Engineering Commons^™

General Report Session No. 14: Geotechnical Aspects Of Recent Earthquakes, Ahmed-W. Elgamal, G. L. Hempen

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Geotechnical Aspects Of The Petrolia Earthquake, Robert K. Green, Thomas L. Sawyer

International Conference on Case Histories in Geotechnical Engineering

The Petrolia, California earthquake (M_S 6.9, M_L 6.4) occurred on April 25, 1992 and was followed by numerous aftershocks including two earthquakes over magnitude 6 that occurred on April 26, 1992. The earthquakes caused structural damage in Ferndale, Petrolia, Honeydew, Rio Dell, Fortuna, and Scotia. The earthquake also produced ground failures of liquefaction, lateral spreads, and landslides in the epicentral region. Liquefaction did not appear to be widespread, and occurred in locations where it would most likely be expected to occur (low lying areas with very recent alluvial deposits and high ground water). Scattered landslides were triggered by …

Ground Movements In Mexico City During Recent Earthquakes, E. Ovando, M. P. Romo, L. Díaz

International Conference on Case Histories in Geotechnical Engineering

Acceleration records were obtained with a rather dense accelerographic array during three recent earthquakes in Mexico City. Following a purely observational approach, useful information about the nature and characteristics of seismic motions was derived from the analysis of these records. Broad regional studies indicate that the distribution of seismic motions in the city may be affected by directivity effects. From local site studies it is concluded that seismic movements at the base of the compressible clay deposits are fairly uniform and accelerograms recorded in vertical arrays suggest that soil strata in Mexico City respond to seismic movements according to established …

Liquefaction During 1988 Earthquakes And A Case Study, M. K. Gupta

International Conference on Case Histories in Geotechnical Engineering

Several parts of north eastern India, Bangladesh and Burma were rocked by an earthquake on August 6, 1988. The author carried out earthquake damage survey due to liquefaction in Assam region. Wide spread liquefaction in the area was observed. Guide bunds and approach roads of a road bridge near Tezpur performed excellently against liquefaction during the earthquake for which they were designed. Another earthquake of magnitude 6.6 visited Nepal Bihar border region which shook northern Bihar and Nepal region and was felt as far as Jaipur in the west and Shillong in the east. Large scale liquefaction has also been …

Liquefaction During The October 12, 1992, Egyptian Dahshure Earthquake, Ahmed-W. Elgamal, Mohamed Amer, Korhan Adalier

International Conference on Case Histories in Geotechnical Engineering

On October 12, 1992 a moderate earthquake M_B = 5.9 (M_S = 5.2) occurred about 18 km southwest of the center of Cairo and resulted in significant damage to numerous poorly constructed structures. Soil liquefaction associated with the occurrence of large sand-boils was observed close to the epicenter. As a consequence, a main road suffered a maximum settlement of about 1.75 m. In this study, the earthquake characteristics, soil profiles and resulting liquefaction are discussed. The observed liquefaction mechanisms provide valuable information on the seismic response of Nile deposited alluvial soils. Such soils constitute much of the inhabited …

Nonlinear Dynamic Effective-Stress Analysis Of Two Case Histories, S. Inel, W. H. Roth, C. De Rubertis

International Conference on Case Histories in Geotechnical Engineering

Two case histories were analyzed to determine the validity of using nonlinear numerical analysis methods together with simple and familiar descriptions of soil behavior to predict shaking-induced excess pore pressures and permanent deformations within soil. The first case focuses on the prediction of liquefaction during centrifuge testing of a silt layer underlain by sand. The second case involves the prediction of behavior of the Upper San Fernando Dam during the 1971 San Fernando earthquake. Results of both analyses show that consistent and reasonably accurate estimates may be made of the behavior of soil during seismic loading. The relative simplicity of …

Response Analyses Of Recorded Earthquake Motions, S. J. Serhan

International Conference on Case Histories in Geotechnical Engineering

Response analyses of three recorded earthquakes at a nuclear power plant have been conducted. The objective of the response analyses is to obtain frequency composition, assess damage potential, and simulate and explain the recorded soil and structural seismic motions. Two- and three-dimensional models for the soil/structure system have been developed by using the finite-element substructuring method. Results of the analyses show clear evidence of soil/structure interaction in terms of significant soil softening, strong rocking mode participation and unusual recorded high-frequency response inside the buildings.

Soil Liquefaction During The 1991 Telire-Limón, Costa Rica, Earthquake, Susumu Yasuda, Hiroyuki Watanabe, Nozomu Yoshida, Sergio Mora

International Conference on Case Histories in Geotechnical Engineering

The 1991 Telire-Limón Earthquake of magnitude 7.5 caused significant damage in Costa Rica and Panama. Soil liquefaction occurred widely in the low lying area in eastern Costa Rica, which caused severe damage to the embankment, bridges, and houses, etc. The liquefied sites are classified into three categories: 1) inland areas along rivers, 2) sand bars along beach, and 3) coastal areas along rivers. In inland area, road embankment of Route 32 was severely damaged due to liquefaction. Fissures parallel to the road and lateral spreading are occurred. At the sand bar and marsh, liquefaction occurred in the areas between the …

Case Histories Of Compacted Clay Liners And Covers For Waste Disposal Facilities, David E. Daniel

International Conference on Case Histories in Geotechnical Engineering

Compacted clay liners and covers are widely used in waste containment units. Case histories in three categories are presented: (1) case histories illustrating compaction, construction, and quality assurance difficulties; (2) case histories involving field hydraulic conductivity testing of large-scale test pads; and (3) case histories involving final cover systems. The case histories illustrate that: (1) compaction criteria should be chosen carefully and with consideration given to how the compaction will be controlled in the field; (2) regulatory roadblocks may defeat sound technical approaches in terms of developing compaction criteria; (3) one can follow ASTM procedures and still get into difficulty …

Design And Observation Of Steep Reinforced Embankments, T. Yamanouchi, N. Fukuda

International Conference on Case Histories in Geotechnical Engineering

Using the design method proposed by R. A. Jewell et al. numerous steep reinforced embankments have been constructed in the authors’ home country since the year 1984. In fact these soil structures are built with the reinforcement of polymer grids (the so-called geogrids invented by F. B. Mercer of U.K.) which have a unique structural composition with high-tensile and low-ductility characteristics. This paper deals with first the development of steep reinforced soil structures and their design method, and then introduces a well-documented case history of steep reinforced embankment. The authors propose a current design method developed on the basis of …

The Kettleman Hills Landfill Failure: A Retrospective View Of The Failure Investigations And Lessons Learned, James K. Mitchell, Mihsiung Chang, Raymond B. Seed

International Conference on Case Histories in Geotechnical Engineering

The sliding stability failure of the Kettleman Hills waste landfill focused attention on several issues related to the safe design and filling of waste repositories, including low strengths between geosynthetic material interfaces in composite liner systems and low interface strength between compacted clay and smooth geomembranes. Waste placement plans must be carefully developed to insure an adequate factor of safety against sliding at all stages of filling. Because of assumptions and uncertainties that remained following the initial failure investigation, model tests, at a scale of 1:150, were done. These tests reproduced the field failure very well and provided insights into …

Man-Made Vibrations And Solutions, K. R. Massarsch

International Conference on Case Histories in Geotechnical Engineering

The generation and propagation of man-made vibrations in the ground is discussed. Emphasis is placed a simplified approach which is used to assess the most important factors, such as wave attenuation, refraction focusing and vibration amplification as a result of resonance. Practical guidelines are presented which can be used to predict vibrations and settlements in the ground. A semi-empirical relationship for the assessment of permissible vibration levels for buildings is proposed. Finally, a new ground vibration isolation method, the gas cushion screen is presented.

Practical Studies Of The Seismic Response Of A Rockfill Dam And A Tailings Impoundment, W. D. Liam Finn

International Conference on Case Histories in Geotechnical Engineering

Two case studies from engineering practice are presented to demonstrate how useful a sophisticated finite element analysis can be in providing a comprehensive understanding of how dams behave during earthquakes. The first example involves determining, from the recorded performance of a rockfill dam, the volume change characteristics of the rockfill which cannot be measured directly. The second example covers the full range of current capability for analysis. It involves dynamic effective stress analysis of a tailings dam to check the triggering of liquefaction and the analysis of post-liquefaction flow deformations.

Discussions And Replies: State Of The Art Papers, Mohamad Hussein, Fred H. Held Iii, C. Mirza, T. M. Davisson

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Third International Conference On Case Histories In Geotechnical Engineering, Multiple Authors

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Evaluation Of Yba2cu3o7-X Bulk Superconductors For High Field Magnet Applications, K. Y. Blohowiak, D. F. Garrigus, T. S. Luhman, K. E. Mccrary, M. Strasik, Ilhan A. Aksay, Fatih Dogan, W. B. Hicks, J. Liu, M. Sarikaya

Materials Science and Engineering Faculty Research & Creative Works

Processing of YBCO single crystals was carried out by solidification of semi-liquid YBCO composition using a seeding technique. Microstructural characterization of the pinning centers was investigated by transmission electron microscopy. Characterization of single crystals was carried out, relating grain size and shape to the corresponding flux profiles. Current densities were calculated based on measured trapped fields. Once circulating currents were established, flux pumping and quenching experiments were conducted. These large single crystals will be incorporated into electromagnetic forming devices for use in the military and commercial aircraft manufacturing and service industries.

Evaluation Of Yba,Cu,O,_, Bulk Superconductors For High Field Magnet Applications, K. Y. Blohowiak, D. F. Garrigus, T. S. Luhman, K. E. Mccrary, M. Strasik, I. A. Aksay, Fatih Dogan, W. B. Hicks, J. Liu, M. Sarikaya

Materials Science and Engineering Faculty Research & Creative Works

Processing of YBCO single crystals was carried out by solidification of semi-liquid YBCO composition using a seeding technique. Microstructural characterization of the pinning centers was investigated by transmission electron microscopy. Characterization of single crystals was carried out, relating grain size and shape to the corresponding flux profiles. Current densities were calculated based on measured trapped fields. Once circulating currents were established, flux pumping and quenching experiments were conducted. These large single crystals will be incorporated into electromagnetic forming devices for use in the military and commercial aircraft manufacturing and service industries.

Terrain Classification In Sar Images Using Principal Components Analysis And Neural Networks, Mahmood R. Azimi-Sadjadi, Saleem Ghaloum, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The development of a neural network-based classifier for classifying three distinct scenes (urban, park and water) from several polarized SAR images of San Francisco Bay area is discussed. The principal component (PC) scheme or Karhunen-Loeve (KL) transform is used to extract the salient features of the input data, and to reduce the dimensionality of the feature space prior to the application to the neural networks. Employing PC scheme along with polarized images used in this study, led to substantial improvements in the classification rates when compared with previous studies. When a combined polarization architecture is used the classification rate for …

Assessment Of 1991 Nehrp Provisions For Nonstructural Components And Recommended Revisions, Tsuteh Soong, Genda Chen, Z. Wu, R. H. Zhang, M. Grigoriu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As one part of the 1994 update effort of the 1991 NEHRP provisions, the seismic design force formulas for nonstructural components as they exist in the 1991 provisions are critically assessed and some of their shortcomings are identified. Various levels of improvements to these formulas are then presented which, on the one hand, preserve the equivalent lateral force format for design applicability and, on the other, correct some of the deficiencies on the basis of analyses, experimental results and observation data from past earthquakes.

Based on different interpretations of the component seismic coefficients as well as different degrees of simplicity …

Ccfss Special Edition Technical Bulletin February 1993, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Technical Bulletins (1993 - 2020)

No abstract provided.

Ccfss News February 1993, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.

In-Plane/Out-Of-Plane Dynamic Racking Tests Of Curtain Wall Glass Elements, James H. Culp

Opportunities for Undergraduate Research Experience Program (OURE)

This report describes a research project that was conducted to examine architectural glass behavior as curtain wall components subjected to earthquake-like dynamic motions. The project was an extension of an earlier pilot study conducted in 1991. The 1991 pilot study dealt only with dynamic racking of the curtain wall in its own plane.

The focus of this study was to investigate the effects of adding out-of-plane motions to the previous in-plane motions and to observe the resulting structural performance of various types of architectural glass. Thus, the curtain wall specimens in the current study were racked with motion components both …

Vortex Developments Over An Accelerated Airfoil At High Angles Of Attack, Jacopo A. Frigerio

Opportunities for Undergraduate Research Experience Program (OURE)

Proper control of unsteady separated flow developments over the lifting surfaces of an aircraft may prove to be an effective method of enhancing aerodynamic lift and producing better aircraft performance. Due to the complexity of unsteady flow separation and subsequent flow developments, experimental exploration and observation are essential in providing a source for comparison and verification with theoretical and computational models. In light of these motivations, a new experimental system that is capable of generating wide of range of unsteady flow histories has been developed and employed to visualize flow developments over an airfoil in accelerated-decelerated motion. The paper presents …

The Research, Design And Production Of Cortical Bone Pins And Screws For The Fixation Of Broken Bones In The Hand And Wrist, Ronald P. Holland

Opportunities for Undergraduate Research Experience Program (OURE)

Investigators at the University of Missouri at Rolla have entered into a joint venture with surgeons at Saint Louis University Hospital to develop a superior method of fixing broken bones of the human hand and wrist. This method involves the production of pins and screws from human cortical bone which will be used to fix broken bones for healing. The cortical bone fasteners will provide many advantages to the currently used metal fasteners. To date, prototype fasteners have been developed and are pending mechanical testing as a result of this undergraduate research project. Results of this project potentially include a …

Motorized Throttle Plate, John D. Crawford

Opportunities for Undergraduate Research Experience Program (OURE)

The objective of this project was to develop a throttle plate mechanism that can be used to simulate transient engine operation. This throttle plate was designed so as to regulate the quantity of air flow entering a Port Fuel Injected (PFI) spark ignition engine prior to the combustion of the fuel-air mixture. The throttle plate is linked to a data acquisition system in order to study the port fuel injection characteristics of the fuel-air mixture. This data acquisition system links the throttle plate angular position information to data obtained using a nonintrusive laser based diagnostic technique, therefore enabling the study …

Development Of A Data Acquisition System For Common Velocity Anemometers, Dane P. Drefke

Opportunities for Undergraduate Research Experience Program (OURE)

The objective of this project was to develop a software package that would allow more efficient, accurate, and easier use of wind tunnel data. The software was to receive an analog signal from an array of hot wire anemometers, convert the signal to a digital format, and then process the raw data, converting it into values of properties which have practical value to the user. Unfortunately, due to scheduling conflicts, this project never left the software development stage. The user interface was successfully designed. The signal conversion portion of the package was not completed and the package was never tested.

Behavior Of Bubble Columns, Clint Davison

Opportunities for Undergraduate Research Experience Program (OURE)

In the research program I studied different methods used in mixing gas and liquid in industrial reactors. I was introduced to the bubble column, the airlift reactor, and the bubbling stir tank through text reading, experimentation, and designing. From readings coming from the instrument and observation with my own eyes, I was able to learn much about the flow of particles in tanks such these.

The bubble column and the airlift reactor contain two sections of water flow (riser and downcomer). The riser area has a lower bulk density of fluid because of the rising air bubbles. The downcomer area …

Experimental Investigation On The Longitudinal Stability Of A P51 Mustang Aircraft Model, Erich Fitzpatrick

Opportunities for Undergraduate Research Experience Program (OURE)

This project involved the development of a test model of the P-51 Mustang aircraft and an experimental investigation of its stability. The model was developed to investigate the influence of the main horizontal tail parameters ( tail incidence, position of c.g., stabilizer moment arm,etc.)on the pitching moment around the aircraft’s center of gravity. To accomplish such a task, a test model was designed and fabricated with flat plate and airfoil wing configurations. The tail incidence of the flat plate stabilizer is adjustable over the entire range of positive and negative angles. A rechargeable, electric motor mounted in the fuselage adjusts …

Performance Analysis For The Ccn Collection Apparatus, Deborah K. Bircher

Opportunities for Undergraduate Research Experience Program (OURE)

This paper concerns the performance testing of a system to collect and chemically analyze cloud condensation nuclei (CCN). These are the atmospheric particles which nucleate cloud drops.

The air is humidified by passage through the "haze chamber", consisting of parallel vertical plates that are covered with cotton cloth and are kept wet by water supplied at the top edge. The plates are adiabatic , and should equilibrate in temperature at the wet bulb temperature of the incoming air. Measurements of the plate temperature with eighty thermocouples indicate behavior consistent with theory.

Another part of the system is called the CFD …

Optimizing Energy Usage In A Solar-Powered Vehicle, William R. Macneil

Opportunities for Undergraduate Research Experience Program (OURE)

The University of Missouri - Rolla (UMR) will be entering SUNRAYCE '93 and the World Solar Challenge and expects to excel in these solar-powered car races. Some of the factors involved in winning a race include efficiency, reliability, and high power. All of these are important considerations, but will be ineffective unless appropriately harnessed by a power management scheme appropriate to a race strategy. The power management scheme will be used to efficiently and effectively distribute available power to the car's systems throughout a race day. My goal was to produce a software framework into which the specifications and performance …