Geotechnical Engineering Commons^™

Development Of Soil Water Characteristic Curves Through Control Of Relative Humidity, Lauren E. Johnson, Julia I. Loshelder, Richard A. Coffman

Civil Engineering Undergraduate Honors Theses

The relationship between soil suction and soil water content in unsaturated soil mechanics is important but can be difficult to measure. The objective of the research described herein was to develop soil water characteristic curves (SWCC) from relative humidity values by incorporating the use of glycerin-water mixtures. Glycerin-water mixtures can be used to achieve different relative humidity levels by varying the concentration of glycerin within the mixture. The relative humidity created by each mixture was measured with a relative humidity sensor, and the relative humidity values and Kelvin’s equation were used to compute the total suction.

Soil water characteristic curves …

Investigation Of Micp Based 3d Printed Soils, Kathleen Weston

Civil Engineering Undergraduate Honors Theses

The advent of additive manufacturing, often called 3D printing, offers potential for new and more sustainable soil improvement techniques. Previous research at the University of Arkansas has examined Microbially Induced Calcite Precipitation (MICP) as a possible binder option that is a more sustainable alternative to Portland cement and can be used in remote areas where Portland cement may not be available. The objective of this research is to develop an increased understanding of the potential of utilizing MICP as a spray binding technique for applications in 3D printed soils. The specific goals of this research include: examining the effectiveness of …

Development Of Deep Shear Wave Velocity Profiles And An Approach To Generate Site Signature Consistent Pseudo Shear Wave Velocity Profiles In The Mississippi Embayment, Ashraf Kamal Himel

Graduate Theses and Dissertations

This dissertation details the development of a surface wave method (SWM) technique to generate deep shear wave velocity profiles (VS profiles), applying this technique at 24 sites across the Mississippi embayment and developing an approach to generate pseudo site signature consistent VS profiles from velocity functions and fundamental frequency. In the presented SWM technique, active and passive source surface wave measurements are inverted along with fundamental frequency to develop a site signature consistent VS profile. Multiple transformation methods, including MSPAC, HRFK and FK are used to resolve experimental dispersion data from surface wave measurements. SWM VS profile at the Central …

Cyclic Behavior Of Laterally Skewed Special Moment Frame Connections: Experimental Testing And System-Level Analyses, Mohammad Hossein Kashefizadeh

Graduate Theses and Dissertations

Special moment frames (SMFs) are frequently used in high seismic areas for architecturally constrained designs. SMFs provide lateral system stiffness without the use of braces that often obstruct views and architectural features. Current American Institute of Steel Construction (ASIC) provisions (AISC 341-16) provide prequalified SMF connection details; however, all prequalified details only consider orthogonal connections between the beam and column. This dissertation investigates the effect of adding skew within SMF beam-to-column connections. The study presented herein involves system-level dynamic time-history analyses of skewed SMF connections, the analytical component-level investigation into the effect of the concrete slab on behavior of the …

Rapid Non-Nuclear In Situ Density And Moisture Content Measurement Of Soil, Mateo Lopez

Graduate Theses and Dissertations

Adequate soil compaction is important for the stability and safety of structures and transportation infrastructure. Thus, methods utilized to obtain properties that control the quality of compaction in the field are essential to ensure proper construction. These properties include; total density, dry density, total unit weight and dry unit weight of the compacted soil. The most common method to measure these properties in the field is the Nuclear Density Gauge. Moisture content and density results are obtained using the Nuclear Density Gauge in one to four minutes. However, this method requires specialized training and strict storage requirements in addition to …

Comparing Actively Managed Mutual Fund Categories To Index Funds Using Linear Regression Forecasting And Portfolio Optimization, Luke Weiner

Industrial Engineering Undergraduate Honors Theses

The global investment industry offers a wide variety of investment products especially for individual investors. One such product, index funds, which are younger than actively managed mutual funds, have typically outperformed managed funds. Despite this phenomenon, investors have displayed a tendency to continue investing in actively managed funds. Although only a small percentage of actively managed funds outperform index funds, the costs of actively managed funds are significantly higher. Also, managed fund performances are most often determined by their fund category such as growth or real estate. I wanted to answer the following question for individual investors: can we …

Additive Manufacturing Of Soil Using Bio-Cementation, Christina Childress

Graduate Theses and Dissertations

Microbially Induced Calcite Precipitation (MICP) is an emerging soil treatment technique that is proven to increase strength, decrease erosion, reduce liquefaction risk, enhance slope stability, decrease compressibility, decrease swelling potential, and overall create a more competent soil. The benefits and applications of MICP are broad, and this research seeks to broaden them further by developing a single-phase additive manufacturing application with no treatment time delay. This is done by analyzing layering behaviors of five USCS soil classifications (100 % Ottawa sand, sand clay mixtures, and 100% lean clay) which provides insight into process variables such as the solution volume and …

Identification Of Phosphorous Loading Point Source Facilities To 303(D) Listed Nutrient Impaired Waters Through Watershed Delineation Using Arcgis For Life Cycle Assessment Applications, John Zimmerman

Chemical Engineering Undergraduate Honors Theses

The work done for this project is part of a larger “life cycle assessment (LCA) of novel electrochemical phosphorus recovery technology at the wastewater treatment plant and U.S. watershed scales” (Morrissey 2019). The goal of that LCA is to determine “environmental impacts of implementing electrochemical struvite recovery at the wastewater treatment plant, U.S watershed, and global scales” (Morrissey 2019). This project’s goal is to identify locations deemed more sensitive to eutrophication impacts. The results will be used as part of the life cycle inventory (LCI) accounting for geographically explicit phosphorus flows. The waters identified as impaired were sourced from the …

Applications Of Masw And Mhvsr Techniques For Infrastructure Evaluation With A Focus On The Effects Of Different Transformation Techniques And Near-Field Effects On Derived Dispersion Data, Salman Rahimi

Graduate Theses and Dissertations

This dissertation is aimed at understanding two aspects of active surface wave methods to improve the accuracy and reliability of this method. These include (1) the performance of four common wavefield transformation methods for the multichannel analysis of surface wave (MASW) data processing and (2) near-field effects. Toward this end, extensive field measurements were conducted considering different factors affecting these two topics. The MASW and microtremor horizontal to vertical spectral ratio (MHVSR) were then employed to examine their efficiency for infrastructure health monitoring.

Regarding the performance of the four common transformation techniques, it was observed that for sites with a …

Shallow 3d Shear Wave Velocity Model And Revised Site Period Prediction Map For The Mexico City Basin, Rendon Martin Rieth

Graduate Theses and Dissertations

The goal of this study was to revise the existing site period prediction map and to develop a shallow 3D shear wave velocity model of the Mexico City Basin. To accomplish this goal, an extensive literature review was performed to compile as much pertinent shear wave velocity and site period data for the region. In total, 75 sites were used to revise the site period prediction map and 40 sites were used to develop the shear wave velocity model. The 2004 Complementary Technical Standards of Mexico site period prediction map was adjusted with new site period measurements across the basin …

Analysis Of Shear-Strength In Weathered Shale Strata Along A Highway Slope Failure Site In Northwest Arkansas, Olivia Overton

Civil Engineering Undergraduate Honors Theses

Slope failures cost millions of dollars per year to repair and can be deadly. Accurate modeling of slope conditions, including soil parameters, water table locations, and depth to bedrock, are essential to determining the overall stability of a slope. This project is a continuation of the work completed in 2019 by a former University of Arkansas researcher, Vanessa LeBow. LeBow RocScience used Slide2 modeling software to model two highway embankment slopes in Northwest Arkansas that experienced slope movement to determine whether increased use of geophysical data could increase the accuracy of slope stability models. A parametric study of shear strengths …

When It Rains, It Pours: A Case Study Of Spatio-Temporal Variations In High-Intensity Precipitation Events In Arkansas, Deanna Mantooth-Hendrix

Graduate Theses and Dissertations

Climate change is having an impact on weather systems and ecosystems worldwide. Glaciers are receding, oceans are acidifying, hurricanes are stronger, and extreme precipitation is increasing in frequency. Even with the wealth of data and knowledge about the threat of climate change, some places are slow to adapt because they think that the impact to their ecosystem will not be severe. The goal of this project was to determine if climate change is having an impact on extreme precipitation in the top urban areas of Arkansas. The major concern with an increase in extreme events in urban areas is flooding. …

Cement Stabilized Crushed Stone Base Course Strength And Stiffness Analysis, Andrew Deschenes

Graduate Theses and Dissertations

Approximately 70 – 80% of state departments of transportations (DOTs) utilize the 1993 AASTHO Guide for Design of Pavement Structures (1993 AASHTO) [1] for structural design of pavements. A growing portion of DOT’s are beginning to implement the Mechanistic-Empirical Pavement Design Guide (MEPDG), referred to as AASHTOWare Pavement ME [2]. The 1993 AASHTO flexible guide applies empirically derived unitless strength values referred to as structural layer coefficients and structural numbers (SN) to pavement thickness and pavement types. The 1993 AASHTO rigid flexible guide utilizes the depth and strength of the concrete pavement, with the composite spring constant (kc), which is …

Effect Of Citric Acid On Slump, Compressive Strength, And Setting Time Of Belitic Calcium Sulfoaluminate Concrete, Israel Aguilar Rosero

Graduate Theses and Dissertations

Belitic calcium sulfoaluminate (BCSA) cement has well established advantages related to fast setting time, fast strength gain, long-term strengths, shrinkage, and sustainability. Due to its fast setting and hardening, this type of cement has historically been used to repair concrete structures, highways, and runways. This work provides much needed guidance on establishing mix design criteria for BCSA cement. Guidance is also given on the effects of set retarders on strength, slump, and setting times. Citric acid and a phosphonic acid-based admixture were tested as retarders for different concrete mixtures. Three studies were performed. In the slump study five different water …

Development Of Vs Profiles And Site Periods In The Mexico City Basin, Landon Joel Woodfield

Graduate Theses and Dissertations

This study presents dynamic site characterization measurements at 25 sites within the Mexico City Basin. The primary focus of the testing was along the western edge of the Mexico City Basin. At each site, active source Multi-channel Analysis of Surface Waves (MASW) arrays and passive source Microtremor Array Measurements (MAM) L-arrays and circular arrays were used to acquire dispersion data. Horizontal to Vertical Spectral Ratio (HVSR) data was collected to determine site periods at each location. These experimental dispersion data and site periods were fit using a joint inversion of Rayleigh and Love wave dispersion data and HVSR site period …

Development Of Multi-Axial Fatigue Retrofits For Lock Gate Components, Logan Verkamp

Graduate Theses and Dissertations

Lock gates are essential infrastructure components to the United State (US) supply chain. They create large cost savings and environmental benefits when compared with traditional methods of transport (freight and rail). Because of the large quantity of goods and dependence on these shipping chains, the US economy can be drastically affected by an unexpected gate closure. Unfortunately, many lock gates within the US have reached or exceeded their designed life. Due to the intensity of cyclic loads and the environment, fatigue cracks have become a prominent issue. Developed cracks near the pintle region (a joint which the gate rotates and …

Preliminary Investigation Of Required Bsca Amount For Soil Cement Mixtures, Mariel Mayori Rivero

Civil Engineering Undergraduate Honors Theses

The recent increase of flooding in the United States and the high expenses related to the damage that these floods have caused to waterway structures suggests a potential interest in rapid setting soil cement to make effective repairs. For this thesis, mix designs of soil only at three different sand-clay proportions were prepared and tested for moisture content and maximum dry density. Due to the early closing of the laboratory and research activities, reliable results were collected from the 70% sand and 30% clay proportions. At those proportions of soil, the optimum moisture content was found to be 8.88% with …

Soil Moisture Content Determination By Means Of The Electromagnetic Spectrum, Julia Loshelder

Civil Engineering Undergraduate Honors Theses

Soil moisture content provides information about the strength, permeability, and compressibility of the soil under investigation. In the research described herein, the relationship between moisture content and reflectance values obtained from spectroscopy was developed to investigate whether in-situ moisture content can be determined in a faster and more efficient way than the current methods. The soil under investigation was laboratory-compacted kaolinite clay mixed with pyranine dye. These specimens were placed beneath an ultraviolet light and a halogen illuminator where reflectance values were collected over a 24-hour period. Correlations were developed from the following methods: 1) spectral indices, 2) continuum analyses …

Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow

Graduate Theses and Dissertations

Slope failures in the United States alone cause millions of dollars in damage to infrastructure, threaten national monuments, create environmental hazards, and take an average of 25-50 lives a year. With the inevitable construction that occurs on slopes, it is imperative that the slopes be properly designed which requires a thorough understanding of slope grade, subsurface soil conditions, soil strength parameters, water table locations, and depth to bedrock across the entire site. The preferred method of data collection would be to use borings and other in-situ methods; however, sometimes due to cost constraints or site accessibility only a very limited …

Suitability Assessment For Integrated Urban Development In Makkah City Of Saudi Arabia, Mislat Alotaibi

Graduate Theses and Dissertations

Makkah – the third most populated city in Saudi Arabia with a population of 1,684,408 according to the 2010 demographic survey conducted by the Saudi General Authority for Statistics – is experiencing urban sprawl, which can be defined as an unplanned urban expansion that might degrade the environment and diminish the aesthetic view. This is a persisting problem in Makkah driven by multitude of processes involving the random expansion in its undeveloped land and the removal of its historic mountains surrounding Al-Masjid Al-Haram (the Holy Mosque) in an attempt to push the city limit of urban capacity within its administrative …

Development Of A Multimode Instrument For Remote Measurements Of Unsaturated Soil Properties, Sean Elliott Salazar

Graduate Theses and Dissertations

The hydromechanical behavior of soil is governed by parameters that include the moisture content, soil matric potential, texture, and the mineralogical composition of the soil. Remote characterization of these and other key properties of the soil offers advantages over conventional in situ or laboratory-based measurements: information may be acquired rapidly over large, or inaccessible areas; samples do not need to be collected; and the measurements are non-destructive. A field-deployable, ground-based remote sensor, designated the Soil Observation Laser Absorption Spectrometer (SOLAS), was developed to infer parameters of bare soils and other natural surfaces over intermediate (100 m) and long (1,000 m) …

The Development Of Initial Asphalt Mixture Acceptance Criteria Using The Scb Test And The I-Fit Test, Nathan Delman Parnell

Graduate Theses and Dissertations

Cracking has become the primary asphalt pavement distress in Arkansas. Arkansas along with other states have implemented a test to measure rutting resistance. This paper presents research to implement a cracking resistance test to further modify the Superpave volumetric asphalt mixture design method in Arkansas. The Illinois Flexibility Index Test (I-FIT) was the test chosen to analyze for this research. Two aging methods were tested, a short term oven aging (AASHTO R30 ST) and a long term oven aging (NCAT) method. Six asphalt mixtures were selected to be tested. The mixtures testes were recreated from Arkansas Department of Transportation (ARDOT) …

Displacement Derived Energy Levels For Harvard Miniature Compaction, Ana Laura Errigo, Julia Loshelder

Civil Engineering Undergraduate Honors Theses

Previously, the amount of energy provided by the Harvard Miniature tamper was adjusted by changing the number of blows per lift or the number of lifts or was not adjusted at all. However, this research was conducted to investigate the effect of adjusting the displacement of the spring (increased or decreased) to change the potential energy of the spring and therefore change the compacive effort with a specific type of soil. Thus, the objective was to match the compaction energies using the Harvard miniature method with the compaction energies obtained using the Proctor method. Specifically, the goal was to show …

Tension Splitting Strength Of Bcsa Concrete Cylinders, Andrew Steven Deschenes

Civil Engineering Undergraduate Honors Theses

The focus of this research was to compare the tension splitting strength (TSS) of belitic calcium sufloaluminate (BCSA) cement concrete to tensile strength predicted by the American Concrete Institute (ACI) and to similarly proportioned portland cement (PC) concrete. BCSA is a rapid-setting cement with higher early strength, higher ettringite content, and lower calcium silicate hydrate (C-S-H) content than PC. PC and BCSA cement concrete cylinders were broken at different ages in both uniaxial compression and TSS. It was found that BCSA had a similar TSS to both the ACI prediction and PC TSS, but the results require further testing for …

Young’S Modulus As A Measurement To Estimate Damage Related With Alkali-Silica Reaction In Concrete., Anazaria J. Ortega Gonzalez

Civil Engineering Undergraduate Honors Theses

The main purpose of this research is to compare two nondestructive methods to assess Alkali-Silica reaction (ASR) in concrete. Fifteen concrete prisms were cast using aggregates with different Alkali-Silica reactivity such as Jobe sand and Van Buren sand. The change in strain, shear wave velocity and Young’s modulus were determined according to ASTM C129 and ASTM C215, respectively. This data was collected by Dillon K Self, who determined that the shear wave velocity and strain are inversely proportional. However, when single cracking in the concrete specimen transition to map cracking, the shear wave velocity dropped significantly, whereas the strain value …

Utilizing The Hvsr Second Peak For Surface Wave Inversions In The Mississippi Embayment, Ashraf Kamal Himel

Graduate Theses and Dissertations

Ambient noise data from 24 sites within the Mississippi Embayment were analyzed to estimate the fundamental frequency using the horizontal to vertical spectral ratio (HVSR) method. The fundamental frequency ranged from 0.17 to 3.43 Hz for the tested sites. At seventeen of the sites, a second higher frequency HVSR peak, which ranged from 0.617 Hz to 2.154 Hz, was observed in addition to the fundamental HVSR peak. The second peak frequency in the HVSR curve has been attributed by previous researchers as either an odd harmonic of the fundamental peak or a shallow impedance contrast from the Memphis sand layer …

Examining The Use Of Idealized Granular Material In Validated Dem Simulations, Anjana Thoroppady Kittu

Graduate Theses and Dissertations

Discrete element method (DEM) modeling, is becoming widely used for understanding the micro-mechanical behavior of granular materials at the particle level. This dissertation presents important considerations regarding the experimental boundary conditions and idealized granular materials used in DEM validations.

A common issue in DEM validation studies for direct shear and direct simple shear is selecting top and bottom cap boundary conditions that allow for shear transmission while also being efficiently modeled in the DEM simulations. While the traditional grid boundary types used in the laboratory can be replicated in the numerical models, researchers have also used fixed-particle boundaries, sawtooth boundaries, …

Utilizing 3d Printed Analogue Soils To Investigate Specimen Size Effects In Triaxial Testing, Claire Louise Stewart

Graduate Theses and Dissertations

Triaxial testing is one of the fundamental laboratory tests used in geotechnical engineering to determine strength parameters, such as shear strength and friction angle. Investigating the minimum representative elementary volume (REV) can verify the independence of size effects on strength parameters and ensure that the scaled laboratory tests results are consistent, repeatable, and representative of field conditions. Although, REV has been studied for many applications, there is disagreement within geotechnical engineering of a minimum particle diameter to specimen diameter to minimize the size effects related to the REV in consolidated drained (CD) triaxial tests. This research study compared the strength …

Controlling Relative Humidity Using Glycerin, Juan Martinez

Civil Engineering Undergraduate Honors Theses

A series of tests were conducted to control relative humidity (RH) using a bubbler system that contained a series of glass jars and glass vials filled with different concentrations of glycerin. The relative humidity within the glass jars was measured. The total time interval for each laboratory test was 48 hours. During the first 24 hours a pump was used to bubble air through the glycerin solution. During the second 24 hours, the pump was turned off, and the RH within the system was monitored within the closed system. Target RH measurements from 100% to a 0% were obtained. The …

Evaluation Of A Centrifuge Consolidation Technique To Determine The Effects Of Temperature And Time On Kaolinite Properties, Esteban Miranda Pinzon

Civil Engineering Undergraduate Honors Theses

Abstract

The effects of time and temperature on the moisture content and unit weight profiles, as developed during a centrifuge consolidation process, were observed during the research program that is described herein. Specifically, a Beckman-Coulter Model J6-MI centrifuge with a six-place JS-4.2A swinging bucket rotor was utilized to consolidate kaolinite slurry samples. The consolidation procedure utilized specially designed slurry consolidometers, made from acrylic tubes with inside diameters of 2.63 inches (6.67 cm) and heights of 5.13 inches (13.04 cm). The tested kaolinite slurry samples were created by mixing 400 grams of dry kaolinite clay powder with 200 grams of de-aired …