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Performances Of Rockfill Dams During Recent Large Earthquakes, Kenji Ishihara 2010 Chuo University, Japan

Performances Of Rockfill Dams During Recent Large Earthquakes, Kenji Ishihara

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

There has been increasingly high intensity of acceleration ever recorded during earthquakes in recent times. In consistence with this trend several characteristics have been unearthed regarding performances of rockfill dams. With due considerations to these, damage features of high rockfill dams during recent earthqukes in Japan and China are briefly introduced herein, together with those previously reported. As an indicator of overall distress to the dams, the crest settlement was taken up and it was shown that the settlement tends to increase up to about 1.5% of the height of the dam with increasing acceleration during earthquakes.


Sand Plasticity Model For Nonlinear Seismic Deformation Analyses, Ross W. Boulanger 2010 University of California, Davis, CA

Sand Plasticity Model For Nonlinear Seismic Deformation Analyses, Ross W. Boulanger

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

A sand plasticity model for nonlinear seismic deformation analyses is presented. The model follows the basic framework of the stressratio controlled, critical state compatible, bounding surface plasticity model for sand presented by Dafalias and Manzari (2004). Modifications to the model were implemented to improve its ability to approximate the stress-strain responses important to geotechnical earthquake engineering applications; in essence, the model was calibrated at the equation level to provide for better approximation of the trends observed across a common set of experimentally- and case history-based design correlations. An overview of the model formulation and example simulations of element loading tests ...


Criterions, Prediction And Prevention Of Loess Liquefaction, Lanmin Wang, Zhongxia Yuan, Haimei Sun, Jin Deng 2010 Lanzhou Institute of Seismology, China Earthquake Administration, China

Criterions, Prediction And Prevention Of Loess Liquefaction, Lanmin Wang, Zhongxia Yuan, Haimei Sun, Jin Deng

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

Although loess liquefaction is not very common during earthquakes in Northwest of China, it is disastrous if it happens. Both study and valid evidence from Haiyuan 8.5 Earthquake in 1920 and Tajikistan 5.9 Earthquake in 1989 have proved that loess liquefaction could be very disastrous under certain conditions. In this paper, the criterions of loess liquefaction are discussed to show that unlike typical liquefaction of sand, loess which falls into the category of both silt clay and clayey silt has unique characteristics during liquefaction test. To predict liquefaction of loess, a simple method based on laboratory test and ...


Effects Of Sample Disturbance And Consolidation Procedures On Cyclic Strengths Of Intermediate Soils, Karina R. Dahl, Ross W. Boulanger, Jason T. DeJong, Michael W. Driller 2010 University of California, Davis, CA

Effects Of Sample Disturbance And Consolidation Procedures On Cyclic Strengths Of Intermediate Soils, Karina R. Dahl, Ross W. Boulanger, Jason T. Dejong, Michael W. Driller

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

Sampling and testing of soils to measure engineering properties, such as monotonic and cyclic undrained shear strengths, requires an understanding of the potential effects of sampling disturbance and the selection of appropriate laboratory testing procedures. For clays, past research has provided insights on how sampling methods and laboratory testing procedures can be used in practice to assess and minimize sample disturbance effects. For sands, past research has shown that conventional tube sampling techniques cause excessive disturbance to the soil fabric, such that subsequent measurement of monotonic or cyclic strengths can be greatly in error and misleading. For intermediate soils, the ...


Ground Improvement For Increasing Lateral Pile Group Resistance, Kyle M. Rollins, Matthew E. Adsero, Mark A. Herbst, Nathan Lemme 2010 Brigham Young University, Provo, UT

Ground Improvement For Increasing Lateral Pile Group Resistance, Kyle M. Rollins, Matthew E. Adsero, Mark A. Herbst, Nathan Lemme

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

Lateral load tests were performed on a full-scale pile cap in untreated clay along with pile groups involving (a) excavation and replacement with sand backfill, (b) a soilcrete wall along the side of the pile group, and (c) a jet grouted zone below the pile cap. The average compressive strength of the soft, plastic clay increased from an average of 50 kPa to an average of about 1000 kPa with soil mixing (10% cement) and to 3000 kPa with jet grouting (20% cement). Excavation and replacement only increased resistance by about 20%; however, the soil mixed wall increased resistance by ...


Liquefaction-Induced Movements Of Buildings With Shallow Foundations, Jonathan D. Bray, Shideh Dashti 2010 University of California Berkeley, Berkeley, CA

Liquefaction-Induced Movements Of Buildings With Shallow Foundations, Jonathan D. Bray, Shideh Dashti

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

Seismically induced settlement of buildings with shallow foundations on liquefiable soils has resulted in significant damage in recent earthquakes. In Adapazari, Turkey multi-story buildings punched into, tilted excessively, and slid laterally on softened ground. The state-of-the-practice still largely involves estimating building settlement using empirical procedures developed to calculate postliquefaction consolidation settlement in the free-field. This approach cannot possibly capture shear-induced and localized volumetricinduced deformations in the soil underneath shallow mat foundations. Geotechnical centrifuge experiments were performed recently to identify the dominant mechanisms involved in liquefaction-induced building settlement. The centrifuge tests revealed that considerable building settlement occurs during earthquake strong shaking ...


Liquefaction Induced Settlement Of Structures, Gopal S. P. Madabhushi, Stuart K. Haigh 2010 University of Cambridge, U. K.

Liquefaction Induced Settlement Of Structures, Gopal S. P. Madabhushi, Stuart K. Haigh

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

Soil liquefaction following earthquakes leads to excessive damage to a wide variety of structures. Settlement and rotation of structures following liquefaction have been witnessed in many of the recent earthquakes. Investigation of the mechanisms of failure of structure when the foundation soil suffers either partial or full liquefaction is therefore very important. Dynamic centrifuge tests were conducted at Cambridge and elsewhere on different boundary value problems in which liquefaction of soil models was investigated. Excess pore pressure data and the settlement data for the particular structure that is being investigated are recorded during the centrifuge tests. In this paper the ...


Liquefaction, Screening, And Remediation Of Silty Soils, S. Thevanayagam 2010 University at Buffalo, SUNY Buffalo, NY

Liquefaction, Screening, And Remediation Of Silty Soils, S. Thevanayagam

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

Assessing liquefaction potential, in situ screening, and remediation of non-plastic silty soils are difficult problems. Presence of silt particles among the sand grains in silty soils affects the soil response in each of the above cases in different ways. First part of this paper addresses the effects of silt content on liquefaction resistance, hydraulic conductivity, and coefficient of consolidation of silty soils compared to clean sand. Secondly it addresses the effects of silt content and consolidation characteristics on cone resistance of silty soils and sand. A relationship between normalized cone resistance, liquefaction resistance, and consolidation characteristics is presented. The third ...


Principles And Practices Of Seismic Microzonation: Case Studies In India, T. G. Sitharam, P. Anbazhagan, K. S. Vipin 2010 Indian Institute of Science, India

Principles And Practices Of Seismic Microzonation: Case Studies In India, T. G. Sitharam, P. Anbazhagan, K. S. Vipin

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

This paper presents an overview of the principles and practices of seismic microzonation with some case studies in India. India has experienced major damages and loss of life due to earthquakes. Macrozonation map in Indian seismic code IS-1893 is frequently revised soon after a major earthquake in the country. New revision which was published in 2002 after Bhuj earthquake in 2001 contains four macro zones. These zones are based on geology and limited seismology input without considering geotechnical aspects such as site effects and liquefaction. In order to understand the earthquake vulnerability of major urban centers and prepare new zonation ...


Recent Advances In Non-Linear Site Response Analysis, Youssef M. A. Hashash, Camilo Phillips, David R. Groholski 2010 University of Illinois at Urbana-Champaign, Urbana, Illinois-USA 61801

Recent Advances In Non-Linear Site Response Analysis, Youssef M. A. Hashash, Camilo Phillips, David R. Groholski

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

Studies of earthquakes over the last 50 years and the examination of dynamic soil behavior reveal that soil behavior is highly nonlinear and hysteretic even at small strains. Non-linear behavior of soils during a seismic event has a predominant role in current site response analysis. The pioneering work of H. B. Seed and I. M. Idriss during the late 1960’s introduced modern site response analysis techniques. Since then significant efforts have been made to more accurately represent the non-linear behavior of soils during earthquake loading. This paper reviews recent advances in the field of non-linear site response analysis with ...


Recent Advances In Seismic Design Of Geosynthetically-Lined Waste Containment Facilities, Neven Matasovic 2010 Geosyntec Consultants, Huntington Beach, CA

Recent Advances In Seismic Design Of Geosynthetically-Lined Waste Containment Facilities, Neven Matasovic

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

Geosynthetic materials are essential elements of almost all modern landfill barrier systems. Materials such as geomembranes and geosynthetic clay liners are widely used as resistive barrier elements while geotextiles, drainage nets, and geocomposites are widely employed in modern composite barrier systems for both landfill liners and covers. The ability of these geosynthetic elements to maintain their integrity when subject to deformations due to waste settlement and seismic loading is a major uncertainty with respect to the performance of modern landfills. Over past years, advances have been made in understanding of material behavior under cyclic loading, modeling of modern landfill response ...


Recent Advances In Terrestrial Lidar Applications In Geotechnical Earthquake Engineering, Roberto Kayer, Jonathan P. Stewart, Brian D. Collins 2010 U.S. Geological Survey, Menlo Park, CA

Recent Advances In Terrestrial Lidar Applications In Geotechnical Earthquake Engineering, Roberto Kayer, Jonathan P. Stewart, Brian D. Collins

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

During the past five years, geotechnical earthquake engineering and ground deformation research has benefited from the advent of terrestrial LIDAR technology, a revolutionary tool for characterizing fine-scale changes in topography. For ground deformation research, LIDAR is particularly useful for characterizing the dimensions of failures and for monitoring subtle deformations through time. Tripod mounted LIDAR systems have accuracies of approximately 0.4-2.0 cm, and can illuminate targets up to one kilometer away from the sensor. During several minutes of LIDAR scanning, millions of survey position points are collected and processed into an ultra-high resolution terrain model. During earthquake reconnaissance efforts ...


Zero-Gravity Triaxial Shear Tests On Mechanical Properties Of Liquefied Sand And Performance Assessment Of Mitigations Against Large Ground Deformation, Ikuo Towhata, Trinh Thi Lan Anh, Suguru Yamada, Ramin Motamed, Yoshikazu Kobayashi 2010 University of Tokyo, Japan

Zero-Gravity Triaxial Shear Tests On Mechanical Properties Of Liquefied Sand And Performance Assessment Of Mitigations Against Large Ground Deformation, Ikuo Towhata, Trinh Thi Lan Anh, Suguru Yamada, Ramin Motamed, Yoshikazu Kobayashi

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

This paper concerns prediction of liquefaction-induced large deformation of geotechnical structures that will play major roles in practice of seismic performance design. To do this prediction, it is essential to establish a mechanical model for liquefied sand in which effective stress is null or extremely low. Although past model tests suggested that liquefied sand behaves similar to viscous liquid, there is an opinion against it that pore water pressure distribution in embedded structures produces an apparent rate-dependent behavior. This opinion was examined precisely and quantitatively by analyzing a full-scale model test to find that the pore pressure theory cannot account ...


Geotechnical Aspects Of Recent Japan Earthquakes, Susumu Yasuda, Tomohiro Tanaka 2010 Tokyo Denki University, Japan

Geotechnical Aspects Of Recent Japan Earthquakes, Susumu Yasuda, Tomohiro Tanaka

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

Recently middle class earthquakes have occurred and caused various geotechnical damages every year in Japan. Among them geotechnical damages during five earthquakes from 2004 to 2008 are introduced. The 2004 Niigataken-chuetsu earthquake caused failure of expressway embankments and uplift of sewage manholes. Liquefaction-induced damage to quay walls and tanks occurred in artificially reclaimed lands during the 2005 Fukuokaken-seiho-oki earthquake. Liquefiable area had been predicted about 17 years before the earthquake. Liquefied zones were fairly coincided with the predicted liquefiable zones. Very severe slide of highway embankments occurred at 11 sites during the 2007 Notohanto earthquake. During the 2007 Niigataken-chuetsu-oki earthquake ...


Geotechnical Aspects Of Recent Pakistan Earthquakes, Sarfaraz Ali, Liaqat Ali, Muhammad Ammar 2010 NUST Institute of Civil Engineering, Pakistan

Geotechnical Aspects Of Recent Pakistan Earthquakes, Sarfaraz Ali, Liaqat Ali, Muhammad Ammar

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

Geologically, Kashmir and northwestern areas of Pakistan are located in most active seismic zones of sub-continent. In Kashmir area, earthquakes had been triggered by a continuous subduction phenomenon of Indian plate under Eurasian plate; a collision zone that created Himalaya Mountain range and still giving it a rise of 1 cm each year. The Quetta earthquake occurred on part of the left-lateral Chaman Fault System and was measured 8.1 on Richter scale with focal depth of 17 km. The earthquake completely devastated the city of Quetta, leaving 35000-60000 dead and injuring thousands of people in affected areas. The Kashmir ...


Reconnaissance Report Of The May 28, 2009 Honduras Earthquake, M 7.3, Ronaldo Luna 2010 Missouri University of Science and Technology

Reconnaissance Report Of The May 28, 2009 Honduras Earthquake, M 7.3, Ronaldo Luna

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

A team sponsored by the Earthquake Engineering Research Institute (EERI) and the Geoengineering Extreme Event Reconnaissance (GEER) Association carried out a field investigation in conjunction with Honduran colleagues from June 18-23 to document effects of the May 28 earthquake. The EERI-GEER team was invited by Mr. Marco Sandoval, Executive Director of the Comisión Ejecutiva Valle de Sula (CEVS). Mr. Sandoval sent a team of engineers to accompany the EERI-GEER team. The team included experts in structural, geotechnical engineering, as well as in disaster response and recovery. The investigators were supported by EERI: Abdeldjelil Belarbi and GEER: Ronaldo Luna and Kermit ...


Strong Ground Motion In The Epicentral Region Of The MW 6.3, Apr 6 2009, L’Aquila Earthquake, Italy, Roberto Paolucci, Chiara Smerzini 2010 Politecnico di Milano, Italy

Strong Ground Motion In The Epicentral Region Of The MW 6.3, Apr 6 2009, L’Aquila Earthquake, Italy, Roberto Paolucci, Chiara Smerzini

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

In the night of Apr 6 2009, a Mw 6.3 earthquake struck the Abruzzi region and the whole Central Italy, causing about 300 deaths and vast destructions in the town of L'Aquila, one of the largest urban centres in Central Italy, and its surroundings. As most destructive earthquakes in the Italian Central and Southern Apennines mountain chain, this was caused by a normal fault rupture, the epicenter of which was estimated at less than 5 km from the center of L'Aquila. Several 3-components digital strong motion instruments were installed around L'Aquila at few km distance ...


The Non-Regularity Of Earthquake Recurrence In California: Lessons From Long Paleoseismic Records From The San Andreas And San Jacinto Faults In Southern California, And The North Anatolian Fault In Turkey, Thomas Rockwell 2010 San Diego State University, San Diego, CA/ Earth Consultants International, Santa Ana, CA

The Non-Regularity Of Earthquake Recurrence In California: Lessons From Long Paleoseismic Records From The San Andreas And San Jacinto Faults In Southern California, And The North Anatolian Fault In Turkey, Thomas Rockwell

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

A long paleoseismic record at Hog Lake on the central San Jacinto fault in southern California documents evidence for 18 surface ruptures in the past 3.8-4 ka. This yields a long-term recurrence interval of about 210 years, consistent with its slip rate of ~15 mm/yr and field observations of 3-3.5 m of displacement per event. However, during the past 3800 years, the fault has switched from a quasiperiodic mode of earthquake production, during which the recurrence interval is similar to the long-term average, to clustered behavior with the inter-event periods as short as a few decades (five ...


A Structural Engineer’S Approach To Efficient Sfsi: Towards Performance Based Design, M. Hesham El Naggar 2010 The University of Western Ontario, Canada

A Structural Engineer’S Approach To Efficient Sfsi: Towards Performance Based Design, M. Hesham El Naggar

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

Performance-based design (PBD) involves designing structures to achieve specified performance targets under specified levels of seismic hazard. This involves analyzing the entire soil-structure system and requires structural and geotechnical expertise. This paper is focused on soil-foundation-structure interaction (SFSI) in relation to PBD. A Beam-on-Nonlinear-Winkler- Foundation (BNWF) model is developed to incorporate important SFSI aspects into structural analysis software. The model accounts for: nonlinearity due to soil yield and/or footing uplift; cyclic degradation of stiffness and strength due to variable-amplitude loading; distribution of soil resistance underneath the footing for different loading conditions; reduction in radiation damping with increased nonlinearity; and ...


An Innovative Procedure For The Rapid Mapping Of Urban Earthquake Vulnerability, Filippo Ciuffi 2010 intraVidére Research Institute, Italy

An Innovative Procedure For The Rapid Mapping Of Urban Earthquake Vulnerability, Filippo Ciuffi

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

The present paper summarizes the original approach, the different stages, the innovative algorithms and the most interesting results of a new, “simplified procedure” for mapping Earthquake Vulnerability in urban areas. The devised procedure is based on the processing data generated by “Remote Sensing Techniques”, for the design and the construction of two different square matrixes: Building Vulnerability Matrix and Soil Vulnerability Matrix. Combination of mathematical classification procedures and matrix analysis techniques have been designed and implemented, for creating the “basic models” of the mentioned matrixes, together with the related algorithms, “ad hoc” devised. The classes and the groups generated within ...


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