Geotechnical Engineering Commons^™

Input Parameters In Discrete Element Modeling, Seyedali Yousefi

Civil Engineering ETDs

The discrete element method (DEM) is employed to study complex behaviors of particulate media. Input parameters may greatly affect the response of DEM models and should therefore be selected carefully. Scaling techniques are employed to enlarge prohibitively small time-steps. To study these techniques, dimensionless input parameters were defined. Responses of models in the dimensionless scale were invariant with choice of density, elastic modulus, and characteristic length if the dimensionless parameters were kept constant. Hence, density scaling is equivalent to use of a higher strain-rate, and stiffness scaling results in a higher strain-rate and an elevated stress state in the dimensionless …

Lucidpipe™ Power System, Purdue Ect Team

ECT Fact Sheets Archive

In most gravity fed water transmission pipelines, it is desired to reduce excess pressure head to prevent undue strain on a pipeline and lower the incidence of leaks. Normally this is done with pressure reducing valves that essentially burn off this excess pressure as heat. The LucidPipe™ system converts it to low cost electricity thereby removing unwanted pressure and generating energy at the same time - energy that can be put used behind the grid or put back on the grid. The LucidPipe™ system extracts a small percentage of pressure head providing nearly invisible operation allowing water operators to fulfill …

Soil Moduli Obtained From A Back Pressure Constant Rate Of Strain Bender Element Consolidation Apparatus, Yi Zhao

Graduate Theses and Dissertations

A back-pressure saturated, constant-rate-of-strain consolidation device was modified to incorporate bender elements (BP-CRS-BE) and thus allowed for shear wave measurements during consolidation tests. This newly fabricated system has many advantages over other previous or current devices: 1) it can be utilized not only for laboratory prepared soil samples but also for field sampled soils such as Shelby tube samples, and 2) continuous compression curves, and continuous values of vertical hydraulic conductivity and coefficient of consolidation can be acquired with a significant reduction in testing time. Soil modulus values such as shear modulus and constrained modulus are also able to be …

Geotechnical Properties Of The Travis Peak (Hosston) Formation In East Texas: A Compressive And Tensile Strength Analysis Using Regression Analysis., Pawan Kakarla

Electronic Theses and Dissertations

The estimation of rock mass strength is a key parameter in geotechnical engineering which is used in the design of geotechnical structures like tunnels, dams and slopes. Geotechnical engineering is the branch of civil engineering which works on the principles of soil and rock mechanics to evaluate subsurface conditions, stability of slopes, foundations of structures and construction of earthworks. The main focus of this study was to calculate the strength of Lower Cretaceous Travis Peak Formation rocks of East Texas and to check the accuracy by comparing it with Regression analysis. The parameters which were used were the Uniaxial Compression …

Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub

Electronic Theses and Dissertations

The Delaware Basin of West Texas and southeastern New Mexico is the major western subdivision of the Permian Basin and a northern extension of the Chihuahuan Desert. The major evaporite unit within the Delaware Basin is the Castile Formation, which consists of gypsum/anhydrite and is highly susceptible to dissolution and karsting. Manifestations of karst within the Castile outcrop are abundant and include sinkholes, subsidence features and caves, both epigene and hypogene in origin.

Land reconnaissance surveys conducted during the summer of 2015 documented abundant karst landforms in close proximity to a major thoroughfare, RM 652, in Culberson County, Texas. 2D …

Effect Of Temperature On Deep Lined Circular Tunnels In Isotropic And Transversely Anisotropic Elastic Ground, Fei Tao

Open Access Theses

A tunnel is a passageway constructed through soil or rock. It is one of the most important underground structures and has been widely used in transportation. Much research has been done on tunnel performance and on the interaction between ground, excavation, liner installation and support. The work has provided a better understanding of the interplay that exists between deformations and stresses transferred from the ground to the support. Significant insight into the problem has been provided by closed-form analytical solutions. A number of analytical formulations have been obtained for underground openings and lined tunnels under different scenarios, namely shallow or …

Electromagnetically Induced Alteration Of Hydraulic Conductivity Of Coarse-Grained Soils For Geotechnical Applications, Rakesh Acharya

Boise State University Theses and Dissertations

Electromagnetic (EM) waves of various power levels and frequencies can be used to alter the hydraulic conductivity of soil with minimal heat generation. The result can lead to a number of potential applications such as contamination remediation and liquefaction mitigation. In this research, the possibility of radio-frequency (RF) waves’ effect on the excess pore-water pressure (EPWP) generation and hydraulic conductivity of coarse-grained soils has been investigated.

Impact tests were performed on glass beads to examine the effect on the generation of EPWP due to RF waves. These tests were performed on a rigid box made of Plexiglas. The impacts were …

Evaluating The Suitability Of Microbial Induced Calcite Precipitation Technique For Stabilizing Expansive Soils, Sikha Neupane

Boise State University Theses and Dissertations

Expansive soils, also known as swell-shrink soils have been a problem for civil infrastructures including roads and foundations from ancient times. The use of chemical additives such as cement and lime to stabilize expansive soils is a common practice among geotechnical engineers especially for lightly loaded structures. However, several occurrences of subgrade failures were observed after stabilizing with chemical additives hence engineers are in search of sustainable stabilization alternatives. Microbial Induced Calcite Precipitation (MICP) is gaining attention as an environmental friendly soil improvement technique. Several researchers have successfully tested its feasibility in mitigating liquefaction induced problems in sandy soils. This …

Determination Of Seismic Earth Pressures On Retaining Walls Through Finite Element Analysis, Michael Iannelli

Master's Theses

Seismic pressures on displacing or rigid retaining or basement walls have been derived based on the original work of Mononobe and Okabe, who used a shake table to calculate dynamic pressures of displacing retaining walls existing in cohesionless soils. Since this original work was done over eighty years ago, the results of Mononobe and Okabe, colloquially known as M-O theory, have been applied to different conditions, including non-displacing basement walls, as well as changes in soil properties. Since the original work of M-O, there have been numerous studies completed to verify the accuracy of the original calculation, most notably the …

Coupled Numerical Analysis Of Variations In The Capacity Of An Energy Pile In Clay Soil, Daniel Patrick Zimmerman

Boise State University Theses and Dissertations

Energy piles are an emerging alternative for the reduction of energy consumption to heat and cool buildings. The majority of the research to date focuses on thermodynamic properties or axial strain of piles. This paper concerns the effects of temperature fluctuation on the capacity of driven energy piles in clayey soils. Consolidation of clay (due to the dissipation of excess pore-water pressure in clay) surrounding piles affects the capacity of the pile (pile setup in clay). Reciprocally, it is reasonable to assume that heating and cooling periods will create or relax the excess pore-water pressure (EPWP) in clayey soils (due …

Evaluation Of Slope Stability Quantifying The Effect Of Vegetation, Roberto José Marín, Juan Pablo Osorio

Conference papers

The present study evaluates the shallow landslides susceptibility triggered by rainfall by means of multiple numerical simulations. The simulations integrate a transient rainfall infiltration model with an infinite slope stability model, both of them developed for unsaturated soils in a basin scale. TRIGRS’ infiltration model is used to calculate pore water pressure. The geotechnical model includes the evaluation of two parameters related to vegetation: root reinforcement and tree surcharge due to the weight of the vegetation. These simulations were carried out using multiple values of these parameters so that their behavior is analyzed for the topographic conditions of the watershed …

Guidance Index For Shallow Landslide Hazard Analysis, Cheila Cullen

Dissertations, Theses, and Capstone Projects

Rainfall-induced landslides are one of the most frequent hazards on slanted terrains. They lead to considerable economic losses and fatalities worldwide. Intense storms with high-intensity and long-duration rainfall have high potential to trigger rapidly moving soil masses due to changes in pore water pressure and seepage forces. Nevertheless, regardless of the intensity-duration of the rainfall, shallow landslides are influenced by antecedent soil moisture conditions. To the present day, no system exists that dynamically interrelates these two factors.

This work establishes a relationship between antecedent soil moisture and rainfall expressed in the form of a Shallow Landslide Index (SLI) at 1km …

Post-Liquefaction Residual Strength Assessment Of The Las Palmas, Chile Tailings Failure, Tristan Reyes Gebhart

Master's Theses

Assessment of post-liquefaction residual strength is needed for the development of empirically-based, predictive correlations for earthquake engineering design. Previous practice commonly assigned negligible strengths to liquefied materials for engineering analysis, producing overly-conservative designs. Increasingly available case history data, and improved analytical tools have allowed for more accurate and less overly-conservative estimation of soil residual strength, improving empirical predictive models. This study provides a new case history to the limited suite of (approximately 30) liquefaction failure case histories available for post-liquefaction in-situ strength predictive correlations.

This case history documents the Las Palmas gold mine tailings dam failure, resulting from seismic-induced liquefaction …

Membership Of Forum For Promotion Of Soil Dynamics In India, Shamsher Prakash

Forum for Promotion of Soil Dynamics in India

No abstract provided.

Minutes Of The Fourth Meeting Of The Forum For Promotion Of Soil Dynamics In India, Shamsher Prakash

Forum for Promotion of Soil Dynamics in India

No abstract provided.

Stochastic Modeling And Dem Simulation Of Granular Media Subsidence Due To Underground Activity, Rodrigo Borela Valente

Open Access Theses

Many communities around the world have been established in areas of ongoing, as well as ceased, underground mining activity. Ground movements induced by ore extraction methods and the collapse of abandoned cavities have long been recognized as a hazard to surface structures. A number of approaches have been proposed for the prediction of subsidence in underground mining regions, and their integration to Geographic Information Systems (GIS) can produce a powerful risk management tool. Nevertheless, this application is often limited by either a lack of generality or excessive computational cost of the methods available.

In this work, the stochastic subsidence model …

Soil-Bentonite Slurry Trench Cutoff Wall Closeout Report, Daniel Ruffing

NSF Soil-Bentonite Slurry Trench Cutoff Wall Documents

Assessment report of the construction of a soil-bentonite slurry wall including milestone dates, work description, and quality control.

Use Of Recycled Crushed Concrete (Rcc) Fines For Potential Soil Stabilization, Lindeman Mark, Varilek Brandon, Lieska Halsey, Rick Gloe, Maria Olomi

Nebraska Department of Transportation: Research Reports

This study evaluated the use of Recycled Crushed Concrete (RCC) Fines for potential soil stabilization. Soil stabilization is the enhancement of subgrade stability to improve the constructability of successive pavement layers. Use of RCC fines may not only provide less costly alternatives for subgrade stabilization, but their use may also alleviate landfill disposal challenges.

Correlating Interlaminar Fatigue Fracture Behavior To Nde Parameters In Carbon/Epoxy Composites Containing Voids And Delamination, Issa Hakim, Norbert Meyendorf, Steven L. Donaldson, René Laquai, David Walter, Bernd Müller, Paul Graja

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Carbon fiber composites have been increasingly used in aerospace, military, sports, automotive and other fields due to their excellent properties, including high specific strength, high specific modulus, corrosion resistance, fatigue resistance, and low thermal expansion coefficient. Delamination, or interlaminar fracture, is a serious failure mode leading to a loss in composite stiffness and strength. Manufacturing process defects such as voids degrade the fatigue life and delamination resistance of the composite. This study investigates the effect of voids on fatigue interlaminar fracture behavior of carbon fiber composites. Samples with different vacuum levels: 0%, 50% and 100% were fabricated by varying the …

Determination Of Non-Nuclear Alternative To The Nuclear Density Gauge Through Laboratory And Field Testing, Janine Abyad

Theses and Dissertations

Pavement performance is dependent on the compaction quality of unbound subgrade and base/subbase layers beneath flexible pavements. Pavement distresses can be linked to compaction defects within these layers. In current practice, the New Jersey Department of Transportation (NJDOT) utilizes the nuclear density gauge (NDG) for evaluating compaction quality based on minimum density requirements, typically 95% of the Proctor maximum dry density (MDD). However, there are concerns with using the NDG. The goal of this study was to replace the NDG with non-nuclear alternative method(s) as acceptance tools during field compaction. To achieve this, a laboratory procedure for compacting large samples …

Ncma Groundwater Model Using Usgs Modflow-2005/Pest, Brian Matthew Wallace

Master's Theses

A numerical model for the NCMA aquifer complex is presented. The objective of the study is to develop a numerical groundwater model for the NCMA aquifer system to enhance the understanding of subsurface groundwater flow. Infiltration, streamflow, pumping, and return flows are implemented to characterize the aquifer complex over time. The numerical model is calibrated to municipal and monitoring well data, average monthly water balances, and hydraulic contours. Transient aquifer inflows and outflows are assessed in the results of the study and are compared to balance terms from previous studies. The 2007 Todd Engineers Study subsurface inflows and outflows generate …

Validation Of An Internal Camera Based Volume Determination System For Triaxial Testing, Leah D. Miramontes

Civil Engineering Undergraduate Honors Theses

Accurate strain and volume measurements are critical to phase relationships and strength determination for saturated and unsaturated soils. In recent years, laboratory-based photographic techniques of monitoring soil specimens have become more common. These techniques have been used to reconstruct 3D models and to determine strain and volumetric changes of triaxial specimens. A new technique that utilized digital photographs of the soil specimen, captured from within a triaxial testing cell, was utilized. Photographs were processed using photogrammetry software to reconstruct 3D models of the soil specimens. By placing camera equipment within the cell, the technique eliminated the need to account for …

Full Depth Reclamation Of Aviation Pavement, Michael W. Buening

Purdue Road School

Full depth reclamation (FDR) has been utilized multiple times in recent years for airport and roadway pavement rehabilitation. The presentation will review FDR and its use as a treatment for aviation pavements.

Wildcat Bridge - I-65 Artesion Well/Geotechnical/Structural, Anne Rearick, Jeremy Hunter, Silas Nichols, Mir Zaheer

Purdue Road School

In this session we will discuss the emergency design and repair of the I-65 bridge over Wildcat Creek in Tippecanoe County during the summer of 2015 that closed I-65 northbound.

Storm Damage - Murphy's Law, Dale Sedler, Mark Bailey

Purdue Road School

Examination of a disastrous event that required 4 coinciding occurrences happening that individually would likely have resulted in minor or no damage.

Barometer Rising: The Cartagena Protocol On Biosafety As A Model For Holistic International Regulation Of Ocean Fertilization Projects And Other Forms Of Geoengineering, Matthew Hubbard

William & Mary Environmental Law and Policy Review

No abstract provided.

Full-Scale Shake Table Cyclic Simple Shear Testing Of Liquefiable Soil, Jasper Stanford Jacobs

Master's Theses

This research consists of full-scale shake table tests to investigate liquefaction of sandy soils. Consideration of the potential and consequences of liquefaction is critical to the performance of any structure built in locations of high seismicity underlain by saturated granular materials as it is the leading cause of damage associated with ground failure. In certain cases the financial losses associated with liquefaction can significantly impact the financial future of an entire region.

Most liquefaction triggering studies are performed in the field where liquefaction has been previously observed, or in tabletop laboratory testing. The study detailed herein is a controlled laboratory …

Late Morning Concurrent Sessions: Innovations In Aviation Technologies: Presentation: Relative Material Loss: A Methodology For Assessing Island Airport Steel Marine Bulkheads, Robert Ernsting, Constantine M. Koursaris

Aviation / Aeronautics / Aerospace International Research Conference

A July 2015 report from the Airports Council International – North America (ACI-NA) states “U.S. airports are long overdue for [a] major structural improvement projects. Most U.S. airports are aging, … and because of budgetary restrictions, they’re not aging well.”(Garcia and Clampet, 2015). The average US age is 40 years old with the youngest (Denver International) recently turning 20 years old. As airports continue to age, airport commissioners will struggle to find creative ways to either fund airport replacements or extend the service life of existing airport facilities (commonly referred to as service life extension projects or SLEP). Due to …

Underwater Explosion Energy Dissipation Near Waterborne Infrastructure, Paul R. Smith

Theses and Dissertations--Civil Engineering

Underwater explosions pose a significant threat to waterborne infrastructure though destructive pressure waves that can travel significant distances through the water. However, the use of bubble screens can attenuate the peak pressure and energy flux created by explosions to safe levels. This study investigates the prediction of pressure wave characteristics based on accumulated data, the damage potential of underwater explosions based on applied loads and effective material strength, and the bubble screen parameters required to prevent damage. The results were compiled to form a procedure for the design and implementation of a bubble screen the protection of waterborne infrastructure.

Enhancing The Strength Properties Of Fly Ash By Adding Waste Products, Alfred J. Susilo

Theses and Dissertations--Civil Engineering

For this study, the main material to be investigated is Class F fly ash that originates from the combustion of Appalachian coal. Alone, fly ash exhibits poor strength properties and is susceptible to liquefaction when subject to dynamic loading. This research is focused on investigating the effect of adding materials that would otherwise be considered as waste products to the fly ash. Materials to be considered include crumb rubber, shredded carpet and shredded paper. The benefits from this research are twofold. First, provide a method to stabilize fly ash. For large masses of fly ash such as those found at …