Civil Engineering Commons^™

Internal Design Of Mechanically Stabilized Earth (Mse) Retaining Walls Using Crimped Bars, Bernardo A. Castellanos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current design codes of Mechanically Stabilized Earth (MSE) Walls allow the use lower lateral earth pressure coefficient (K value) for designing geosynthetics walls than those used to design steel walls. The reason of this is because geosynthetics walls are less rigid permitting the wall to deform enough to work under active pressures instead of at rest pressures as in steel walls.

A new concept of crimped steel bars was recently introduced. This new type of bar was tested for tension and pullout behavior. Results on tests made on crimped bars show that putting those crimps in the steel bar will …

Increased Functionality Of Floodplain Mapping Automation: Utah Inundation Mapping System (Utims), Brian K. Stevens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Floodplain mapping has become an increasingly important part of floodplain management. Floodplain mapping employs mapping software and hydraulic calculation packages to efficiently map floodplains. Modelers often utilize automation software to develop the complex geometries required to reduce the time to develop hydraulic models.

The Utah Inundation Mapping System (UTIMS) was designed to reduce the time required to develop complex geometries for use in floodplain mapping studies. UTIMS reduces the time required to develop geometries used in floodplain management studies. The automated geometries developed include: flood specific river centerlines, bank lines, flow path lines, cross sections, and areal averaged n-value polygons. …

Statistical Modeling And Analysis Of Injury Severity Sustained By Occupants Of Passenger Vehicles Involved In Crashes With Large Trucks, Ahmad Koupaenejad

UNLV Theses, Dissertations, Professional Papers, and Capstones

Crashes are the result of complex interactions between several factors representing driver, roadway, vehicle, and environmental characteristics. Understanding to what degree each factor contributes to the severity of a crash is not a simple task. The outcomes of crashes in the US have been an average of 42,000 deaths and 3 million injuries per year. To better understand the role of significant contributors to crashes, three sets of models using multinomial logit and one using ordered probit were calibrated. To calibrate these models, forty two independent predictor variables including driver/occupants characteristics, crash environment at the crash location, crash characteristics, and …

Performance Of Nevada’S Aggregates In Alkali-Aggregate Reactivity Of Portland Cement Concrete, Mohammad Shahidul Islam

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alkali-aggregate reaction (AAR) is a form of distress that occurs in concrete and results in serviceability problems, cracks, spalling, and other deterioration mechanisms. There are two categories of AAR, namely, alkali-silica reaction (ASR) and alkali-carbonate reaction (ACR). Alkali-silica reaction is one of the most recognized deleterious phenomena in concrete, and has been a major concern since its discovery in the 1940s. The reaction which occurs between reactive silica or silicates present in some aggregates and alkalis of Portland cement produces an alkali-silica gel that expands in the presence of moisture resulting in concrete cracks. ACR is also a chemical reaction …

A Comparison Of Small Scale Laboratory Experiments With The Environmetnal Protection Agency Reccomended Dense Gas Dispersion Models: An Assessment Of The Validity Of Salt Bath Modeling Of Atmospheric Flows, Katie Betz

All Theses

Accurate dense gas dispersion modeling is important in a number of fields from modeling smoke movement in a room to the spreading of dense toxic gas releases such as resulted from the Chlorine spill in Graniteville, SC in 2005. To this end, a series of small scale laboratory experiments using instantaneous releases of a cylindrical, finite volume of dense salt water were performed. In the experiments, the horizontal spread of the dense liquid over a flat surface(i.e. gravity current front position over time) was measured.
The results of these small scale experiments were compared to two dense gas dispersion models …

Long-Term Performance Of Pavement Markings On Primary And Secondary Roads, Joshua Johnson

All Theses

This research analyzes waterbased and thermoplastic pavement markings on primary and secondary roads in South Carolina. The primary objective of this research was to develop retroreflectivity degradation models for these two pavement marking materials, as well as determine the expected useful life of the markings. Predicting retroreflectivity and marking life is important so that state DOTs may efficiently replace markings in order to reduce safety hazards as well as maintenance costs.
Data collection for this research lasted 21 months, where retroreflectivity of pavement markings was measured on over 100 primary and secondary roads in South Carolina. Variables such as marking …

Liquefaction Analysis Of Three Pleistocene Sand Deposits That Did Not Liquefy During The 1886 Charleston, South Carolina Earthquake Based On Shear Wave Velocity And Penetration Resistance, Aaron Geiger

All Theses

The results of geotechnical investigations at three sites located in the South Carolina Coastal Plain are presented in this thesis. The three sites are called the Hobcaw Barony Borrow Pit site located near Georgetown, SC; the Rest Area Ponds site near Walterboro, SC; and the Lowcountry Sand & Gravel site, also near Walterboro. Near-surface sand deposits at these sites ranged in geologic age from 200,000 to greater than 1,000,000 years. These three sites lie well outside the region of most liquefaction effects observed following the 1886 Charleston earthquake. Investigations conducted at the sites include seismic cone penetration tests with pore …

Comparision Of Open Graded Friction Course Mix Design Methods Currently Used In The United States, Laura Kline

All Theses

This research compares the open graded friction course (OGFC) mix design methods which are currently being used in the United States. OGFCs are a type of porous pavement that have been used in the United States since 1944, but has provided inconsistent and highly variable performance results. The design procedures for several agencies were obtained, and then compared for similarities. All of the design methods were then conducted to determine the optimum binder content. The optimum binder content (OBC) of a single aggregate gradation for each method was tested for properties and performance characteristics.
The design methods which are currently …

Performance Evaluation Of Sbs Modified Asphalt Mixtures Using Warm Mix Technologies, Hakseo Kim

All Theses

The need for more sustainable methods and techniques in industry has been increasing and it is important to respond to the needs of society and address issues surrounding its environment and health. In order to better introduce such new and more sustainable methods, it is necessary to combine existing and proven methods with new technology. The main idea of this research was to use the established industry standard of using Styrene Butadiene Styrene (SBS) modified binder and combine it with the relatively new Warm Mix Asphalt (WMA) technology in order to create a more sustainable and eco-friendly asphalt paving process. …

A Concise Model Of 3x7 Wire Rope Used In Cable Guardrail Systems, Cody S. Stolle

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Wire rope is a versatile, flexible, high-strength member that is used in many mechanical systems. However, due to the complexity of wire rope, analytical investigations have been relatively limited. Previous attempts to create simplified models of wire rope were not validated with physical testing and used a cumbersome beam-and-shell or beam-and-solid method for simulating the wire rope. An improved LS-DYNA model of 19-mm diameter 3x7 wire rope commonly used in roadside cable guardrail installations has been developed. A Belytschko-Schwer beam element was selected along with material *MAT_166. Since wire rope displays internal damping due to friction of strands and wires, …

Polarization Of Galvanic Point Anodes For Corrosion Prevention In Reinforced Concrete, Margareth Dugarte

USF Tampa Graduate Theses and Dissertations

The polarization performance of two types of commercial galvanic point anodes for protection of reinforced steel around patch repairs was investigated. Experiments included measurement of the polarization history of the anode under constant current impressed by galvanostatic circuits and in reinforced concrete slabs. The tests revealed, for both types of anodes, a potential-current function (PF) indicating relatively little anodic polarization from an open circuit potential at low current levels, followed by an abrupt increase in potential as the current approached an apparent terminal value. Aging of the anodes was manifested by a continually decreasing current output in the concrete tests, …

Sustainable Portland: Implementation Series 3, New England Environmental Finance Center

Climate Change

This report is the third in a series of efforts by students at the Muskie School of Public Service, Community Planning and Development Master’s program, in a core class called “Sustainable Communities.” In this course students seek to understand principles of sustainability and how efforts to implement Sustainability programs can become more successful. The report assembles term papers students completed on particular efforts by municipalities, universities, and other groups to achieve sustainability goals. Students worked on each project in a service learning format with real world clients. They were asked to fashion their papers around lessons learned by other organizations …

Achieving The Vision Through High Ethical Standards, Sarah E. Bertke

Ohio Valley Regional Student Conference

No abstract provided.

Perpetual Pavement Analysis For The Marquette Interchange Instrumentation Project, Nicholas James Hornyak

Dissertations (1934 -)

With the emergence of the mechanistic-empirical pavement design process, development of pavements rely on the structural response and fatigue characteristics of pavement materials due to traffic loads. In the past, pavement design has been almost entirely based on empirical data. One area of interest in designing hot-mix asphalt (HMA) pavements is the fatigue life of the pavement, which has been shown to be dependent on the horizontal strain in the pavement.

This research is focused on measuring the structural response of a pavement located within the Marquette Interchange Project in order to analyze fatigue behavior with great detail. Virtually all …

Development Of A Geopolymer-Based Cementitious Coating For The Rehabilitation Of Buried Concrete Infrastructure, Carlos Montes

Doctoral Dissertations

The current research project was devoted to the incorporation of geopolymers as a new material for Trenchless projects, taking advantage of their properties in a field in which they had not been used before, providing a substantial help to municipalities to meet their rehabilitation needs. Trenchless Technologies are a family of methods, materials and equipment capable of being used for the installation of new or replacement or rehabilitation of existing underground infrastructure with minimal disruption to surface traffic, business, and other activities.

The dissertation research work described herein is divided into six primary objectives: (1) the evaluation of geopolymer as …

Computational And Experimental Characterization Of Bituminous Composites Based On Experimentally Determined Properties Of Constituents, Pravat Karki

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

The stiffness of asphalt concrete mixtures is characterized in terms of the dynamic modulus for designing the thickness of flexible pavements. The dynamic modulus value of asphalt concrete is either determined experimentally or predicted by using empirical, semi-empirical, analytical or computational micromechanics models. This study proposes to use a computational micromechanics model to predict the dynamic modulus of asphalt concrete mixtures based on the experimentally determined properties of the constituents in the heterogeneous microstructure. The model defines asphalt concrete mixtures as the composites of two different homogeneous isotropic components – the viscoelastic fine aggregate matrix phase and the elastic aggregate …

Use Of Dynamic Cone Penetration And Clegg Hammer Tests For Quality Control Of Roadway Compaction And Construction, Hobi Kim, Monica Prezzi, Rodrigo Salgado

JTRP Technical Reports

Soil compaction quality control presently relies on the determination of the in-place compacted dry unit weight, which is then compared with the maximum dry unit weight obtained from a laboratory compaction test. INDOT requires that the in-place dry unit weight for compacted soil be over 95% of the laboratory maximum dry unit weight. In order to determine the in-place dry unit weight, INDOT engineers generally use nuclear gauges, which are hazardous and also costly because of the required safety precautions. Thus, several alternative tests such as the Dynamic Cone Penetration Test (DCPT) and the Clegg Hammer Test (CHT) were introduced …

Geotechnical Design Based On Cpt And Pmt, Daehyeon Kim, Younjin Shin, Nayyar Siddiki

JTRP Technical Reports

This research presents the correlation of undrained shear strength based on the cone resistance from the cone penetration test (CPT) for clayey soils in Indiana. It utilized the field cone penetration test program including the CPT, the index test, the one dimensional test and the triaxial test. The cone factor, which is essential to reliable estimation of undrained shear strength from cone resistance, has been evaluated considering the plasticity index of soils. The cone factor is influenced by the penetration rate during the CPT and test methods that are used for obtaining the undrained shear strength. The rate effect of …

Analyzing The Effects Of Led Traffic Signals On Urban Intersection Safety, Deogratias Eustace, Valerie E. Griffin, Peter W. Hovey

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

In 2002, there were 1,299,000 crashes at signalized intersections in the United States. These crashes account for approximately 21 percent of total crashes and about 24 percent of all fatal and injury collisions. The social and financial impact of this number of collisions is substantial. The Federal Highway Administration (FHWA) and other agencies have recognized the detrimental effects of intersection crashes on our society and continue to fund research that will lead to a decrease in crash frequency. Numerous countermeasures have been tested for their potential to reduce crashes. Infrastructure improvements such as the construction of left-turn lanes, the removal …

A Simple Technique For Surface Area Determination Through Supercritical Co2 Adsorption, Mahmud Sudibandriyo

Makara Journal of Technology

The measurement of specific surface area of porous materials has long been important in physical sciences and is currently growing in importance in applied and environmental science. Numerous systems have been developed for surface area measurement by gas adsorption. Commercial systems are available which can measure a wide range of absolute surface area with relative ease. However, their cost is often prohibitive. In this study, an inexpensive apparatus for surface area measurement has been set up to be used for measuring supercritical adsorption of CO2. The Ono-Kondo Lattice model was used to represent the adsorption isotherm and to determine the …