools to assess and improve the effectiveness of restoration efforts at local, state, and nationwide scales. In 2000 there was less than ten stream restoration permits provided by the state of Tennessee and has increased each year with almost forty permits issued in 2013. To better achieve successful stream restoration, appropriate channel designs must be used that reflect the hydraulic conditions …

Enhanced Shrinkage Characterization Of Clayey Soils, Raju Acharya

Civil Engineering Dissertations

Surficial slope failure is a common problem experienced by most of the compacted earth dams in Texas and several other southern states in USA as a result of desiccation or shrinkage induced cracking of the surficial soils. Cracking of the soil occurs when the tensile stress exceeds the tensile strength during drying process. Tensile stress increases with an increase in shrinkage strain and thus soil chemical admixtures can reduce the tensile stress by reducing the shrinkage potential of soil. Inclusion of such admixtures invariably affects the tensile strength. Yet there are not many test methods that could be utilized for …

Improving Water Quality Forecasting Using Data Assimilation, Hamideh Riazi

Civil Engineering Dissertations

Population growth increases agricultural, industrial and human activities which threaten the quality of water resources, especially water supply sources such as lakes and reservoirs. In potentially high-impact situations such as algal blooms, active measures such as controlled release from reservoirs may be necessary. To minimize release while meeting the water quality requirements, accurate short-range water quality forecast is necessary. Because watershed water quality models have a large number of state variables most of which are never observed, their initial conditions (IC) are subject to large uncertainties which may propagate into large forecast errors. In this research, a data assimilation (DA) …

Comprehensive Neural Network Forecasting System For Ground Level Ozone In Multiple Regions, Gautam Raghavendra Eapi

Civil Engineering Dissertations

A comprehensive neural network daily maximum 8 hour-ozone forecasting model was developed based on five years of data (2010-2014) collected from 50 monitoring sites from the Dallas Fort Worth, Houston-Galveston-Brazoria, Los Angeles, San Joaquin and San Diego regions. This work represents the first neural network developed to forecast ozone in multiple regions, as well as multiple sites in the same region. Previous studies have developed separate neural network models to forecast ozone at each location. Two stages of feature selection were applied to reduce input vector dimension and redundancy. These are Piecewise Linear Orthonormal Floating Search (PLOFS), and Karhunen - …

Operational Analysis Of Traditional Access Management Strategies & Demand-Responsive Access Control On Arterials, Joshua Mitchell

All Theses

Arterials are typically characterized by closely-spaced signalized intersections, high driveway density, and high traffic volumes. These characteristics contribute to congestion, as well as crashes. Access management strategies can address both operational and safety issues on urban arterials. This research focuses on the operational impacts of access management with two objectives: (1) quantify the impacts of ‘traditional’ access management strategies and (2) quantify the impacts of demand-responsive access control. To satisfy Objective 1, four traditional access management strategies were tested – (i) access spacing, (ii) corner clearance, (iii) access restriction, and (iv) raised median implementation. These were analyzed in four respective …

Design And Analysis Of Foundation For Onshore Tall Wind Turbines, Shweta Shrestha

All Theses

Wind turbines play a vital role in producing sustainable and clean energy to fulfill the growing energy needs. Energy generated from wind turbines being more sustainable and cost effective, many countries have taken a major step to develop wind turbines with large capacity. There has been a significant reduction in the levelized cost of energy (LCOE) since the 1980’s from the development of larger wind farms and from consistent performance improvements of wind turbine components. The power generation capacity of wind turbines has increased significantly over the years with the use of taller towers. When the tower height increases, the …

Practical Robust Geotechnical Design- Methodology And Applications, Sara Khoshnevisan

All Dissertations

This dissertation advances the robust geotechnical design methodology by offering improvements, which makes it more efficient and practical for the design of geotechnical systems. Robust geotechnical design (RGD) methodology seeks an optimal design, which is insensitive to, or robust against, the variation in the uncertain input parameters (called “noise factors”) by only adjusting the easy to control parameters (called “design parameters”). The main goal of robust design is to consider safety, cost and robustness simultaneously. Because the cost and the robustness are conflicting objectives, the multi-objective optimization that considers these two objectives while enforcing the safety constraint yields not a …