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2008

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General Report — Session 1: Analysis, Design, Testing And Performance Of Foundations, Rodrigo Salgado, Sanjeev Kumar, Dipanjan Basu, Gloria Maria Estrada Alvarez, Kenneth Gavin, Syed Faiz Ahmad Aug 2008

General Report — Session 1: Analysis, Design, Testing And Performance Of Foundations, Rodrigo Salgado, Sanjeev Kumar, Dipanjan Basu, Gloria Maria Estrada Alvarez, Kenneth Gavin, Syed Faiz Ahmad

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

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Assessment Of Some Old Earth Dams In Malaysia Through Observation And Computer Simulation, A. M. Thamer, J. M. M. N. Megat, B. B. K. Huat, A. A. Azlan Aug 2008

Assessment Of Some Old Earth Dams In Malaysia Through Observation And Computer Simulation, A. M. Thamer, J. M. M. N. Megat, B. B. K. Huat, A. A. Azlan

International Conference on Case Histories in Geotechnical Engineering

In this study, two earth dams located in Malaysia were studied. The Labong Dam is a non-homogenous earth dam, whilst the Bukit Merah Dam is a homogenous earth dam. The performances of both dams against seepage were studied through the analyses of both observed and simulated phreatic surfaces. Simulations of seepage rate and phreatic surfaces through the dam were conducted by using SEEP/W model. The study showed that the SEEP/W model was able to predict (simulate) both the seepage rates and phreatic surfaces of the homogeneous and non-homogeneous earth dams with a reasonable accuracy. The Absolute Error (AE) between the …

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Influence Of Kinematic Interaction Effects On Earthquake Structure Response: Analysis Of These Effects In The Colombia Earthquake Of November 15, 2004, Gloria Estrada Aug 2008

Influence Of Kinematic Interaction Effects On Earthquake Structure Response: Analysis Of These Effects In The Colombia Earthquake Of November 15, 2004, Gloria Estrada

International Conference on Case Histories in Geotechnical Engineering

Many authors have considered the kinematic interaction effects as favorable for seismic response of structures. However, this assumption is not always correct, because for some combinations of soil dynamic properties, foundation geometry and structural configuration, the kinematic interaction effects can lead to unfavorable performance of structures during earthquake. Therefore, the kinematic interaction effects increase or decrease the effective excitation that acts on the foundation base, in terms of their translation and rotation components. In this paper the role of kinematic interaction effects is analyzed for plate foundation embedded in different layered soil profiles, using recorded motions and several foundation geometries. …

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Predicting Hydraulic Fracturing In Hyttejuvet Dam, S. Mohsen Haeri, Danial Faghihi Aug 2008

Predicting Hydraulic Fracturing In Hyttejuvet Dam, S. Mohsen Haeri, Danial Faghihi

International Conference on Case Histories in Geotechnical Engineering

Hydraulic fracturing can occur in the clay core of earth and rockfill dams if the vertical effective stress in the core is reduced to the levels that are small enough to allow a tensile fracture to occur due to hydraulic pressure of the seeping water. This situation may arise if the total stress in the core is reduced by the “arching effect” where the core settles relative to the filter or rock-fill shell of the dam. Water pressure increase in the core which occurs on first impounding of water, may reduce effective stresses further, and if they reach low enough …

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Case Study On The Influence Of Transpiration On The Ground Behaviour, Behzad Fatahi, Buddhima Indraratna, Hadi Khabbaz Aug 2008

Case Study On The Influence Of Transpiration On The Ground Behaviour, Behzad Fatahi, Buddhima Indraratna, Hadi Khabbaz

International Conference on Case Histories in Geotechnical Engineering

Bioengineering including native vegetation is an ancient method of improving the stability of slopes. In modern railway engineering, this technique is re-captured for increasing the soil stiffness and shear strength of sub-grade beneath rail tracks. A mathematical model for the rate of root water uptake has been developed considering ground conditions, type of vegetation and climatic parameters. The three independent features in the root water uptake model considered in detail are soil suction, root distribution, and potential transpiration. In order to establish a rigorous analysis for estimating the actual transpiration or root water uptake, the above mentioned factors have been …

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Soil And Structure Vibrations From Construction And Industrial Sources, Mark R. Svinkin Aug 2008

Soil And Structure Vibrations From Construction And Industrial Sources, Mark R. Svinkin

International Conference on Case Histories in Geotechnical Engineering

Construction and industrial dynamic sources can produce environmental vibration problems for adjacent and remote structures. High vibrations and unacceptable dynamic settlements could disturb sensitive devices and people and even be the cause of structural damage. The dynamic sources, the geology at a site, and the condition of structures affect ground and structure vibrations. Each construction or industrial site is unique and requires consideration of specific approaches at the site for decreasing vibration effects of construction activities or industrial dynamic sources on surrounding structures. Specifications prepared for a site, calculation and prediction of expected vibrations, and monitoring and control of ground …

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Predicted Versus Observed Failure Surface: A Case Study, P. K. Basudhar, G. Bhattacharya Aug 2008

Predicted Versus Observed Failure Surface: A Case Study, P. K. Basudhar, G. Bhattacharya

International Conference on Case Histories in Geotechnical Engineering

The paper pertains to the studies undertaken to investigate the efficacy and correctness of a numerical scheme developed by the authors to predict the stability of slopes. As such, a well documented failed test embankment has been reanalyzed using the suggested method for predicting the critical slip surface and the associated factor of safety. A comparison of the predicted failure surface (critical slip surface) with the observed failure surface showed close agreement; the corresponding value of factor of safety was found to be close to unity. Thus, the case study demonstrated that with appropriate choice of the strength parameters the …

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Laboratory Studies Of Ice Formation Pathways From Ammonium Sulfate Particles, M. E. Wise, K. J. Baustian, M. A. Tolbert Aug 2008

Laboratory Studies Of Ice Formation Pathways From Ammonium Sulfate Particles, M. E. Wise, K. J. Baustian, M. A. Tolbert

CUP Faculty Research

Cirrus clouds are composed of ice particles and their formation pathways have been studied extensively in the laboratory. The ability of ammonium sulfate particles to act as nuclei for cirrus clouds has been of particular importance because of their ubiquitous presence in the upper troposphere. The results of past laboratory experiments of homogeneous ice nucleation from ammonium sulfate particles show a wide range of freezing conditions. In the present study, a flow tube apparatus equipped with Fourier transform infrared spectroscopy was used to resolve these discrepancies. It was found that when ammonium sulfate particles were preconditioned at 100% relative humidity …

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A Culture Of Technical Knowledge: Professionalizing Science And Engineering Education In Late-Nineteenth Century America, Paul Keith Nienkamp Aug 2008

A Culture Of Technical Knowledge: Professionalizing Science And Engineering Education In Late-Nineteenth Century America, Paul Keith Nienkamp

Electronic Reference Materials

This manuscript examines the intellectual, cultural, and practical approaches to science and engineering education as a part of the land-grant college movement in the Midwest between the 1850s and early 1900s. These land-grant institutions began and grew within unique frontier societies that simultaneously cherished self-reliance and diligently worked to make themselves part of the larger national experience. College administrators and professors encountered rapidly changing public expectations, regional needs, and employment requirements. They recognized a dire need for technically skilled men and women who could quickly adapt to changes in equipment and processes, and implement advances in scientific knowledge in American …

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Keeping Abreast Of Quantum News: Quantum Computing On The Web And In The Literature, Jill Cirasella Aug 2008

Keeping Abreast Of Quantum News: Quantum Computing On The Web And In The Literature, Jill Cirasella

Publications and Research

This appendix describes tools that can help you track developments in quantum computing.

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Performance Analysis Of Multicarrier Code Division Multiple Access (Mc-Cdma) Systems, Pravinkumar Patil Aug 2008

Performance Analysis Of Multicarrier Code Division Multiple Access (Mc-Cdma) Systems, Pravinkumar Patil

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Pravinkumar Patil on August 11, 2008.

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Moodys Letter To Lori Richards Regarding The Sec Examination, Michel Madelain Aug 2008

Moodys Letter To Lori Richards Regarding The Sec Examination, Michel Madelain

Documents

This letter is addressed to Lori Richards

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Board Of Directors Meeting Minutes (August 11, 2008), Dmacc Aug 2008

Board Of Directors Meeting Minutes (August 11, 2008), Dmacc

Board of Directors Meeting Minutes

This file contains the minutes from the Des Moines Area Community College Board meeting held on August 11, 2008.

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Geotechnical Characterization Of A Soft Clay Soil Subjected To A Preloading Embankment, Antonio Cavallaro, Salvatore Grasso, Valentina Lentini, Michele Maugeri Aug 2008

Geotechnical Characterization Of A Soft Clay Soil Subjected To A Preloading Embankment, Antonio Cavallaro, Salvatore Grasso, Valentina Lentini, Michele Maugeri

International Conference on Case Histories in Geotechnical Engineering

The paper presents the geotechnical characterization of a clay soil subjected to a preloading embankment for the construction of an industrial electronics building in the industrial area (STM M6) of Catania (Sicily, Italy). To determine the geological profile and the geotechnical characteristics of the soil, the site was well investigated by means of in situ and laboratory tests. The following in situ geotechnical tests were carried out: Borings, SPT, CPT, PLT and dynamic in situ tests have been performed. Among them Down-Hole (D-H), Cross-Hole (C-H), SASW and recently Seismic Dilatometer Marchetti Tests (SDMT) have been carried out, with the aim …

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Settlement Analysis Of Chek Lap Kok Trial Embankments With Probabilistic Extensions, Bak Kong Low Aug 2008

Settlement Analysis Of Chek Lap Kok Trial Embankments With Probabilistic Extensions, Bak Kong Low

International Conference on Case Histories in Geotechnical Engineering

Several test reclamation fills were constructed in Hong Kong in the 1980s on marine clay installed with prefabricated vertical drains prior to the construction of the Chek Lap Kok airport. Instrumentation data including settlement with time were available in the literature. The first part of this paper presents the author’s deterministic settlement analysis for comparisons with the instrumented settlement-versus-time records of the marine clay. The second part of the paper illustrates, in the context of the Chek Lap Kok test fills, a new and efficient spreadsheet-based first-order reliability algorithm. Comparisons are made with results from Monte Carlo simulations. The proposed …

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Cratering And Blowing Soil By Rocket Engines During Lunar Landings, Philip T. Metzger, John E. Lane, Christopher D. Immer, Sandra Clements Aug 2008

Cratering And Blowing Soil By Rocket Engines During Lunar Landings, Philip T. Metzger, John E. Lane, Christopher D. Immer, Sandra Clements

International Conference on Case Histories in Geotechnical Engineering

This paper is a summary compilation of work accomplished over the past decade at NASA’s Kennedy Space Center to understand the interactions between rocket exhaust gases and the soil of the Moon or Mars. This research is applied to a case study of the Apollo 12 landing, in which the blowing soil peppered the nearby Surveyor III spacecraft producing measurable surface damage, and to the Apollo 15 landing, in which the Lunar Module tilted backwards after landing in a crater that was obscured from sight by the blowing dust. The modeling coupled with empirical observations is generally adequate to predict …

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Soil-Structure Interaction And Uls Design Of Complex Deep Foundations, Rolf Katzenbach, Gregor Bachmann, Christian Gutberlet Aug 2008

Soil-Structure Interaction And Uls Design Of Complex Deep Foundations, Rolf Katzenbach, Gregor Bachmann, Christian Gutberlet

International Conference on Case Histories in Geotechnical Engineering

In conventional design of deep foundations, some important positive effects evolving from the interaction of the bearing elements and the subsoil (Soil-Structure Interaction) are not utilised. These positive effects especially arise when using Combined Pile-Raft Foundations (CPRFs). The application of numerical methods during the design process of such foundations, which is explicitly allowed in Eurocode 7, is capable of regarding these effects. This paper deals with an approach using numerical methods within the ULS design for complex foundations and discusses case histories where CPRFs are used as a foundation for high-rise buildings in Frankfurt am Main. The paper will be …

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Application Of Simplified Models To Qualitative Geotechnical Analysis, V. A. Barvashov, P. V. Kharlamov, A. I. Naidenov, S. A. Rytov Aug 2008

Application Of Simplified Models To Qualitative Geotechnical Analysis, V. A. Barvashov, P. V. Kharlamov, A. I. Naidenov, S. A. Rytov

International Conference on Case Histories in Geotechnical Engineering

The paper describes an approach for qualifying soil-structure systems behavior, using simple numeric models – “geotoys”, reflecting the main features of the systems behavior and enabling numeric simulation of various case histories. Three case histories of major karstic sinkholes are analyzed to show that man-made structures above a karstic cavity prevent formation sinkhole. When plastic zones reach the structure periphery, the soil-structure system becomes unstable. Prior settlements could be negligible to serve as precursors. Another soil-footing-superstructure (SFSS) model is a 2D geotoy - an exact mathematical solution, used for multiple simulations (about 10,000) of SFSS sensitivity i.e., response to input …

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Overnights Encourage Girls’ Interest In Science-Related Careers, Kimberly Christman, Sara Hankemeier, Jennifer Hunter, Johnna Jennings Aug 2008

Overnights Encourage Girls’ Interest In Science-Related Careers, Kimberly Christman, Sara Hankemeier, Jennifer Hunter, Johnna Jennings

Journal of Youth Development

With sell-out crowds and phenomenal research results, Science Siesta and Advanced Science Siesta are programs designed to change the traditional perceptions that girls have about science and science-related careers. Through hands-on science activities (in and out of the lab), and through working with local female scientists, girls who range from fourth to eighth grade are provided valuable opportunities to combat the stereotype that “girls can’t do science.” This article addresses the need to engage girls in science and explains “how-to” meet that need through the Science Siesta programs.

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A Radical Conjugate Addition Approach To The Total Synthesis Of Celogentin C, Steven G. Capps Aug 2008

A Radical Conjugate Addition Approach To The Total Synthesis Of Celogentin C, Steven G. Capps

Theses and Dissertations

The synthesis of five chiral DBFOX (dibenzofuran-oxazoline) ligands with either aryl or benzyl substituents will be presented. The requisite amino alcohols were obtained with high enantioselectivity either commercially (DBFOX/Bn), via Sharpless asymmetric aminohydroxylation (DBFOX/Nap, DBFOX/t-BuPh, DBFOX/Pip), or via phase-transfer catalyzed asymmetric alkylation (DBFOX/MeNap). These ligands, complexed with Mg(NTf2)2, were used as Lewis acid promoters of enantioselective radical conjugate additions to α/β-unsaturated nitro-amides/esters. A summary of these results is presented and discussed. These findings led us to believe that our initial binding model between metal, ligand, and substrate was flawed. Thus, we figured that if we started with a functionality known …

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Evolution Of Soil Desaturation By Air-Injection Technique And Its Evaluation Via Multiphase Flow Simulation, Hide Yasuhara, Takamasa Morito, Yoshinori Kochi, Mitsu Okamura Aug 2008

Evolution Of Soil Desaturation By Air-Injection Technique And Its Evaluation Via Multiphase Flow Simulation, Hide Yasuhara, Takamasa Morito, Yoshinori Kochi, Mitsu Okamura

International Conference on Case Histories in Geotechnical Engineering

In this study the simplified model tests that simulate air injection into saturated soils using air-injection probes, are conducted using the two different sizes of soil containers. The experiments using the small container are aimed to examine the rates and magnitudes of the soil desaturation driven by air injection, whilst those with the large container are performed to obtain not only the rates and magnitudes but also the distributions of the desaturated zones within the soil, and to examine influences on the desaturation process exerted by anisotropy of the soil in terms of flow transport. Obtained results indicate that the …

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Improvement Of Thermal Resistivity Of Desert Sand For Use In High Voltage Cable Beddings And Foundation In Arid Zones, Muawia A. Dafalla Aug 2008

Improvement Of Thermal Resistivity Of Desert Sand For Use In High Voltage Cable Beddings And Foundation In Arid Zones, Muawia A. Dafalla

International Conference on Case Histories in Geotechnical Engineering

The soil thermal resistivity is of a great importance for the design of high voltage cables. Underground cables generate heat as a result of power losses when transmitting current. This heat must be dissipated in a form that will not affect the performance of the cables. The presence of moisture normally helps to reduce the thermal resistivity and keeps it within the design range. In arid areas the moisture content is decreased to very low values in dry seasons. This is found to bring the thermal resistively beyond the design ranges. Major cable failures took place during summer times in …

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Need For Prior Geotechnical Engineering Studies For Foundation Design: Cases Of Collapsed Buildings In Port Harcourt And Environs, Nigeria, So-Ngo Clifford Teme, O. D. Ngerebara, Essien Ubong Aug 2008

Need For Prior Geotechnical Engineering Studies For Foundation Design: Cases Of Collapsed Buildings In Port Harcourt And Environs, Nigeria, So-Ngo Clifford Teme, O. D. Ngerebara, Essien Ubong

International Conference on Case Histories in Geotechnical Engineering

Cases of collapsed buildings have been on the increase in the city of Port Harcourt and environs in Rivers State, in particular and other major cities in Nigeria in recent times. A critical evaluation of the modes of failures indicates that absence of and / or inadequate subsurface geotechnical investigations have been responsible for these building foundation failures. Case histories of four major building foundation failures within the municipality of Port Harcourt and environs in the southern Niger Delta sub-region of Nigeria in recent times are presented and discussed in this paper. The first case history involves a five-storey building …

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Case Histories In Geotechnical Engineering: Enhancing The Practice In An Interactive Learning Environment, Waddah Akili Aug 2008

Case Histories In Geotechnical Engineering: Enhancing The Practice In An Interactive Learning Environment, Waddah Akili

International Conference on Case Histories in Geotechnical Engineering

This paper focuses on the utilization of case histories in supplementing classroom education, and describes the steps taken in planning, developing, and executing a case study/case history course in geotechnical/foundation engineering at an international university. The paper sheds light on: how a “workable” format for the course was arrived at; the organization of the course; and the results of evaluating the effectiveness of this approach versus traditional lecturing. Problems and challenges that could arise when offering the course for the first time are also addressed. Embedded in this experience and its related protocols are: the emphases on engineering design, the …

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From Case Histories To Conceptual Models, Liaqat Ali, Sarfraz Ali Aug 2008

From Case Histories To Conceptual Models, Liaqat Ali, Sarfraz Ali

International Conference on Case Histories in Geotechnical Engineering

Geotechnical engineering deals with complicated and highly variable set of engineering principles. A typical geotechnical engineering project comprises site characterization, foundation / soil treatment design, execution, monitoring and quality control systems. Unlike some other civil engineering designs, highly variable soil conditions make a geotechnical designs an iterative and repetitive process which in-turn make these designs cost and time intensive. Economy and optimization of geotechnical designs are dependent on comprehensive site characterization and evaluation of multiple alternatives. Availability of up-to-date data sets of geotechnical case histories covering entire spectrum; from techniques / technologies to results can help reduce both cost and …

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Monitoring Seismic And Geophysical Paprameters With The Help Of College Instruments And Staff, Arun Bapat Aug 2008

Monitoring Seismic And Geophysical Paprameters With The Help Of College Instruments And Staff, Arun Bapat

International Conference on Case Histories in Geotechnical Engineering

A number of geophysical and seismically significantly related parameters are routinely measured in college laboratories. These are Magnetic field, Gravity field, Radioactivity, sub-surface temperature. After one major earthquake in India (M = 6.5, Latur earthquake of 29 September 1993) some colleges were used to measure these parameters. These parameters show premonitory changes prior to the occurrence of main shock. As the experiment was undertaken during post-seismic period the magnitudes of the seismic events were in the range of 4.5 to 5.0. The advantage of such method is that these are extended over an extensive area.

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Streamlining Case Studies For Education, Peter Scharle Aug 2008

Streamlining Case Studies For Education, Peter Scharle

International Conference on Case Histories in Geotechnical Engineering

Recent results of cognitive psychology seem to confirm that post secondary education in civil engineering can be conceived as introduction to the world of models, and to the model selection and application skills. From this perspective, case study analysis turns to be one of the most efficient approaches used worldwide by educators teaching geotechnics. BSc and MSc levels of knowledge and competency are easy to distinguish and characterize plausibly in this conceptual framework. Significance of the MSc level thinking in geotechnics proves to be a consequence. Plenty of case studies, in principle, can be selected to meet the educational purposes, …

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Other Special (Osp) Lectures, Multiple Authors Aug 2008

Other Special (Osp) Lectures, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

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Use Of Case Histories To Enhance Practical Geotechnical Engineering, K. S. Babu Narayan, B. M. Sunil Aug 2008

Use Of Case Histories To Enhance Practical Geotechnical Engineering, K. S. Babu Narayan, B. M. Sunil

International Conference on Case Histories in Geotechnical Engineering

Mathematical models are constructed to describe the behavior of engineering systems in quantitative terms. During conceptualization stage of modelling several valid assumptions have to be made so as to make the model predict the behavior of the system as accurately as possible. Refinement of mathematical models need feed back from practice. Many practical cases are of interest in updating and enhancing quantitative judgment of geo-technical systems behavior. This paper envisages to present a few interesting cases where the situation forced true synthesis of theory and practice for innovation and advancement of practical geo-technical engineering.

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Risk Analysis In Geotechnical And Earthquake Engineering: State-Of-The-Art And Practice For Embankment Dams, D. N. D. Hartford Aug 2008

Risk Analysis In Geotechnical And Earthquake Engineering: State-Of-The-Art And Practice For Embankment Dams, D. N. D. Hartford

International Conference on Case Histories in Geotechnical Engineering

The nature of risk analysis as applied to earthfill dams for the purpose of safety assessment is examined with particular reference to the matter of demonstrating the scientific validity of risk constructs used to inform important dam safety decisions. The qualities and attributes of what would be considered to be transparent, credible and defensible risk analyses for dam safety decision-making are outlined. A conceptual approach to addressing the problem of quantifying internal erosion risk that combines critical state soil mechanics theory and dynamic event tree analysis is proposed. Finally, an experiment aimed at assessing contemporary capability to detect the “changes …

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