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Seismic Microzonation Of The Texcoco Lake Area, Mexico, Luis Osorio Flores, Juan M. Mayoral Villa, Miguel P. Romo 2010 Instituto de Ingeniería, UNAM, Mexico

Seismic Microzonation Of The Texcoco Lake Area, Mexico, Luis Osorio Flores, Juan M. Mayoral Villa, Miguel P. Romo

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

This paper presents some of the most relevant results obtained from field, laboratory and analytical investigations aimed at characterizing the seismic environment prevailing at the Texcoco lake region, in the Valley of Mexico, with the goal of developing a microzonation. In particular, this study focuses on an area of 19.0 by 5.5 km2, which has been instrumented with four seismological stations: TXSO, TXS1, TXS2 and TXCH that have recorded ground motions for at least 15 years. Field investigations were conducted to define the subsoil conditions underneath each station. Dynamic testing in these high plasticity clays was carried out ...


Uniform Seismic Hazard Spectra Of Sanandaj, Iran, Kaveh Andisheh, Gholamreza Ghodrati Amiri, Seyed Ali Razavian Amrei 2010 University of Kurdistan, Iran

Uniform Seismic Hazard Spectra Of Sanandaj, Iran, Kaveh Andisheh, Gholamreza Ghodrati Amiri, Seyed Ali Razavian Amrei

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

This paper presents uniform seismic hazard spectra of Sanandaj city of Iran. Sanandaj is the administrative center of Kurdistan province, in which more than 500,000 people live in. A collected catalogue, containing both historical and instrumental events and covering the period from the 10th century BC to the year 2006, is used. Then seismic sources and The seismotectonic model of the considered region have been modeled within the radius of 200 km and recurrence relationship is established. After elimination of the aftershocks and foreshocks, the main earthquakes were taken into consideration to calculate the seismic parameters. For this purpose ...


Floatation Of Tunnel In Liquefiable Soil, S. C. Chian, S. P. G. Madabhushi 2010 University of Cambridge, U. K.

Floatation Of Tunnel In Liquefiable Soil, S. C. Chian, S. P. G. Madabhushi

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

Underground structures such as tunnels have a lower unit weight than the surrounding soil and are commonly deemed to be susceptible to floatation in liquefiable soil. In the process of floatation, the tunnel has to possess ample buoyancy force to shear and carry the overlying soil upwards. This is aided by soil liquefaction resulting from the increase in water pressure with number of earthquake loading cycles. With onset of liquefaction, effective stress decreases which lead to a reduction in the shear strength of soil, hence assisting the floatation of tunnel. Conversely, the total stress exerted by the overburden soil suppresses ...


Effective Stress Based Numerical Assessment Of Liquefaction-Induced Landslide At Degirmendere Cape, Izmit Bay During Kocaeli (Izmit)-Turkey Earthquake, Sevinc Unsal Oral, Kemal Önder Çetin 2010 Middle East Technical University, Turkey

Effective Stress Based Numerical Assessment Of Liquefaction-Induced Landslide At Degirmendere Cape, Izmit Bay During Kocaeli (Izmit)-Turkey Earthquake, Sevinc Unsal Oral, Kemal Önder Çetin

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

This paper presents the numerical assessment of seismically-induced slope instability observed at Degirmendere Cape, Izmit Bay during Kocaeli (Izmit)-Turkey earthquake. As is evident from the name of the site, Degirmendere Cape site is located at the north of Degirmendere, on a small intrusion into the Bay of Izmit. At Degirmendere Cape, there existed a municipality owned hotel and recreational areas. During the earthquake following slumping of the fill material, the site was unindated. All the recreational facilities as well as the municipality hotel were lost to Marmara Sea with its residents. Failure mechanism was attributed to fault rupture/seismically ...


Estimation Of Seismic Compression In Dry Soils Using The Cpt, P. K. Robertson, Lisheng Shao 2010 Gregg Drilling & Testing Inc., Signal Hill, CA

Estimation Of Seismic Compression In Dry Soils Using The Cpt, P. K. Robertson, Lisheng Shao

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

A popular method to evaluate earthquake induced settlements in dry sands is the approach proposed by Pradel (1998) which was based on standard penetration test (SPT) results and is only applicable to clean sands. A simple modification of the Pradel (1998) method is proposed based on cone penetration test (CPT) results and is extended to cover a wide range of unsaturated soils. A key parameter in the method by Pradel (1998) is the small strain shear modulus, Go, which can be estimated from the CPT or measured using the seismic CPT. The CPT can provide a continuous evaluation of ...


Examination Of Existing Dmt-Based Liquefaction Evaluation Methods By Side-By-Side Dmt And Cpt Tests, Gordon Tung-Chin Kung, Der-Her Lee, Pai-Hsiang Tsai 2010 National Cheng Kung University, Taiwan

Examination Of Existing Dmt-Based Liquefaction Evaluation Methods By Side-By-Side Dmt And Cpt Tests, Gordon Tung-Chin Kung, Der-Her Lee, Pai-Hsiang Tsai

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

This study employed the field measurements of flat dilatometer test (DMT) and cone penetration test (CPT) presented by a recent study (Tsai et al. 2009) and additional DMT and CPT data conducted in this present study to examine the existing DMT-based liquefaction evaluation methods. Specifically, the DMT and CPT were conducted side-by-side at each of six in-situ sites and thus it is feasible to incorporate those test results into validating the existing DMT-based methods such as Grasso and Maugeri (2006), Monaco et al. (2005), and Rena and Chameau (1991). The DMT parameter, horizontal stress index (KD), is used as ...


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 2010 Missouri University of Science and Technology

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

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

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 ...


Ground Motions And Liquefaction Potential, Roger L. Torres 2010 Bureau of Reclamation, Denver Federal Center, Lakewood, CO

Ground Motions And Liquefaction Potential, Roger L. Torres

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

Strong earthquakes have the potential to produce liquefaction of saturated and loose soils or to produce shear strength loss on sensitive clays, which may produce embankment failure with uncontrolled release of the reservoir. Earthfill Dam 101 has been classified as a high risk dam and this study attempts to determine the extent of the risk. It retains a 60,000 acre-feet reservoir with population downstream of the embankment. The analysis of the earthquake through a bracketed accelerogram provides insight into how the embankment will respond to the seismic loading and to the soils properties. In the case study, the peak ...


Liquefaction Countermeasure Technique By Using Logs For Carbon Storage Against Global Warming, Masaho Yoshida, Masakatsu Miyajima, Atsunori Numata 2010 Fukui National College of Technology, Japan

Liquefaction Countermeasure Technique By Using Logs For Carbon Storage Against Global Warming, Masaho Yoshida, Masakatsu Miyajima, Atsunori Numata

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

Global warming is one of the most serious problems which faced by civil engineers in this century. Because a wood can store carbon within itself, the utilization of wood in the construction projects may contribute to the mitigation of global warming. The technique of ground improvement by installing logs into loose sand layer as a countermeasure against soil liquefaction was proposed in this study. The logs had been used as pile foundation until 1950's in Japan. However, as the wood has high possibility of a decrease in strength by decay, the utilization of wood become minority in the construction ...


Liquefaction Mitigation Of Three Projects In California, Tom M. Farrell, Kyle Wallace, John Ho 2010 Farrell Design Build Cos., Inc., Placerville, CA

Liquefaction Mitigation Of Three Projects In California, Tom M. Farrell, Kyle Wallace, John Ho

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

Ground displacements resulting from earthquake-induced soil liquefaction and dynamic densification can cause moderate to severe structural damage during and after an earthquake. Geotechnical construction methods of mitigating these potential ground displacements include mass excavation and replacement with engineered fill, ground improvement such as soil mixing, jet grouting, compaction piers, vibro compaction, vibro stone columns, and deep dynamic compaction, or deep foundations such as driven piles. The ground improvement methods rely on altering the soil properties to resist the seismically-induced shear stresses and soil grain redistribution while deep foundation methods bypass liquefiable soil deposits to found in deeper competent soil or ...


Microscale Characterization Of Energy Dissipation Mechanisms During Liquefaction, Usama El Shamy, Christina Denissen 2010 Southern Methodist University, Dallas, TX

Microscale Characterization Of Energy Dissipation Mechanisms During Liquefaction, Usama El Shamy, Christina Denissen

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

This study utilizes the discrete element method (DEM) to present a microscopic energy monitoring approach to characterize energy dissipation mechanisms in seismically loaded soils. Numerical simulations were conducted on saturated deposits of granular particles subjected to seismic excitations, modeled using a transient fully-coupled continuum-fluid discrete-particle model. The onset of liquefaction is illustrated through macroscopic and microscopic response patterns. An in-depth look at the individual microscale energy components both before and after the onset of liquefaction is presented. Prior to liquefaction, energy is dissipated mainly through inter-particle sliding (friction energy), but after liquefaction particle-to-particle impact damping also plays a major role ...


Numerical Modeling Of Liquefaction In Layered And Silt Inter Layered Sands, Pelin Tohumcu Özener, I. Kutay Özaydın 2010 Yıldız Technical University, Turkey

Numerical Modeling Of Liquefaction In Layered And Silt Inter Layered Sands, Pelin Tohumcu Özener, I. Kutay Özaydın

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

In this paper, the pyhsical model tests which were carried out in the laboratory on uniform sand columns, silt inter layered sand columns and two layered sand columns deposited at various relative densities and subjected to different input accelerations are numerically modelled. The numerical analyses are performed by using Towhata-Iai liquefaction model in a finite element program called DIANA and the excess pore water pressures computed from the numerical analyses are compared with the experimental results. The numerical analyses have shown that the development of excess pore water pressures is highly influenced by the relative density of the sand and ...


Optimum Depth Of Seismic Drains For Mitigating Large Deformations In Liquefied Ground With Hydraulic Barrier, Mahmood Seid-Karbasi, Peter M. Byrne 2010 Golder Associates Ltd., Canada

Optimum Depth Of Seismic Drains For Mitigating Large Deformations In Liquefied Ground With Hydraulic Barrier, Mahmood Seid-Karbasi, Peter M. Byrne

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

Liquefaction of water saturated granular soils is one of the major risks that affect the safety and post-earthquake performance of infrastructure such as bridges, dams, buildings, and lifelines in various parts of the world. The seismically induced ground deformations are often the main concern when liquefaction occurs in significant zones of an earth structure or soil foundation. Recent studies including field data, centrifuge model testing and numerical investigations indicate that large lateral spreads and flow-slides in gentle sandy slopes have taken place when a low permeability silt/clay layer (hydraulic barrier) is present. One of the promising measures to alleviate ...


Parametric Investigation Of Lateral Spreading In Free-Face Ground Formations, Alexandros Valsamis, George Bouckovalas, Vasiliki Dimitriadi 2010 National Technical University of Athens, Greece

Parametric Investigation Of Lateral Spreading In Free-Face Ground Formations, Alexandros Valsamis, George Bouckovalas, Vasiliki Dimitriadi

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

Liquefaction-induced lateral spreading can cause extensive damage and even failure to foundations and earthworks resting inside or in the vicinity of the affected ground. The current practice for the evaluation of the ground surface displacement due to lateral spreading, is to rely upon a number of published empirical relations which are based on statistical analysis of field measurements. As an alternative, aimed to overcome a number of objective limitations related to the interpretation of field data, this article employs a numerical investigation to explore the main parameters affecting the anticipated maximum ground surface displacement and to quantify their effect in ...


Prediction Of Lateral Displacement Of Liquefaction Induced Ground Using Extreme Learning, Sarat Kumar Das 2010 National Institute of Technology Rourkela, India

Prediction Of Lateral Displacement Of Liquefaction Induced Ground Using Extreme Learning, Sarat Kumar Das

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

Though various mechanistic based models are there for prediction of lateral displacement of ground, the statistical/ empirical methods based on the insitu data is most widely used. The artificial neural network method has been extensively used an alternate statistical method in different complex geotechnical engineering problems. Due to inherent difficulty of generalization in artificial neural network method, support vector machine, which is based on statistical learning algorithm is also being used. This paper describes use of extreme learning machine for prediction of large lateral displacement of liquefaction induced ground during an earthquake. Extreme learning machine is an artificial intelligence techniques ...


Probabilistic Evaluation Of Field Liquefaction Potential Using Relative State Parameter Index (ΞR), Yaser Jafarian, Mohammad H. Baziar, Alireza Sadeghi, Rouzbeh Vakili 2010 Semnan University, Iran

Probabilistic Evaluation Of Field Liquefaction Potential Using Relative State Parameter Index (ΞR), Yaser Jafarian, Mohammad H. Baziar, Alireza Sadeghi, Rouzbeh Vakili

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

From the earliest studies of soil behavior under cyclic loading, it is found that the cyclic stress required for liquefaction onset is strongly affected by the relative density (Dr ) and initial effective overburden pressure of the soil. In this paper, relative state parameter index (ξR), which accounts for both relative density and effective stress, is used to evaluate the likelihood of liquefaction initiation in field condition. Two comprehensive databases of field case histories based on SPT and CPT are incorporated in the analyses. Logistic regression method is employed to derive a probabilistic expression that yields the probability of ...


Recent Advances In Liquefaction Of Fine Grained Soils, Shamsher Prakash, Vijay K. Puri 2010 Missouri University of Science and Technology

Recent Advances In Liquefaction Of Fine Grained Soils, Shamsher Prakash, Vijay K. Puri

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

Paper reviews present literature recommendations on liquefaction of soils with fines starting with the experimental evidence previously published by the authors. The liquefaction behavior of silts and silt clay mixers was investigated over a range of plasticity index values of interest by conducting cyclic triaxial tests on reconstituted samples and their behavior was compared with that of sand. It was found that saturated silts with plastic fines behave differently from sands both with respect to rate of development of pore water pressure and axial deformations with number of load cycles. The results also showed that liquefaction susceptibility of silts shows ...


Residual Shear Strengths Of Cohesionless Soils From Energy Approach, Raghvendra Singh, Debasis Roy 2010 Indian Institute of Technology, India

Residual Shear Strengths Of Cohesionless Soils From Energy Approach, Raghvendra Singh, Debasis Roy

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

The residual shear strength of the non plastic soils are generally estimated from the correlations between residual shear strength estimated from the laboratory tests or from the back analyses of post failure geometries of case histories distressed during static or seismic loading and penetration resistances. The post failure shear strength of large deformed structures like debris flow, mud flow and avalanches in which the post deformed soil mass gain large distance after the failure, depends on the strain rate behavior of shear (viscous) resistance, frictional resistance, inertial effect, three dimensional effect of geometry, flexibility of failed material and void redistribution ...


Seismic Analysis Of Saturated Sand Deposits With Silt Layers, Murat Tonaroglu, Kutay Ozaydın, S. Umit Dikmen 2010 Yildiz Technical University, Turkey

Seismic Analysis Of Saturated Sand Deposits With Silt Layers, Murat Tonaroglu, Kutay Ozaydın, S. Umit Dikmen

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

Liquefaction of saturated sands during earthquakes is known to be the cause of significant earthquake related damages, including loss of bearing capacity, lateral flow and spreading, slope failures. In recent earthquakes including the1999 Marmara Earthquake in Turkey, field observations have indicated that silt inclusions or silt layers in the sandy deposits can have significant effects on development of liquefaction. The objective of this work is to analytically study the behavior of saturated sand deposits with silt layers. For this purpose, a hypothetical soil profile in which silt layers exist has been selected. The selected profile was then modeled and analyzed ...


Some Seismological Characteristics Of Mw 6.5 Pishin-Ziarat October 29, 2008 Double Earthquake, Syed Kazim Mahdi 2010 WAPDA Directorate of Seismic Studies, Pakistan

Some Seismological Characteristics Of Mw 6.5 Pishin-Ziarat October 29, 2008 Double Earthquake, Syed Kazim Mahdi

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

On October 29, 2008 two shallow focused earthquakes of Mw 6.5 struck the Pishin-Ziarat districts of Baluchistan in Pakistan. Both seismic events took place between 12 hours of each other with Intensity X and have been termed as Double Earthquake. The Earthquakes are located approximately 50 km northeast of the region of most intense damage from the Pakistan earthquake of May 30, 1935 (Mw 7.8), which is estimated to have killed 35,000 people. Field observations in the earthquake affected areas were undertaken field observations along previously mapped seismically active Gogai, Bibai and Kawas Tangi faults and study ...


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