Geotechnical Engineering Commons^™

Liquefaction Case Histories From Oceano, California During The 2003 San Simeon Earthquake, Hayden Brake

Master's Theses

On December 22nd, 2003, the Mw=6.5 San Simeon earthquake occurred 12 kilometers east of San Simeon, California, causing damage to buildings, roads, and other infrastructure throughout the central coast. The community of Oceano, 80 kilometers southeast of the epicenter, experienced damage to foundations, roads, and utilities due to liquefaction and lateral spreading. The unique geologic environment in Oceano caused a local amplification of ground motions, liquefaction, and lateral spreading. This study entailed developing ten liquefaction case histories from Oceano during the 2003 San Simeon earthquake. Four of the ten case histories are liquefaction cases and six are non-liquefaction cases, with …

Understanding The Hydromechanical Effects Of Extreme Events To Improve The Performance Of Infrastructure Foundations, Siddharth Marathe

All Dissertations

Extreme hydroclimatic events like heavy rainfall, flooding, and prolonged drought can potentially cause the failure of infrastructure foundations, leading to socio-economic losses. The objective of this dissertation is to understand the deformation and bearing capacity behavior of drilled shafts subjected to extreme hydroclimatic events, including heavy rainfall, prolonged drought, and earthquake. The Finite Element Method (FEM) results show that during rainfall, the drilled shaft settled caused by a decrease in the porewater pressure in the sand leading to a decrease in the axial bearing capacity. The axial force variation from an experimental investigation showed good agreement with the FEM. The …

A Predictive Modeling Approach For Assessing Seismic Soil Liquefaction Potential Using Cpt Data, Jonathan Paul Schmidt

Master's Theses

Soil liquefaction, or loss of strength due to excess pore water pressures generated during dynamic loading, is a main cause of damage during earthquakes. When a soil liquefies (referred to as triggering), it may lose its ability to support overlying structures, deform vertically or laterally, or cause buoyant uplift of buried utilities. Empirical liquefaction models, used to predict liquefaction potential based upon in-situ soil index property measurements and anticipated level of seismic loading, are the standard of practice for assessing liquefaction triggering. However, many current models do not incorporate predictor variable uncertainty or do so in a limited fashion. Additionally, …

Measuring Liquefied Residual Strength Using Full-Scale Shake Table Cyclic Simple Shear Tests, Taylor R. Honnette

Master's Theses

This research consists of full-scale cyclic shake table tests to investigate liquefied residual strength of #2/16 Monterey Sand. A simple shear testing apparatus was mounted to a full-scale one-dimensional shake table to mimic a confined layer of saturated sand subjected to strong ground motions. Testing was performed at the Parson’s Geotechnical and Earthquake Laboratory at California Polytechnic State University, San Luis Obispo. T-bar penetrometer pullout tests were used to measure residual strength of the liquefied soil during cyclic testing. Cone Penetration Testing (CPT) was performed on the soil specimen throughout testing to relate the laboratory specimen to field index test …

Liquefaction-Induced Dragload And/Or Downdrag On Deep Foundations Within The New Madrid Seismic Zone, Ishimwe Elvis

Graduate Theses and Dissertations

Deep foundation elements are typically used to transfer structural loads for multi-story buildings and large-span bridges to a competent soil layer when 1) the soil close to the ground surface has no sufficient bearing capacity, and when 2) liquefiable soils are encountered. The majority of the bridges constructed within seismic zones rely upon the stability of earthen embankments and deep foundation that are installed above or within liquefiable soil deposits. Despite large factor of safety values or different load and resistance factors being used to adequately design deep foundations within seismic areas, soil liquefaction may cause extensive damage to the …

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 …

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 …

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 …

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 …

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 …

Estimating Field At-Rest Lateral Stress Coefficient And Liquefaction Resistance Of Aged Sands, Md Hossian

All Dissertations

Published results of laboratory tests to evaluate the influence of the at-rest lateral stress coefficient (K0) and the overconsoildation ratio (OCR) on liquefaction resistance of sands are reviewed in this dissertation. It is found that significant increase in liquefaction resistance can occur with high K0 and/or high OCR. A unique relationship between liquefaction resistance of isotropic and anisotropic normally consolidated sands exists based on the published laboratory data. Relationships between liquefaction resistance of overconsolidated sands and normally consolidated sands also have been shown in previous laboratory studies. Based on the previous studies, expressions for K0 and OCR correction factors (KK0 …

Predicting The Dynamic Behavior Of Coal Mine Tailings Using State-Of-Practice Geotechnical Field Methods, Ali Salehian

Theses and Dissertations--Civil Engineering

This study is focused on developing a method to predict the dynamic behavior of mine tailings dams under earthquake loading. Tailings dams are a by-product of coal mining and processing activities. Mine tailings impoundments are prone to instability and failure under seismic loading as a result of the mechanical behavior of the tailings. Due to the existence of potential seismic sources in close proximity to the coal mining regions in the United States, it is necessary to assess the post-earthquake stability of these tailings dams.

To develop the aforementioned methodology, 34 cyclic triaxial tests along with vane shear tests were …

Anisotropy And Its Relation To Liquefaction Resistance Of Granular Material, Isao Ishibashi, Omer F. Capar

Civil & Environmental Engineering Faculty Publications

This research establishes quantitative relationships between soil's anisotropy and liquefaction resistance for granular materials. Uniform medium density (D_r = 50%) sand specimens were prepared using three different sample preparation techniques (air pluviated (AP), moist tamped (NIT), and moist vibrated (MV)) to create different initial soil fabrics. Undrained cyclic triaxial tests were then performed to determine the liquefaction resistance of each soil specimen. On the same specimens in the triaxial cell, vertical and horizontal compression wave velocities and vertical shear wave velocity (V_s) were measured using piezoelectric bender elements. Anisotropic (transversely isotropic) elastic constants of the soil specimens were …

Pile Response Characteristics Of Liquefied Soil Layers In Shaking Table Tests Of A Large Scale Laminar Shear Box, Kaeko Yahata, Yasutsugu Suzuki, Hideki Funahara, Mutsuhiro Yoshizawa, Shuji Tamura, Kohji Tokimatsu

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

To better understand the causes of pile damages during earthquakes such as Hyogoken-Nanbu Earthquake, shaking table tests of soil-pile-structure interaction models were done using a large scale laminar shear box. Because the pile response is affected by both the ground motion and the structure's inertial forces, three models were test & a soil-pile model and two soil-pile-structure models. For the latter models, superstructures with long and short natural periods were tested separately. Through comparisons among the three cases, the influences on the pile response due to the inertial force of the superstructure for the long and short natural periods were …