Civil and Environmental Engineering Commons^™

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 …

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 …

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 …

An Explanatory And Comparative Analysis Of Freight Transportation In Eu And U.S. Highways, Luis Alberto Hernandez

Open Access Theses & Dissertations

This thesis provides resources for data collection regarding road freight transportation in the Unites States and the European Union, as well as an explanatory description of data available at each source. Afterwards, individual analysis of the current state of affairs of the highway freight transportation systems in U.S. and EU are performed. Thereafter, an explanatory and comparative analysis between the two land freight transportation systems is performed in terms of regulatory authorities and associations, trucks volume flow, freight weight and volume flow, major issues affecting the system, infrastructure funding sources, and major logistics hubs. Besides, a correlation analysis was performed …

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 …

Water Recovery From Silica Saturated Ro Concentrate By The Concentrate Enhanced Reverse Osmosis Process, Gautam Patwardhan

Open Access Theses & Dissertations

Membrane fouling due to silica precipitation during reverse osmosis (RO) continues to be documented as the most common challenge in attaining stable continuous operation of RO systems across water treatment plants (1). Silica scale precipitation is time dependent and involves multiple steps leading to aqueous polymerization, condensation of polymers to form colloids, and deposition onto a solid surface (2). Exceeding the solubility of silica, widely considered to be in the range of 100-140 ppm, under a pH of 8 at 25 °C by various researchers, results in the precipitation of silica on the membranes, thereby limiting water recovery. Once the …

Permit Tool: Development Of An Algorithm To Determine Performance Life Of Hma Mixes In Texas, Luis Alberto Torres Escobedo

Open Access Theses & Dissertations

A number of hot mix asphalt (HMA) types, such as permeable friction course (PFC), stone mastic asphalt (SMA), performance design mixes and conventional dense graded mixes are currently used to construct or overlay Texas roads. One of the important inputs into current pavement design programs used by the Texas Department of Transportation (TxDOT) is the performance lives of HMA mixes. To determine the best mix type for a particular job or to analyze the performance of a mix or a road, a new system can be developed to rationally quantify the HMA mix performance. This system must have access to …

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 …

Safety Measures For Trucks: A Comparison Between Eu And U.S., Jan Kapusta

Open Access Theses & Dissertations

Road transportation is playing an important role in almost all of the freight movements and contributes to the economy. It has the highest share in the modal division of transported goods. This situation is not about to change in next years to come. Therefore, it is necessary to change the current situation and create rules and regulations that would lead to decrease in number of accidents either in EU or in U.S. The goal of this research is to analyze selected parameters related to the safety of truck transportation in EU and in U.S. This thesis also identifies and compares …

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 …

Transatlantic Maritime Transportation Between The Czech Republic And The United States, Petr Toman

Open Access Theses & Dissertations

Maritime transportation is the backbone of today´s world trade and therefore there special attention should be paid to all subjects concerning this mode of transportation. It is also necessary to complement maritime transportation by other modes, such as rail and/or truck (road). This thesis deals with the problems of maritime transportation and provides the summary of recent developments, trends and statistics mainly on Transatlantic maritime routes (Europe to U.S.). Besides maritime transportation, this thesis also reviews the trends and statistics of rail and truck (road) transportation in U.S. and Europe.

The second part of thesis seeks to create a mathematical …

Sustainable Public Transportation In Large Cities: Demand Estimation, Tadeas Umlauf

Open Access Theses & Dissertations

Public transportation helps to decrease the negative externalities caused by people's mobility. In many countries, the total number of vehicles and traffic has risen many times in the last decades but there is limited space to improve infrastructure in the cities. Large cities all over the world have a lot of issues with congestion, traffic noise, emission of greenhouse gases, and accidents. According to many international examples, sustainable public transportation in combination with synergistic projects (park & ride, kiss & ride, bike & ride) can help to overcome these issues. Therefore new transit modes and routes have been implemented in …

Testing And Strengthening Bridge Connections, Christopher Higgins, Peter Dusicka, Michael Scott

TREC Project Briefs

Researchers evaluate and improve the strength of gusset plate connections, essential pieces in bridge design that can fail due to buckling.

Measurements And Transient Multistep Outflow Simulation Of Soil-Water Characteristic Curve For Soils Modified With Biopolymers, Xiaoyi Zhao

Masters Theses

"In recent decades, biopolymers have shown promising applications in soil modification due to its environmental friendly nature. Most of the studies, however, focused on mechanical properties at saturated or unsaturated conditions. The study on unsaturated soil behaviors under controlled pore air and pore water pressures were limited. Soil-water characteristic curve (SWCC), relating water content with matric suction is a key property to evaluate unsaturated soils. With SWCC, other soil properties, such as hydraulic conductivity and shear strength can be estimated. In this study, SWCC of sands modified with different biopolymers were measured with both Tempe cell and Fredlund SWCC device. …

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

Program Accreditation Reports (2013-2023)

This is the revised 2013 report for 2014.

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

Longitudinal Analysis Of Crash Frequency Data, Mojtaba Ale Mohammadi

Doctoral Dissertations

"This study comprises mainly of three papers. First, a systematic evaluation of the effects of Missouri's Strategic Highway Safety Plan between 2004 and 2007 is presented. Negative binomial regression models were developed for the before-through-change conditions for the various collision types and crash severities. The models were used to predict the expected number of crashes assuming with and without the implementation of MSHSP. This procedure estimated significant reductions of 10% in crashes frequency and a 30% reduction for fatal crashes. Reductions in the number of different collision types were estimated to be 18-37%. The results suggest that the MSHSP was …

Bridge Deck Condition Assessment Using Destructive And Nondestructive Methods, Brandon Tyler Goodwin

Masters Theses

"This study investigates two bridge decks in the state of Missouri using both nondestructive and destructive testing methods. The Missouri Department of Transportation (MoDOT) is responsible for the monitoring and maintenance of over 10,000 bridges. Currently monitoring of these bridges includes a comprehensive visual inspection. In this study, ground-coupled ground penetrating radar (GPR) is used to estimate deterioration, along with other traditional methods, including visual inspection, and core evaluation. Extracted core samples were carefully examined, and the volume of permeable pore space was determined for each core. After the initial investigation, the two bridges underwent rehabilitation using hydrodemolition as a …

Comparison Of Costs Of Personal Protective Equipment For All Workers To Avoid Costs Of Fall Accidents, Sultan Noori Al-Karawi

Masters Theses

"The construction industry is one of the most important industries in the United States. It is the biggest contributor in the growth of the U.S. economy. Despite the great achievements and prominent role for this sector in the U.S. economy, the construction industry is suffering from neglect and dereliction by related government institutions and private companies. This neglect led to formation of a negative image about the construction industry that has caused a deep impact in productivity and economic growth. One of the reasons is a high percentage of accidents that occur within the construction industry which leads to injuries …