Civil and Environmental Engineering Commons^™

Comparison Of Safety Performance By Design Types At Freeway Diverge Areas And Exit Ramp Sections, Hongyun Chen

USF Tampa Graduate Theses and Dissertations

The primary objective of the study is to evaluate the safety performance of different freeway exit types used in current practical designs. More specific, the research objectives include the following two parts: 1) to compare the safety performance of different design types at freeway diverge areas and exit ramp sections; and 2) to identify the impact factors contributing to the crashes happening at these two specific segments.

The study area includes four subjects, the freeway widely-spaced diverge areas; the freeway closely-spaced diverge areas; the left-side off-ramps and the exit ramp sections. For the freeway diverge areas, design types were defined …

A Multicriteria Based Quantitative Framework For Assessing Sustainability Of Pile Foundations, Aditi Misra

Master's Theses

ABSTRACT

Civil Engineering is the major instrument of anthropocentric development over centuries through ever expanding infrastructure, cities and facilities. Civil engineering processes are both resource and fuel intensive. The building industry alone, during the construction stage, uses about 30-40% of the total resources used in the industrialized countries. There is a growing consensus that delivering a sustainable built environment starts with incorporating sustainability thoughts at the planning and design stages of a project. Geotechnical engineering is most resource intensive although this intensive consumption of energy goes unnoticed mainly because of the indirect nature of the energy used in the …

Effects Of Warm-Mix Asphalt Additives On Asphalt Mixture Characteristics And Pavement Performance, Jun Zhang

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

The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera synthetic zeolite) were evaluated. For a more realistic evaluation of the WMA approaches, trial pavement sections of the WMA mixtures and their HMA counterparts were implemented in Antelope County, Nebraska. More than one ton of field-mixed loose mixtures were collected at the time of paving and were transported to the NDOR and UNL laboratories to conduct comprehensive laboratory evaluations and pavement performance predictions of the …

The Use Of Building Information Modeling In Generating Hard Bid Estimates, Peter Samuel Jensen

Theses and Dissertations

Building Information Modeling has provided many benefits to the architectural, engineering, construction and facilities management communities. Many studies have been done to validate the asserted benefits, including benefits to the field of estimating. The studies on estimating are currently limited to the realm of conceptual estimates, and have only treated detailed estimates in the abstract. The purpose of this study was to determine how BIM was being used by companies in a hard bid, or detailed estimate scenario. The research team used the Deseret Towers housing project at Brigham Young University as the basis for the research. A building information …

Fotogrametría Terrestre Aplicada A Modelos Físicos Del Laboratorio De Procesos Geotécnicos, Marinela Pinzón Muñóz

Ingeniería Civil

No abstract provided.

Wake Dynamics And Passive Flow Control Of A Blunt Trailing Edge Profiled Body, Lakshmana Sampat Doddipatla

Electronic Thesis and Dissertation Repository

Wake flows behind two-dimensional bodies are dominated mainly by two types of coherent structures, namely, the Karman Benard vortices and the streamwise vortices, also referred to as rolls and ribs respectively. The three-dimensional wake instabilities lead to distinct instability modes (mode-A, mode-B and mode-C or mode S) depending on the flow Reynolds number and geometric shape. The present investigation explores the mechanism by which the flow transitions take place to three-dimensionality in the near wake of a profiled leading edge and blunt trailing edge body. Experiments consisting of a combination of Planar Laser Induced Fluorescence visualizations and Particle Image Velocimetry …

Determining The Cyclic Strength Of Geomaterials Under Low Frequency Cyclic Loading With Acoustic Emission, Helsin Wang, Ta-Peng Chang, Ju-Jiang Hung

Journal of Marine Science and Technology

Acoustic emission is traditionally regarded as an explicit measurable index for microcracking in geomaterials. An accelerative cracking point is first introduced based on the different characteristics of acoustic emission at stable fracture propagation stage. Accelerative cracking point is located between the fracture initiation strength and critical energy release point, a point causing a fatal uncontrolled fracture in materials. Microcracking dominates the real mechanical characteristics in the materials, not reflected on the conventional mechanical experimental results as the stress level beyond the accelerative cracking point at the stable fracture propagation stage. At this stage, non-stress-controlled fracture in materials could arise as …

The Application Of E-Technology For Marine Information Service, Lien-Kwei Chien, Tsung-Shen Feng, Chieh-Cheng Yen, Beng-Chun Lee, Heng-Wen Chang

Journal of Marine Science and Technology

The purpose of this study is to establish the multi-function querying system by applying e-technology in marine data. Subjects tendency technology is new concept in system designing process of this study which originate from simulation language that was replace the structural technology. We also investigate the statistical characteristics of ocean waves and surges over Taiwan waters by cluster and return period analysis. Marine drifter track analysis and search area determination system were also analysis and import to GIS querying system. In order to make the locations of the near shore ships and sailing data could be easily convey through wireless …

Response Analysis Of Concrete Piles Subjected To Lateral Impact, Helsin Wang, Ta-Peng Chang, Jin-Jun Wang

Journal of Marine Science and Technology

One-dimensional wave theory is assumed to interpret longitudinal waves impulse response or impact echo testing results in concrete piles. Transient flexural waves tests are alternatively introduced to evaluate piles where the tops are inaccessible for conventional longitudinal wave testing. The resulting interpretation for flexural waves based on one-dimensional wave theory is improper due to various velocities at low frequencies. In this research, treating a pile as a waveguide, three-dimensional wave theory provides the dispersion relation between phase flexural velocity and frequency. Using the resonance solutions and first-mode flexural wave curve is a simple and efficient method to find the resonant …

Investigation On Vibration Energy Flow Characteristics In Coupled Plates By Visualizaiton Techniques, Kai Li, Sheng Li, De-You Zhao

Journal of Marine Science and Technology

The transmission and distribution of vibration energy flow in coupled plates are studied by the vibration intensity method together with visualization technique. Formulations for vibration intensity calculations and streamline representation, and the equations for energy flow are presented. The intensity vector, streamline map and energy distribution of coupled plates subject to a point force excitation are calculated and visualized to predict vibration energy transmission. The vibrational energy flows are very complex and dependent on the excitation frequencies, junction forms and boundaries. The energy sources, sinks, transmission paths and vortex fields are clearly shown with visualization technique. It is shown that …

Stability Assessment For The Undersea Gas Pipeline, Wen-Chien Tseng, Lien-Kwei Chien, Sheng-Tse Chuang, Pei-Chi Tsai, Ya-Ting Hsu, Ting-Ting Lu, Chu-Kuan Lin

Journal of Marine Science and Technology

In general, the activities of harbour district, coastal construction and re-transportation of tide and current are all possible to influence the stability of research area and sediment environment in nearshore area. It indicates that status of deposit property of seabed and variability of sediment environment are important factors to stability and safety for the path of undersea gas pipeline. An assessment procedure and approach for the prediction of the wave-induced and earthquake-induced liquefaction potential and erosion potential are proposed for marine engineering practice. The soil sample of this study is obtained from deposit zone of gas pipeline of seabed in …

A Time-Domain Analysis Of Wave Force On Small-Scale Cylinders Of Offshore Structures, Bao-Lei Geng, Bin Teng, De-Zhi Ning

Journal of Marine Science and Technology

To get the accurate wave loads on the small-scale cylinders on the platforms, not only the incident wave but also the diffraction and radiation wave should be considered. By taking the wave diffraction from a fixed large-scale cylinder as an example, wave loads on small-diameter cylinders in the diffraction wave field are calculated by Morison formula in this paper. A time-domain numerical model on wave diffraction from large-scale structures is developed with a higher-order boundary element method (HOBEM). Then the velocity and acceleration of any water particle in the fluid domain can be produced from the solved diffraction potential. Results …

Cooperation-Competition Model Of Transportation Construction Project From The Viewpoint Of Budget Allocation, Maw-Cherng Lin, Edward Ming-Yang Wu, Junn-Yuan Teng, Wen-Chih Huang

Journal of Marine Science and Technology

Department of Marine Engineering, National Taiwan Ocean University, Keelung 202, Taiwan.

The Effects Of Electricity Pring On Phev Competitiveness, Shisheng Huang, Bri-Mathias S. Hodge, Farzad Taheripour, Joseph F. Pekny, Gintaras V. Reklaitis, Wallace E. Tyner

PPRI Digital Library

Plug-in Hybrid Electric Vehicles (PHEVs) will soon start to be introduced into the transportation sector, thereby raising a host of issues related to their use, adoption and effects on the electricity sector. Their introduction has the potential to significantly reduce carbon emissions from the transportation sector, which has led to government policies aimed at easing their introduction. If their wide-spread adoption is set as a target it is imperative to consider the effects of existing policies that may increase or decrease their adoption rate. In this study, we present a micro level electricity demand model that can gauge the effects …

Hydraulic Conductivity Of Cement-Treated Soils And Aggregates After Freezing, Michael Scott Shea

Theses and Dissertations

Improvements in the strength and durability of frost-susceptible soils and aggregates can be achieved through chemical stabilization using portland cement, where the efficacy of cement stabilization for improving durability depends on the degree to which hydraulic conductivity is reduced. Hydraulic conductivity is commonly estimated from basic soil properties using Moulton's empirical equation. However, the hydraulic conductivity estimation does not consider the detrimental effects of freezing or the benefits of cement stabilization. The purpose of this research was to derive new equations relating hydraulic conductivity after freezing to specific material properties of cement-treated soils and aggregates stabilized with different concentrations of …

Two-Zone Transient Storage Modeling Using Temperature And Solute Data With Multiobjective Calibration: 1. Temperature, Bethany T. Neilson, S. C. Chapra, David King Stevens, Christina J. Bandaragoda

Civil and Environmental Engineering Faculty Publications

This paper presents the formulation and calibration of the temperature portion of a two-zone temperature and solute (TZTS) model which separates transient storage into surface (STS) and subsurface transient storage (HTS) zones. The inclusion of temperature required the TZTS model formulation to differ somewhat from past transient storage models in order to accommodate terms associated with heat transfer. These include surface heat fluxes in the main channel (MC) and STS, heat and mass exchange between the STS and MC, heat and mass exchange between the HTS and MC, and heat exchange due to bed and deeper ground conduction. To estimate …

Two-Zone Transient Storage Modeling Using Temperature And Solute Data With Multi-Objective Calibration: 2. Temperature And Solute, Bethany T. Neilson, David King Stevens, S. C. Chapra, Christina J. Bandaragoda

Civil and Environmental Engineering Faculty Publications

This paper presents the multiobjective calibration results for temperature and solutefrom a two‐zone temperature and solute (TZTS) model which separates transient storageinto surface (STS) and subsurface (HTS) transient storage components. This modelcontains terms associated with surface heat fluxes in the main channel (MC) and STS, heatand mass exchange between the STS and MC, heat and mass exchange between the HTSand MC, and heat exchange due to bed and deeper ground conduction. To estimate theadditional parameters associated with a multiple‐zone model, a data collection effort wasconducted to provide temperature time series and solute tracer curves representingthe movement of heat and/or solute …

The Effect Of Intellidrive On The Efficiency Of Highway Transportation Systems, Mohammad Nekoui, Hossein Pishro-Nik, Daiheng Ni

Daiheng Ni

Recently, the IntelliDrive initiative has been proposed by the US Department of Transportation (USDOT) to enhance on-road safety and efficiency. In this study, we provide a mathematical framework which predicts the effect of such technologies on the efficiency of multilane highway systems prior to their real-life deployment. Our study shall encompass mixed traffic conditions in which a variety of assisted, automated and unequipped vehicles coexist. We show that intervehicular communications improves the flow of vehicles by reducing the perception-reaction (P-R) times of drivers and, in some cases, allowing for more efficient lane-changing operations. As we shall see, unlike the latter, …

Soil Behavior Under Blast Loading, Jichong An

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

Understanding the behavior of soil under blast loading is very important to engineers in mining, tunneling, and military construction. Due to the very complex structure of a soil mass it is very difficult to describe its constitutive relation, especially when it has different water contents and it is under blast loading conditions. New protective system designs subjected to blast loading need to be proved its validation prior to predict effect of explosive before implementation. Full-scale, buried explosive tests are costly. Finite element simulations play a significant role in the design of protective systems, for example a bottom platform of lightweight …

A Generalized Non-Parametric Approach For Uncertainty Evaluation In Travel Time Prediction Models, Bhaven Naik

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

A core component within Advanced Traveler Information Systems is travel time information because it is easily understood and perceived by travelers. However, the suggested travel time information should be based not only on historical and real-time conditions, but also on forecasted or “unknown” future conditions.

Existing research has focused primarily on developing models that forecast point estimates of the mean travel time that are in close comparison to their respective field values. There has been limited research on any insight into the reliability or uncertainty margin that exists around the forecasted point estimate. As well, these researches have a limitation …

Embedded Radio Frequency Identification Device License Plates For Roadside Use In Nebraska, Dwight L. Mosby Jr

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

The transportation industry has many stakeholders with different needs that work with advanced technologies. Radio Frequency Identification (RFID) is an emerging technology that is used to track inventory and it holds promise for the transportation industry. This research identifies how to evaluate transportation stakeholder requirements for RFID technologies using a tool described as the House of Quality (HOQ). This research investigates RFID’s ability to work in license plates and may provide infrastructure to support identifying RFID enabled commercial vehicles. This research considers variables that affect the performance of a RFID License Plate System that will use a scanner located at …

Modelación Física De Sumideros Laterales Tipo Ventana Para Vías Urbanas, Miguel Ángel Barragán Ochica

Ingeniería Civil

El proyecto comprende dos partes principales. La primera de carácter teórico, en la cual se hizo un análisis del estado del arte con respecto al estudio de los sumideros laterales tipo ventana y se realizaron salidas de campo con el fin de recopilar un inventario sobre las características principales de los sumideros estudiados en este proyecto. La segunda parte enmarca el trabajo de laboratorio, en el cual se construyó un modelo a escala de una vía urbana (Ver Imagen 1), y con este modelo se 6 realizaron mediciones del caudal resumido por los sumideros laterales bajo diversas condiciones. Entre las …

Collaborative Research: An Integrated Microstructure-Based Approach To Property Prediction For Cement-Based Materials, Eric N. Landis

University of Maine Office of Research Administration: Grant Reports

The project is a collaborative effort between the research groups at the University of Maine and the University of California, Davis. It represents a convergence of 3D micro-structural imaging with discrete element computational modeling to address the need for quantitative links between salient micro-structural properties and bulk material performance. High-resolution 3D images of material microstructure will be produced using x-ray microtomography (XMT). These images will be used to examine the micromechanical response of cement composites to mechanical loading and drying shrinkage. 3D deformation fields and internal crack distributions will be measured at selected loading stages and correlated with the spatial …

Tangerine Avenue Retrofitting Project, Ni-Bin Chang, Martin Wanielista

BMP Trains Research and Publications

No abstract provided.

Environmental Impacts To Stream Acidification And Brook Trout Populations In The Great Smoky Mountains National Park, Keil Jason Neff

Doctoral Dissertations

This research supports development of aquatic resource management strategies to address acid deposition in the Great Smoky Mountain National Park (GRSM) by 1) developing relationships between baseflow and stormflow chemical constituents and examining effects of elevation, area, geology, soil, and vegetation on stream chemistry; 2) evaluating physiological condition in brook trout in relation to changes in stream chemistry during stream acidification episodes, and 3) evaluating brook trout metrics with respect to stream chemistry, basin characteristics, and ecologically relevant hydrologic parameters. (1) Stream chemistry was monitored in eight GRSM streams considering basin area, site elevation, Anakeesta geology, soil, and vegetation. Following …

Durability And Fatigue Behavior Of Cip Concrete Connections For Accelerated Bridge Construction, Peng Zhu

Doctoral Dissertations

Continuous longitudinal and transverse U-bar joint connections between flanges of the decked bulb-Ts (DBTs) or between precast panels for accelerated bridge construction are investigated. The procedure for selecting durable closure pour (CP) materials for the connections is discussed firstly. The accelerated construction is quantified as two categories: overnight cure and 7-day cure of CP materials. Candidate materials are selected first based on literature review as well as tests of compressive strength and flow and workability. Then, performance criteria for selecting durable CP materials for both categories are developed based on durability tests of selected candidate materials. These durability tests include …

Investigating Wood Welding Parameters Using A Prototype Welding Machine, Timothy R. Melin

Master's Theses

Understanding how different processing variables influence wood welded bonds is vital if the technique will ever be used to create engineered lumber without using adhesives. A variation of vibration welding, wood welding uses pressure and friction to bond materials together. During welding, heat causes a softening in the wood, a naturally occurring composite material. This softening leads to fiber entanglement and a bond forms upon cooling.

The goal of this research was to investigate several processing aspects of the wood welding procedure. A prototype wood welding machine, designed and fabricated from the ground up, was used to investigate the effects …

The River Discontinuum: Applying Beaver Modifications To Baseline Conditions For Restoration Of Forested Headwaters, Denise Burchsted, Melinda Daniels, Robert Thorson, Jason Vokoun

Center for Integrative Geosciences

Billions of dollars are being spent in the United States to restore rivers to a desired, yet often unknown, reference condition. In lieu of a known reference, practitioners typically assume the paradigm of a connected watercourse. Geological and ecological processes, however, create patchy and discontinuous fluvial systems. One of these processes, dam building by North American beavers (Castor canadensis), generated discontinuities throughout precolonial river systems of northern North America. Under modern conditions, beaver dams create dynamic sequences of ponds and wet meadows among free-flowing segments. One beaver impoundment alone can exceed 1000 meters along the river, flood the valley laterally, …

Coordinating Production And Recycling Decisions With Stochastic Demand And Return, Jianmai Shi, Guoqing Zhang, Jichang Sha, Saman Hassanzadeh Amin

Mechanical, Automotive & Materials Engineering Publications

In this paper, the joint production and recycling problem is investigated for a hybrid manufacturing and remanufacturing system where brand-new products are produced in the manufacturing plant and recycled products are remanufactured into as-new products in the remanufacturing facility. Both the brand-new products and remanufactured products are used to satisfy customer demands. Returns of used products that are recycled from customers are assumed to be stochastic and nonlinearly price-dependent. A mathematical model is proposed to maximize the overall profit of the system through simultaneously optimizing the production and recycling decisions, subject to two capacity constraints — the manufacturing capacity and …

The Green, Blue And Grey Water Footprint Of Farm Animals And Animal Products. Volume 1: Main Report, Mesfin Mekonnen, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

The projected increase in the production and consumption of animal products is likely to put further pressure on the globe’s freshwater resources. The size and characteristics of the water footprint vary across animal types and production systems. The current study provides a comprehensive account of the global green, blue and grey water footprints of different sorts of farm animals and animal products, distinguishing between different production systems and considering the conditions in all countries of the world separately. The following animal categories were considered: beef cattle, dairy cattle, pig, sheep, goat, broiler chicken, layer chicken and horses. The study shows …