Geotechnical Engineering Commons^™

Amplification Of Earthquake Ground Motions In Washington, Dc, And Implications For Hazard Assessments In Central And Eastern North America, Thomas L. Pratt, J. Wright Horton Jr., Jessica Munoz, Susan E. Hough, Martin C. Chapman, C. Guney Olgun

C. Guney Olgun

The extent of damage in Washington, DC, from the 2011 M_W 5.8 Mineral, VA, earthquake was surprising for an epicenter 130 km away; U.S. Geological Survey “Did-You-Feel-It” reports suggest that Atlantic Coastal Plain and other unconsolidated sediments amplified ground motions in the city. We measure this amplification relative to bedrock sites using earthquake signals recorded on a temporary seismometer array. The spectral ratios show strong amplification in the 0.7 to 4 Hz frequency range for sites on sediments. This range overlaps with resonant frequencies of buildings in the city as inferred from their heights, suggesting amplification ...

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 ...

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 ...

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

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 ...

Evaluation Of Synthetic Cpt And Soil Boring Data By Various Spatial Interpolation Techniques, Md Habibur Rahman

LSU Master's Theses

In order to incorporate the influence of collected in-situ data, the spatial correlation between the data and the foundation needs to be explored. However, risk and uncertainty are the characteristics of the soil that cannot be eliminated. Statistical information of the soil property can be estimated from available field data obtained from testing at discrete locations across the site. In this research, several well-established spatial interpolation methods like ordinary kriging (OK), simple kriging (SK), inverse distance weight (IDW), spline, natural neighbor (NaN) and universal kriging (UK) were incorporated to evaluate the best method. Six CPT (Cone penetration test) (Tip Resistance ...

Development Of Environmentally-Friendly Stabilization Methods For Transportation Infrastructure Based On Geopolymers, Miladin Radovic, Anand Puppala

Publications

Geopolymers (GPs) have received much attention as an eco-friendly and sustainable alternative to conventional chemical additives, since they can be processed at room temperatures from aqueous solutions by utilizing waste materials (e.g. fly ash) or abundant natural sources (e.g. clay). A collaborative research study is carried out by teams from Texas A&M University (TAMU) and University of Texas at Arlington (UTA) to investigate the effectiveness of GPs for stabilizing base and subgrade materials by considering the strength and shrink-swell characteristics. Two types of clay, obtained from the North Dallas area, were mixed with a potassium-based GP synthesized ...

Prediction And Rehabilitation Of Highway Embankment Slope Failures In Changing Climate, Navid Jafari, Anand Puppala

Publications

Highway slopes constructed with clayey soil are prone to desiccation cracks due to wetting and drying weather cycle, which allows greater moisture infiltration into the embankment from precipitation. Fissures formed due to extended wetting and drying cycles allow water to seep deeper into the soil than surficial wetting and increase the water content. This increases the moisture content in the soil and results in reduction in shear strength to the fully softened strength. On the other hand, development of desiccation cracks and reduction of the soil matric suction ultimately result in higher hydraulic conductivity value which causes development of higher ...

Field Instrumentations And Numerical Analysis Of Geosynthetic Reinforced Soil – Integrated Bridge System (Grs-Ibs), Allam Ardah

LSU Doctoral Dissertations

Geosynthetic reinforced soil (GRS) is a special soil with geosynthetic fabric closely stacked in layers as soil stabilization and considered an alternative design method to the conventional bridge support technology. In this research study, a field case study of Maree Michel bridge, which is located in Route LA 91 Vermilion Parish in Louisiana, was instrumented with six different types of instrumentations to monitor the performance of GRS-IBS bridge abutment and to develop 2D and 3D finite element models. The instrumentations include Shape Acceleration Array (SAA), earth pressure cells, strain gauges, piezometers, and thermocouples. Additionally, surveying was conducted at the bridge ...

Physical Modeling Of Flow Nets In Groundwater And Determination Of Hydraulic Conductivity, Hannah Nicholas, Moses Karakouzian

AANAPISI Poster Presentations

The goal of this study is to physically model the paths that water particles take through soil, and estimate hydraulic conductivity for several soil configurations. Water paths, or flow lines, are shown by injecting dye into sand contained in a rectangular acrylic glass tank with a vertical barrier in the center; water is poured on one side of the tank and a pump is used to maintain constant head loss. If flow lines are formed, a flow net is to be drawn using photos of the tank and hydraulic conductivity is to be calculated.

This project consists of four phases ...

Coir Fiber Reinforced Concrete, Jose De La Serna, Moses Karakouzian

AANAPISI Poster Presentations

This poster exhibits the testing and research done on general Portland Cement Concrete with the addition of coir (coconut) fibers as reinforcement. Using the fundamental constituents of cement (water, cement, fine and coarse aggregate) and processed coir fiber, concrete specimens were batched to test for compressive and flexural strengths (per appropriate ASTM standards). Cylindrical and rectangular beam specimens were subjected to loadings until failure occurred. The capacity and modes of failures of the specimens were observed. It was determined that:

• The addition of processed coir fibers decreases the overall strength of general Portland Cement Concrete. • The tested concrete’s mode ...

Evaluation Of Undrained Shear Strength And Soil Classification From Cone Penetration Test, Md Imran Hossain

LSU Master's Theses

The in-situ cone and piezocone penetration tests (CPT, PCPT) has been widely used by the geotechnical engineering community for subsurface soil characterization and classification, and for the evaluation of many engineering soil properties, such as undrained shear strength (s_u), unit weight (γ), constrained modulus (M), coefficient of consolidation (c_v), and stress history (OCR). The objective of this research study was to estimate the undrained shear strength of clayey soil using CPT/PCPT data in addition to some soil boring log data. At the same time, soil classification charts/methods based on CPT/PCPT were investigated and modified. For ...

Evaluation Of Site Variability And Its Application In Design, Abu Hakim Muhammad Hasan Faisal

LSU Master's Theses

Geotechnical characterization has an important role in engineering geology as well as in implementation of any project. There are several variables and uncertainties involved in characterizing a project site. Four different sources of uncertainties represent the characterization of geotechnical variability, which include spatial variability, measurement error, statistical error and model bias. Spatial variability is expressed in terms of the mean, variance, and scale of fluctuation. Several statistical techniques such as the Gauge R & R, which includes X-Bar/R and ANOVA, and the Second Moment can be applied to compute site variability in terms of the coefficient of variations. Measurement error ...

Seismic Response Of Columnar Reinforced Ground, C. Guney Olgun

C. Guney Olgun

Ground improvement using stiff columnar reinforcement, such as stone, jet-grout and soil-mix columns, is commonly used for mitigation of seismic damage in weak ground. Seismic shear stress reduction in the reinforced soil mass is often counted on for reducing liquefaction potential. Current design methods assume composite behavior of the reinforced soil, where the shear stress reduction is based on the ratio of the columnar stiffness relative to the soil as well as the area replacement ratio. This implicitly assumes that the stiff columns will deform in pure shear along with the surrounding soft soil. Three dimensional dynamic finite element analyses ...

Field Evidence And Laboratory Testing Of The Cyclic Vulnerability Of Fine-Grained Soils During The 1999 Kocaeli Earthquake, C. Guney Olgun, James R. Martin Ii, Atila Sezen

C. Guney Olgun

Significant earthquake-induced settlements occurred in saturated fine-grained soils at the Carrefour Shopping Center in Turkey during the 1999 Kocaeli Earthquake (M=7.4). Most of the settlement was due to the undrained cyclic failure of silt/clay (ML/CL) and highplasticity clay (CH) strata within the subsoil profile. Each suffered about 1% vertical strain. Extensive laboratory testing on undisturbed samples from these silty and clayey strata has been performed to investigate this behavior. The laboratory testing included monotonic and cyclic simple shear tests, triaxial tests and conventional 1-D consolidation tests. Considerable pore pressure increases have been measured during cyclic simple ...

Seismic Response Of Columnar Reinforced Ground, C. Guney Olgun

C. Guney Olgun

Ground improvement using stiff columnar reinforcement, such as stone, jet-grout and soil-mix columns, is commonly used for mitigation of seismic damage in weak ground. Seismic shear stress reduction in the reinforced soil mass is often counted on for reducing liquefaction potential. Current design methods assume composite behavior of the reinforced soil, where the shear stress reduction is based on the ratio of the columnar stiffness relative to the soil as well as the area replacement ratio. This implicitly assumes that the stiff columns will deform in pure shear along with the surrounding soft soil. Three dimensional dynamic finite element analyses ...

Seismic Performance Of Soil-Mix Panel Reinforced Ground, C. Guney Olgun, James R. Martin Ii

C. Guney Olgun

Ground reinforcement methods such as stone columns, jet grouting, and soil mixing are commonly used to improve subsoil conditions for seismic mitigation. In most cases, the purpose of this improvement is for foundation support and/or liquefaction mitigation. Additional benefits of the improvement, such as possible reduction in seismic ground motions, are not explicitly considered in NEHRP/IBC code provisions for establishing site classification and seismic design motions. Such reductions, if present, can have significant payoff. Reduced seismic loads on the super structure result in lower seismic design levels and reduced construction costs. It is conceivable that the cost of ...

Numerical Modeling Of Columnar Reinforced Ground 1999 Kocaeli Earthquake Case History, C. Guney Olgun, James R. Martin Ii

C. Guney Olgun

The Kocaeli Earthquake (M=7.4) struck Turkey on August 17, 1999 and caused significant damage along Izmit Bay. Following the earthquake, the authors investigated the field performance at improved soil sites. Of particular interest was the Carrefour Shopping Center that was under construction during the earthquake. The reclaimed site is underlain by strata of saturated soft clays, silts, and liquefiable loose sands. Small-diameter jet-grout columns had been installed at close spacings to reduce settlements and prevent liquefaction-related damage beneath footings and mats. Nonlinear dynamic three-dimensional finite element analyses were conducted to model the reinforced ground at Carrefour. The results ...

Liquefaction Potential Of Railway Embankments, Miguel A. Pando, C. Guney Olgun, James R. Martin Ii

C. Guney Olgun

This paper presents an overview of the nature of train-induced vibrations and discusses the liquefaction potential of railway embankments under such low-level vibrations. The paper also presents the results of static and dynamic finite difference numerical analyses performed for a simple railway embankment geometry. The liquefaction potential for the railway embankment foundation was estimated using the results corn FLAC numerical analyses, as well as a cyclic shear stress liquefaction resistance approach using a modified cyclic resistance ratio curve. Liquefaction of railway embankment foundations was found to be possible. However, based on the majority of reported failures the liquefaction potential remains ...

Field Evidence And Laboratory Testing Of The Cyclic Vulnerability Of Fine-Grained Soils During The 1999 Kocaeli Earthquake, C. Guney Olgun, James R. Martin Ii, Atila Sezen

C. Guney Olgun

Significant earthquake-induced settlements occurred in saturated fine-grained soils at the Carrefour Shopping Center in Turkey during the 1999 Kocaeli Earthquake (M=7.4). Most of the settlement was due to the undrained cyclic failure of silt/clay (ML/CL) and highplasticity clay (CH) strata within the subsoil profile. Each suffered about 1% vertical strain. Extensive laboratory testing on undisturbed samples from these silty and clayey strata has been performed to investigate this behavior. The laboratory testing included monotonic and cyclic simple shear tests, triaxial tests and conventional 1-D consolidation tests. Considerable pore pressure increases have been measured during cyclic simple ...

My Catalyst, Gabrielle Gambino Lyon

Celebration of Learning

Over the course of my internship and shadow program with Pepper Lawson Construction and Ziegler Cooper Architects, I was able to explore the various career paths involved in the design, construction, and civil engineering fields. My work on the construction site of a high-rise apartment building located in the heart of Houston, TX allowed me first-hand experience working and learning alongside project engineers, contractors, building developers, and the construction team.

This project was the perfect confluence of my main areas of interest: structural, mechanical, civil, and environmental engineering, as well as architecture. My daily work consisted of on-site walk throughs ...