Geotechnical Engineering Commons^™

Development Of An Internal Camera-Based Volume Determination System For Triaxial Testing, Sean Elliott Salazar

Graduate Theses and Dissertations

Accurate measurement of axial, radial, and volumetric strain parameters are critical to the understanding of phase relationships and the constitutive behavior for saturated and unsaturated soils. The use of photographic monitoring techniques for laboratory-based measurement of these parameters have become common. A novel technique that utilized camera instrumentation located within the triaxial testing cell was developed and validated. By placing the instrumentation inside of the cell, instead of the instrumentation being located outside of the cell, the technique eliminated cumbersome corrections required to account for optical distortions due to 1) the refraction of light at the confining fluid-cell wall-atmosphere interfaces, …

Cost-Savings Of Implementing Site-Specific Ground Motion Response Analysis In Design Of Mississippi Embayment Bridges, Ethan Ryan Benton Baker

Graduate Theses and Dissertations

Deep dynamic site characterization and a site-specific ground motion response analysis (SSGMRA) were conducted for a bridge site in Monette, Arkansas. The SSGMRA indicated the design acceleration response spectrum determined using the American Association of State Highway and Transportation Officials (AASHTO) general seismic procedure could be reduced by 1/3 for the short period range due to attenuation of the short-period ground motions. The steel girder pile-bent bridge, originally designed using the AASHTO general seismic design procedure, was redesigned using the updated seismic demands estimated from SSGMRA. A cost-savings analysis was then conducted to determine the potential savings associated with conducting …

An Evaluation Of Borehole Hydraulic Conductivity Equations And Field Determined Soil Water Characteristic Curves, Johnathan Dale Blanchard

Graduate Theses and Dissertations

The methods utilized to determine the hydraulic conductivity of compacted clay liners (CCLs) are of importance for safe guarding the environment from landfill leachate. Therefore, the methods utilized in the analysis of the Two Stage Borehole (TSB) test, as described in the ASTM D6391-11 (Method A, B, and C) standard, were evaluated. Data from hydraulic conductivity tests, as performed on three test pads, were utilized to review the ASTM D6391-11 equations. Additionally, two test pads were instrumented with volumetric water content and soil water matric potential sensors to facilitate the determination of field-obtained soil water characteristic curves (SWCCs) and hydraulic …

Dem Study Of A Single Stone Column In A Clayey Stratum, Anibal Enrique Santos

Graduate Theses and Dissertations

Aggregate piers are an alternative ground improvement technique used for improving the bearing capacity and reducing the total and differential settlement of foundations supported on compressible soils. The piers are composed of a series of vibrationally compacted aggregate lifts from a desired depth up to the finished foundation level. The shear strength of the coarse-grained material comprising an aggregate pier is defined by its internal friction angle. There are several factors affecting the friction angle of the granular material that include: confining stress, particle shape, relative density and particle distribution (gradation). These factors are not directly considered in the design …

Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard

Electronic Theses and Dissertations

ABSTRACT

Differential dissolution of gypsum karst within the Delaware Basin poses a significant threat to infrastructure that society depends on. The study area is located in Culberson County, Texas and traverses a distance of approximately 54 kilometers along RM 652 within the Gypsum Plain which is situated on the northern margin of the Chihuahua Desert and includes outcrops of Castile and Rustler strata that host karst geohazards. Regions of karst geohazard potential have been physically surveyed proximal to the study area in evaporites throughout the Castile Formation outcrop; minimal hazards, in comparison to the Castile Formation, have been documented in …

Evaluating The Effectiveness Of A Hybrid Geosynthetic Reinforcement System To Mitigate Differential Heave On Flexible Pavement Due To Expansive Subgrades, Mir Md. Tamim

Boise State University Theses and Dissertations

Transportation industries encounter substantial challenges with respect to ride quality and serviceability when they deal with expansive soils underneath roadway structures. These soils exhibit swell-shrink behavior with moisture variations, which cause surficial heaving on the pavement structure and cost billions of dollars for the maintenance of pavements. For the past four decades, a particular stretch of US-95 (Oregon line to Elephant Butte) exhibited recurrent swelling distresses due to the underlying expansive soils. Despite remedial measures that exhibited satisfactory results for most of the sections, recurrent damage still continued in few sections. Further research indicated that the problematic soils were located …

The Role Of Soil Stiffness In Reverse Fault Rupture Propagation, Moises I. Buelna

Master's Theses

A nonlinear Mohr-Coulomb constitutive model with a strain dependent yield surface and non-associated flow was employed to study the plastic soil properties which affect the rate of surface fault rupture propagation in reverse events. These numerical simulations show a trend for soils with higher stiffness to have a higher rate of rupture propagation. Additionally the study shows the effects of strain softening and hardening on the rate of rupture propagation. Soils which strain harden exhibiting ductile behavior typically require more basal offset to rupture to the surface than soils which strain soften exhibiting brittle behavior. These results agree with our …

Numerical Evaluation Of The Lateral Behavior Of Vertical And Battered Pile Group Foundations Using 3-D Finite Element Modeling, Ahmad Souri

LSU Doctoral Dissertations

The design of pile foundations to resist lateral loads is essential in offshore structures and bridge foundations. The lateral behavior of piles has been studied in the past by experimental investigations coupled with analytical and numerical methods. The problem is complex due to the nonlinearities from soil behavior, gap formation, and pile-soil-pile interaction in pile groups (or the group effect). In this work, the finite element (FE) modeling was used to study the lateral behavior of pile groups. The FE method is robust and allows incorporating the necessary aspects for studying the behavior of pile groups. The nonlinear material behavior …

Modelling Tree Contribution In Susceptibility Analysis Of Shallow Llandslides, Roberto José Marín Sánchez, Juan Pablo Osorio

Articles

In this paper an assessment of shallow landslides susceptibility in a tropical and mountainous terrain is made. A method that allows to model slope stability over large areas is used. Tree contribution is quantified by means of three parameters: rainfall interception, root reinforcement and tree surcharge. A rainfall interception model is used to determine the rain available for infiltration and its temporal distribution during the simulation. The hydrological models included in TRIGRS are described, which allows to determine the pore water pressure depending on the initial conditions. This pore water pressure is used in the revised infinite slope stability model, …

An Analysis Of The Optimal Mix Of Global Energy Resources And The Potential Need For Geoengineering Using The Ceagom Model, John George Anasis, M. A. K. Khalil, George G. Lendaris, Christopher L. Butenhoff, Randall Bluffstone

Complex Systems Faculty Publications and Presentations

Humanity faces tremendous challenges as a result of anthropogenic climate change caused by greenhouse gas emissions. The mix of resources deployed in order to meet the energy needs of a growing global population is key to addressing the climate change issue. The goal of this research is to examine the optimal mix of energy resources that should be deployed to meet a forecast global energy demand while still meeting desired climate targets. The research includes the unique feature of examining the role that geoengineering can play in this optimization. The results show that some form of geoengineering is likely to …

Datumate, Purdue Ect Team

ECT Fact Sheets Archive

Datumate is digitally transforming civil engineering processes used in construction, surveying and infrastructure inspection markets with fully automated, highly precise, cost effective and safe tools. It utilizes state-of-the-art image processing and advanced drones and camera technologies dramatically reducing the amount of time surveying crews spend in the field, speeding up construction progress checks and shortening infrastructure inspection duration, while maintaining survey grade accuracy. The intuitive, simple and automated solutions increase productivity by saving field and office time in civil engineering and inspection projects of roads, intersections, stockpile volumes, topography, piping, industrial facilities, bridges, property surveys, building facades, railways, cellular infrastructure …

Evaluating The Liquefaction And Reliquefaction Behavior Of A Carbonate Sand, Abouzar Sadrekarimi

Civil and Environmental Engineering Presentations

Despite extensive amount of research on liquefaction analysis of sands, reliquefaction behavior and cyclic liquefaction resistance of cohesionless soils under a repeated cyclic load have not received the same amount of consideration. This is important as most soil deposits in high seismic areas have been subjected to repeated number of earthquakes. This paper presents series of laboratory cyclic simple shear tests on specimens of a local carbonate sand from London, Ontario. Sand specimens are reconstituted at relative densities of 25%, 45%, and 65% and subjected to effective vertical stresses of 50, 100, 200, 400, and 600 kPa. Reconstituted samples are …

Reliability Analysis Of Active Earth Pressure For Cantilever Walls On Mudflows And Residual Soils Of The Aburrá Valley, Juan David Castro, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

According to the variability of the local geology of the Aburrá Valley, two geological strata with similar grain size distribution were analyzed. The geologies are composed of mudflows and residual soils from the San Diego stock in the Poblado neighborhood. These soils show a similar mechanical behavior in relation to the number of blows of the standard penetration test SPT. The analysis was carried out by reliability methods for the determination of the active earth pressure for the geotechnical design of a cantilever walls. The analysis consists in the variation of the height of the retaining wall between 1 and …

Geology Influence In The Slope Stability Analysis By Limit Equilibrium, Finite Elements And Random Finite Elements Methods, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

Slope stability analyzes correspond to the evaluation of the safety factors commonly performed through the limit equilibrium and finite element methods. Due to the uncertainty of the geotechnical parameters, different statistical methods have emerged such as the limit equilibrium combined with the Monte Carlo simulation method and the random finite elements, which have been widely accepted in recent years. Normally, these analyzes are not performed taking into account the geological influence on the geotechnical properties, so in this work we proceed with the comparison of several geometrical typologies of slopes for mudflows and a residual soils of the Stock San …

Diagenesis And Formation Stress In Fracture Conductivity Of Shaly Rocks; Experimental-Modelling Approach In Co2-Rock Interactions, Abiola Olukola Olabode

LSU Doctoral Dissertations

In large scale subsurface injection of carbon dioxide (CO₂) as obtainable in carbon sequestration programs and in environmentally friendly hydraulic fracturing processes (using supercritical CO₂), long term rock-fluid interaction can affect reservoir and seal rocks properties which are essential in monitoring the progress of these operations. The mineralogical components of sedimentary rocks are geochemically active particularly under enormous earth stresses, which generate high pressure and temperature conditions in the subsurface. While geomechanical properties such as rock stiffness, Poisson’s ratio and fracture geometry largely govern fluid flow characteristics in deep fractured formations, the effect of mineralization can …

Aluminosilicate Dissolution And Silicate Carbonation During Geologic Co2 Sequestration, Yujia Min

McKelvey School of Engineering Graduate Student Theses & Dissertations

Geologic CO2 sequestration (GCS) is considered a promising method to reduce anthropogenic CO2 emission. Assessing the supercritical CO2 (scCO2)¬–gas or liquid phase water (g, l)–mineral interactions is critical to evaluating the viability of GCS processes. This work contributes to our understanding of geochemical reactions at CO2¬–water (g, l)–mineral interfaces, by investigating the dissolution of aluminosilicates in CO2-acidified water (l). Plagioclase and biotite were chosen as model minerals in reservoir rock and caprock, respectively. To elucidate the effects of brine chemistry, first, the influences of cations in brine including Na, Ca, and K, have been investigated. In addition to the cations, …

Technology To Manufacture Oriented Pvc (Pvc-O) Pipes, Purdue Ect Team

ECT Fact Sheets Archive

The development of Molecor´s technology, which is based on the application of a Molecular Orientation process, has delivered a significant turning point in the pipelines sector. With this technological development, the company has begun to manufacture TOM® PVC-O pipes, the most eco-friendly pipes on the market. The Molecor technology enabled eradicating many of the existing disadvantages of thermoplastic pipes.

This technology delivers a clear objective; to provide the water industry with a solution for pipes carrying pressurized water in an environmentally friendly, yet cost efficient manner. This also extends a service life compared to pipeline materials currently in use.

The …

Viscoelastic Analysis And Fatigue Characterization Of Bituminous Materials In Two Length Scales Under The Influence Of Aging, Santosh Reddy Kommidi

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

Fatigue cracking in asphalt concrete (AC) is of immense importance to pavement design and analysis because it is one of the most important forms of distress that can lead to structural failure in pavement. Once started, these types of cracks can be combined with other environmental factors leading to detrimental effects such as faster rates of pavement deterioration and shortened pavement life and functionality.

Currently AASHTO TP101, also known as linear amplitude sweep (LAS) specification, is being widely used to evaluate the ability of an asphalt binder to resist fatigue. The LAS method, although mechanistic in its approach, has certain …

Soil-Structure Interaction Effects On The Seismic Response Of Low-Rise Eccentrically Braced Frames, Luis Gerardo Buitrago Goyez

Graduate Theses and Dissertations

The importance of soil-structure interaction (SSI) effects on the seismic response of buildings has been long recognized and has been researched for over 40 years. However, SSI analysis has only been applied in a few building projects because the fixed base condition is considered to provide a conservative estimation for the response of buildings under seismic loads. This assumption of a fixed base condition adopted by practitioners is not always conservative or cost-effective, especially for rigid buildings over soft soils. Additionally, for the case of ductile steel frames with eccentric configurations, the influence of SSI on their seismic performance has …

Laboratory Resistivity Measurements For Soil Characterization, Behdad Mofarraj Kouchaki

Graduate Theses and Dissertations

Field based electrical resistivity measurements, such as electrical resistivity tomography (ERT) and capacitively coupled resistivity (CCR), are geophysical methods that offer a non-destructive and rapid means to collect continuous data. As such, ERT and CCR are becoming increasingly popular tools for geotechnical engineers; however, it is challenging to derive geotechnical information such as soil type, density, and water content from the data. A laboratory geophysical investigation was carried out to gain a better understanding of the parameters that affect the electrical resistivity of soils and devise a relationship between resistivity and soil type or classification. In this study, a soil …