Civil Engineering Commons^™

High-Resolution Event-Based Data At Diamond Interchanges: Performance Measures And Optimizing Ring Displacement, Alexander M. Hainen, Amanda L. Stevens, Richard S. Freije, Christopher M. Day, James R. Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Performance Ranking Of Arterial Corridors Using Travel Time And Travel Time Reliability Metrics, Christopher M. Day, Stephen Remias, Howell Li, Michelle M. Mekker, Margaret L. Mcnamara, Ed Cox, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Design Considerations For A Rotating Retractable Stadium Roof, Charles S. Jenkins

Honors Theses

This thesis presents a novel type of retractable roof, adapting the pivot-based retraction system used in Miller Park to a stadium without a circular geometry. Existing stadiums with retractable roofs are reviewed, and lessons learned are used to present theoretical structural engineering design for a roof truss and recommendations for carriers. The presented concept likely requires light-weight structural systems and closely-spaced roof trusses to minimize loads on roof carriers. Actual mechanical designs of the roof carriers are quite complex as they must be able to roll in two directions and pivot about a third. The design herein is incomplete for …

Simulation Of Heat And Mass Transfer In Suns River Solar Distillation, Houman Azari

Open Access Theses & Dissertations

Many regions around the world have limited fresh water resources, and we need to desalinate brackish water resources for drinking and irrigation purposes. Most of the world is also facing energy challenges which encourages engineers and scientists to use renewable energy resources instead of hydrocarbon fuels. Arid regions such as the Middle East, many African countries, and the southwestern United States typically have abundant solar irradiance and brackish or saline water supplies. Solar-thermal desalination could be an important supply of fresh water in these regions.

The classic solar still is not efficient for providing large amounts of clean water for …

Studying The Parameters Involved With Modulus-Based Construction Quality Control For Compaction Of Unbound Pavement Layers, Mehran Mazari

Open Access Theses & Dissertations

Pavement performance is impacted by several factors such as the properties of the materials, combination of traffic and loading, structural capability, climate changes and construction process. Earthwork and unbound materials is an important part of pavement constructions since most of the distresses can be related to these geomaterials. Appropriate process control, proper processing of geomaterials, adequate amount of moisture and suitable compaction effort would ensure the required density and stiffness of the compacted pavement layer. The Nuclear Density Gauge (NDG) has been the primary means of Quality Control and Quality Acceptance (QC/QA) by State Highway Agencies (SHAs) and department of …

Using Fair Division Methods For Allocating Transportation Funds, Edith Montes

Open Access Theses & Dissertations

Current transportation funding allocation methods are very complex due to limited budgets and conflicting interests. In order to maintain an efficient infrastructure transportation system, agencies must balance the allocation of funds required either to increase the roadway capacity or to preserve the existing roads in service. Depending on the target objectives and specific constraints, the funding allocation process is approached using different methods. The funding allocation process is usually addressed using expert judgment which involves subjective criteria, weighted formulas with pre-established priorities, or a combination of both. However, formula-based funding allocation methods may lead to the public's disagreement if final …

Enhanced Finite Element Modeling Of The Thermo-Mechanical Responses Of Jointed Pcc Pavements Under Environmental And Traffic Loads, Mohammad Ali Zokaei Ashtiani

Open Access Theses & Dissertations

Jointed plain concrete pavements (JPCP) are the most commonly used type of rigid pavement systems and the accurate modeling of their thermo-mechanical responses is of primary importance in a mechanistic-empirical pavement design procedure. In JPCP, the temperature gradient and resulting slab shape play a crucial role in the magnitude of stresses and deflections caused by the superimposed traffic loads. Temperature gradients through the slab depth can produce thermal curling in slabs and can also produce slab expansion and contraction, which leads to the generation of frictional tractions between slabs and foundation. The prediction of these frictional tractions is complicated by …

Evaluation Of Ozone Trends In Southern Doña Ana County, New Mexico Thru Wind Rose Analysis And Use Of Noaa Hysplit Model, Maria Aurelia Sisneros

Open Access Theses & Dissertations

The objective of this study was to determine whether increasing ozone concentrations in 2012 and 2013 at the Santa Teresa air quality monitor in Doña Ana County, New Mexico were due to a local point source impacting this monitor only or part of a regional phenomenon that affects all the monitors within the Paso del Norte Region. In addition, the study focused on identifying local and regional/long-range source areas contributing transport ozone to the study area (southern Doña Ana County).

The study showed that increasing ozone levels were not unique to the Santa Teresa monitor due to the fact that …

Longitudinal Shear Resistance Of Composite Slabs Containing Crumb Rubber In Concrete Toppings, Niall Holmes, Kevin Dunne, John O'Donnell

Articles

This paper investigates the behaviour and longitudinal shear capacity of metal deck composite slabs with the inclusion of crumb rubber in the concrete toppings. The ability of the slabs to act compositely is governed by the shear interaction between the concrete topping and the profiled steel deck. Results here show that crumb rubber concrete (CRC) improve the overall shear bond capacity between the steel deck and topping following an experimental study on full scale loading tests in accordance with Eurocode 4. The results confirm that composite slabs incorporating crumb rubber had no effect on the longitudinal shear resistance with similar …

A Review Of The Hl-93 Bridge Traffic Load Model Using An Extensive Wim Database, Cathal Leahy, Eugene J. Obrien, Bernard Enright, Donya Hajializadeh

Articles

HL-93, the current bridge traffic load model used in the United States, is examined here. Weigh-in-motion from 17 sites in 16 states, and containing 74 million truck records, is used to assess the level of consistency in the characteristic load effects implied by the HL-93 model. The load effects of bending moment and shear force are considered on single-lane and two-lane same-direction slab and girder bridges with a range of spans. It is found that the ratio of WIM-implied to HL-93 load effect varies considerably from one load effect to another. An alternative model is proposed which achieves improvements in …

Civil Engineering Accreditation Document 2013 (Revised 2014), Georgia Southern University Libraries

Program Accreditation Reports (2013-2023)

This is the revised 2013 report for 2014.

Bs News January/February

Building Services Engineering

No abstract provided.

Increasing The Durability Of Piezoelectric Impact-Based Micro Wind Generator In Real Application, Hyun Jun Jung, Yooseob Song, Seong Kwang Hong, Chan Ho Yang, Sung Joo Hwang, Tae Hyun Sung

Civil Engineering Faculty Publications

The purpose of this study is to increase the durability of piezoelectric impact-based micro wind generator (PIMWG) in real application. Using new PIMWG design, numerical simulation, and experimental comparison analysis, we improved the durability of PIMWGs in real application. The experimental results show that the optimized PIMWG generated 2.4 mW (RMS value), and it did not crack within 40 h. In this study, we improved the durability of PIMWGs for real application.

Acoustic Properties Of Concrete Panels With Crumb Rubber As A Fine Aggregate Replacement, Niall Holmes, Alex Browne, Christopher Montague

Articles

This paper presents the acoustic performance of small scale crumb rubber concrete (CRC) panels in terms of the sound absorbance and insulation at low (63, 125, 250 & 500 Hz) and high (1000, 2000, 4000 and 5000 Hz) frequencies. Acoustic tests were conducted with differing levels of fine aggregate replacement with crumb rubber (7.5 and 15%) with four different grades following freezing and heating. Analysis of the workability, compressive strength and density are also presented. The results found that CRC performed well in terms of sound absorbance particularly with higher proportions (15% here) and grades of crumb rubber. As an …

Coupled Sediment Yield And Sediment Transport Model To Support Navigation Planning In Northeast Brazil, Calvin Trebor Creech

Wayne State University Dissertations

Deposition of sediment (shoaling) in commercial waterways is a major obstacle to maintaining sustainable riverine transportation of bulk goods (primarily agricultural and mining commodities). The rate of aggradation of sediment in a waterway is directly related to both the rate of sediment erosion from upland and river bank sources (sediment yield) and the energy in the river to effectively transport the sediment through the waterway system (sediment transport). Historically, methods used for waterway development have included trial and error or rules of thumb associated with river training structures and chute cut-off canals or engineering of navigation locks and dams. More …

Geotextile Tubes And Their Application To Dewatering, Kevin R. Morgan

College of Graduate Studies: Theses & Dissertations

Geotextile tubes are a proven cost-effective technology offering speed, efficiency, and minimal impact to the environment for dewatering of sediment or sludge from dredging operations. Common applications include: removal of solids from municipal water and waste water treatment, agricultural remediation, marine dredging operations, construction dewatering, and beach preservation and protection. Geotextile tubes are manufactured in a variety of configurations.

Geotextile tubes are used for a wide variety of environmental applications including dewatering and slurry containment. One of the most important design aspects of the tubes themselves is the ability to be flexible and expand and hold form under high pressure …

Water And Nutrient Reuse Within Closed Hydroponic Systems, Emerson Christie

College of Graduate Studies: Theses & Dissertations

Currently, little research exists on the maintenance of individual nutrient balance within the nutrient solutions of closed hydroponic systems and how this maintenance may result in reductions in water and nutrient consumption. In this study, a nutrient solution management procedure was developed to maintain outputs while minimizing inputs. Lactuca sativa (lettuce) crops were grown in six closed hydroponic systems utilizing the nutrient film technique. Electrical conductivity was used as the primary indicator of nutrient solution quality and determined if the nutrient solution was discarded and replaced (control systems) or restored (test systems). Restorations in test systems were made individually to …

Numerical Evaluation Of The Extended Endplate Moment Connection Subjected To Cyclic Loading, Mehdi Ghassemieh, Mehdi Jalalpour, Ali Akbar Gholampour

Civil and Environmental Engineering Faculty Publications

In this paper, the seismic behaviour of extended endplate moment connection is analysed using finite element method (FEM). First, an existing test setup is modelled and analysed using ANSYS computer program. The model is validated by comparing the results from the finite element with the experimental ones. Afterwards, by changing the dimensions of members of the connection, their effect on the overall seismic performance of connection is investigated. The results show that by enlarging the column depth and stiffening the connection, the seismic performance is improved and the thickness of endplate should be chosen in a way that its moment …

Numerical Simulations Of Dynamic Behavior Of Polyurea Toughened Steel Plates Under Impact Loading, Chien-Chung Chen, Daniel G. Linzell

Department of Civil and Environmental Engineering: Faculty Publications

The objective of the work discussed herein is to develop a nonlinear 3D finite element model to simulate dynamic behavior of polyurea toughened steel plates under impact loading. Experimental and numerical work related to model development are presented. Material properties are incorporated into numerical models to account for strain-rate effects on the dynamic behavior of polyurea and steel. One bare steel plate and four polyurea toughened steel plates were tested under impact loading using a pendulum impact device. Displacement time-history data from experimental work was used to validate the numerical models. Details on material model construction, finite element model development, …

Assessment Of Load Sharing Members In An Anti-Ram Bollard System, Scott Kinney, Daniel Linzell, Edward O'Hare

Department of Civil and Environmental Engineering: Faculty Publications

Due to the increased frequency, scale, and danger of malicious attacks carried out by Vehicle Borne Improvised Explosive Devices (VBIEDs), anti-ram bollards have become a key element in the protection of critical structures. This study focused on the evaluation of above grade load sharing members in a steel anti-ram bollard system in an attempt to develop efficient load sharing mechanisms that improve the structure’s ability to resist vehicle impacts, while concurrently remaining aesthetically pleasing to the general public. A computational assessment was completed using calibrated LS-DYNA finite element models to determine if effective load sharing member configurations and designs could …

Study On Surface Permeability Of Concrete Under Immersion, Jun Liu, Feng Xing, Biqin Dong, Hongyan Ma, Dong Pan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, concrete specimens are immersed in ultrapure water, to study the evolutions of surface permeability, pore structure and paste microstructure following the prolonging of immersion period. According to the results, after 30-day immersion, the surface permeability of concrete becomes higher as compared with the value before immersion. However, further immersion makes the surface permeability decrease, so that the value measured after 150-day immersion is only half that measured after 30-day immersion. The early increase in surface permeability should be mainly attributed to the leaching of calcium hydroxide, while the later decrease to the refinement of pore structure due …

Parametric Analysis Of Resilient Modulus Modeling For Recycled Asphalt Pavement In Base Layer, Ehab Noureldin, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The resilient modulus (M_R) has been found to be the most important parameter in the Mechanistic-Empirical Pavement Design Guide (MEPDG) for the base layer. A literature review showed that the use of recycled asphalt pavement (RAP) in the base layer had many economic and structural benefits. The prediction of M_R with the specific MEPDG model for the base layer mixed with RAP was found to be reliable for several field conditions. However, further studies of the MEPDG model are needed for an understanding of the physical meaning of each parameter in the model. The most important factor …

Effects Of Interaction Conditions On Internal Network Structure Of Crumb Rubber-Modified Asphalts, Mohyeldin Ragab, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Investigation of the effect of interaction conditions on the development of the internal network structure of crumb rubber-modified asphalt (CRMA) was carried out. Enhancements in the CRMA physical properties, such as stiffness, expressed in the complex modulus (G*), and elasticity, expressed in the phase angle (δ), as a result of the development of three-dimensional (3-D) entangled network structure were achieved. These results came from controlling the interaction conditions of CRMA synthesis to regulate the crumb rubber-modified (CRM) components that were responsible for the formation of the 3-1) entangled network structure. Dissolution tests and thermogravimetric analysis (TGA) were performed on the …

Effect Of Crumb Rubber Dissolution On Low-Temperature Performance And Aging Of Asphalt-Rubber Binder, Amir Ghavibazoo, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binder plays a critical role in defining the low-temperature performance of asphalt pavement, and, therefore, enhancing its mechanical behavior at low service temperatures through modification always has been of great interest. Crumb rubber modification of asphalt is one of the common practices in the industry. However, the effect of a crumb rubber modifier (CRM) on low-temperature performance of the binder is not well understood. A CRM swells by absorbing the aromat-ics and light molecular components of asphalt at low interaction temperatures (i.e., 160°C) and dissolves at higher interaction temperatures (i.e., 190°C, 220°C). Each of those activities affects the performance …

Two Driven Pile Load Tests For Use In Missouri Lrfd Guidelines, Matthew Garry Stuckmeyer

Masters Theses

"A static pile load test program was initiated by the Missouri Department of Transportation (MoDOT) to evaluate the use of pile load tests in Missouri LRFD guidelines. The program's approach involves two phases to achieve the appropriate levels of reliability for driven piles in the state of Missouri. This thesis focuses on the data collection efforts of Phase 1. Two quick static pile load tests were performed to failure on test piles in the Southeast Lowlands geologic region of Missouri. The piles were dynamically monitored during installation and subsequent restrike tests performed. The results of the static and dynamic pile …

The Effects Of Rain On Traffic Safety And Operations On Florida Freeways, Michelle L. Angel

UNF Graduate Theses and Dissertations

Although the association between weather and traffic variables or crash events appear intuitive to motorists, quantifying the effects that weather, especially rain, has on driver response in travel speeds, traffic demands, and susceptibility of accident occurrence is needed to evaluate practical aspects of traffic operations and safety measures. Previous studies have researched driver responses to inclement weather on roadways located primarily in northern and western regions of the United States (U.S.), Canada, and Europe. However, driver familiarity to local weather conditions is a factor that should be considered in determining inclement weather effects on traffic variables and crash occurrence. This …

A Unified Bond Theory, Probabilistic Meso-Scale Modeling, And Experimental Validation Of Deformed Steel Rebar In Normal Strength Concrete, Chenglin Wu

Doctoral Dissertations

"Bond between deformed rebar and concrete is affected by rebar deformation pattern, concrete properties, concrete confinement, and rebar-concrete interfacial properties. Two distinct groups of bond models were traditionally developed based on the dominant effects of concrete splitting and near-interface shear-off failures. Their accuracy highly depended upon the test data sets selected in analysis and calibration. In this study, a unified bond model is proposed and developed based on an analogy to the indentation problem around the rib front of deformed rebar. This mechanics-based model can take into account the combined effect of concrete splitting and interface shear-off failures, resulting in …

Rapid Repair Of Severely Damaged Rc Columns Under Combined Loading Of Flexure, Shear, And Torsion With Externally Bonded Cfrp, Ruili He

Doctoral Dissertations

"This research aimed to develop a technique to rapidly repair reinforced concrete (RC) bridge columns for emergency service restoration after severe earthquake damage has occurred. Experimental and analytical studies were conducted to study the performance and effectiveness of the proposed repair method. The experimental study included a series of 1/2-scale RC square bridge columns originally tested to failure under constant axial and increasing cyclic lateral loadings resulting in combined flexure, shear, and torsion with different torsional-to-flexural moment ratios. Using externally bonded carbon fiber reinforced polymer (CFRP) sheets, each column was repaired over a 3-day period and then retested under the …

Plant Uptake Of Environmental Contaminants: Applications In Phytoscreening, Matthew Alan Limmer

Doctoral Dissertations

"Plants interact directly with their surroundings, extracting nutrients and water from the subsurface to support growth and development of the plant. Through the roots, plants also exude and uptake numerous chemicals. Many of the pathways can also be used by environmental contaminants to be translocated to above ground plant tissues. Such uptake of contaminants has proven useful in remediation and phytoscreening - the use of plants to delineate contaminant plumes. Sampling of trees at contaminated field sites has been used to identify areas of groundwater contaminated with a variety of chlorinated solvents. The use of plants as contaminant biosensors requires …

Seismic Repair Of Bridge Columns With Interlocking Spirals And Fractured Bars, Yang Yang

Doctoral Dissertations

"During earthquakes, reinforced concrete (RC) bridge columns may experience different levels of damage such as cracking, spalling, or crushing of concrete and yielding, buckling, or fracture of reinforcing bars. This study developed and assessed permanent and emergency methods to repair damaged bridge columns with fractured longitudinal reinforcement through experimental and modeling work. The permanent repair method involved replacement of the plastic hinge region by removal of spirals, replacement of longitudinal bar segments by mechanically splicing with new bars segments attached with mechanical couplers, replacement of concrete, and installation of an externally bonded carbon fiber reinforced polymer (CFRP) jacket. The emergency …