Engineering Commons^™

A Case Study On The Use Of Flexible Earth Retaining Structure In Instable Slopes, H. Turan Durgunoglu, Ahmet Sahin, Onder Akcakal

International Conference on Case Histories in Geotechnical Engineering

Recently new highway, motorway and railway projects take place in many developing countries within the aggressive infrastructure investment programme of governments. In rugged topography, engineers face the challenging problems of designing safe and cost effective cuts and fills for these projects especially under seismic loading and marginal stability conditions. Overall stability mechanism and safety of the cut generally controls the design decisions for the relevant section. In addition, because of the construction width limitations, in some mechanically stabilized earth wall projects sufficient width to accommodate the strip lengths of the retaining system cannot be provided. To eliminate all these problems, …

Liquefaction Of Mine Tailings, Vijay K. Puri, Todd R. Kostecki

International Conference on Case Histories in Geotechnical Engineering

Liquefaction of mine tailings is known to occur during cyclic, quasi-static & static loading cases but is still a relatively misunderstood concept because tailings dam failures continue to occur. In the worst case scenario the results are high costs, hindered public perception, environmental cleanup and worst of all, the loss of life. A better understanding of this issue is essential for any engineer associated with the mining and/or geotechnical industry, and in particular tailings dam construction and maintenance. This paper presents the liquefaction concept, some case histories dealing with failure of mine tailings dams, available testing methods and some dated …

Forensic Geotechnical Distress Evaluation Of Damaged Buildings In Alluvial-Loessic Soils; A Case History, Sarfraz Ali, Abdul Qudoos Khan, Usman Zafar, Talha Haider Shehryar

International Conference on Case Histories in Geotechnical Engineering

The city of Hyderabad is a part of lower Indus Basin with arid-tropical climatic conditions. Geologically, the soil deposits near Hyderabad are of alluvial-loessic nature underlain by limestone beds alternating with clay layers. Groundwater is present at shallow depth which fluctuates to even shallower depths during monsoon season in the months of July and August. In recent past, large number of buildings built over shallow foundations in the city suffered structural damages of varying scale in the form of cracks and settlements. Some of these buildings were declared dangerous from safety and stability view point and got vacated by local …

General Report - Session 5, Dimitrios Zekkos, Neven Matasovic, Daniel A. Vellone

International Conference on Case Histories in Geotechnical Engineering

This General Report summarizes the papers submitted to Session 5 titled “Case Histories and Failure of Geological, Rock and Mining Engineering, including Underground Structures and Excavations, and Subsidence of Deltas, Anticipation, Characterization, Design and Construction in the Geological Complexity of Mélanges, Fault Rocks, Weathered Rocks, Boulder Colluvium, Lahars, and Similar Bimrocks (Block-in-Matrix Rocks) and Rock/Soil Mixtures.” A total of eleven papers covering the broad session themes described above were submitted. The geographic distribution of the case histories is listed in Table 1. Overall, five papers were submitted from Asia, two from Africa, two from North America, and two from Europe.

Punch-Through Foundation Failure Of Oil Drilling Platform In The Deltaic Plain Of The Niger River, E. A. J. George, T. J. Atuboyedia, M. Oju, T. E. George

International Conference on Case Histories in Geotechnical Engineering

The deltaic plains of the Niger River are composed mostly of Pleistocene sediments. On the occurrence of low stands of the sea level due to eustatic changes, the sediments were exposed to temperature fluctuations during the Quaternary period, leading to strata sequence generated in these plains that allowed strong layers of soil to overlie weaker layers of the same age. Most of the onshore explorations for oil and gas in Nigeria take place within these plains of the Niger. A well was to be drilled in search of oil and gas in allocation within these plains. As often done, a …

Damage On A Main Gas Pipeline Due To Landslide Of Soils Derived From Volcanic Ashes In Colombia, Gilberto Ch. Rodriguez, Julián V. Rodriguez, Natalia A. Quintero, Jorge E. Villamarín

International Conference on Case Histories in Geotechnical Engineering

In December 2011 a great proportion slope failed affecting the main gas pipeline (20” diameter) that supplies Colombia’s southwest area. The landslide involved materials formed by soils derived from volcanic ashes and residual soils, typical in Colombia’s central zone, which acquired great energy flowing in an avalanche through the natural watercourse. The avalanche generated soil erosion over the torrent banks, generating the watercourse deepening and the deterioration of adjacent slopes over which the pipeline runs. There were identified as landslides triggering aspects the atypical raining period due to “La Niña” climatic phenomenon and the soils removal at the slope base …

Case Study Of Landslides In Kabylia Region, Algeria, Sadaoui Omar, Sadaoui Samir, Bahar Ramdane

International Conference on Case Histories in Geotechnical Engineering

Kabylia is mountainous and coastline region of Algeria. Every year, particularly in the winter, it is affected by landslides displacing an important volume of detritic materials, and causing damages to infrastructures, housing and public facilities. It takes place in geological formations that are particularly favourable to this type of movement, because of the heterogeneity of their facies and the impermeability of some layers. Experience shows that the main cause of the landslides in this region is the combination of several passive and active factors, as geology, morphology, hydrology, climate and anthropic activities. The exceptional rains of winter 2012 triggered a …

Dynamic Properties Of Stabilized Subgrade Clay Soil, Argaw Asha Ashango, Nihar Ranjan Patra

International Conference on Case Histories in Geotechnical Engineering

Expansive soils are fine-grained soils that can undergo a significant volume change due to the variation of water content. A change in the water content of weak subgrade material under the roadway is a cause for the damage of the road pavement. During an earthquake, the soft clay will lose the small shear strength it possesses which causes cracks and movements of the road. In the present study, soil samples were collected from Banda, Uttar Pradesh, India. The study area is at risk for seismic damage due to Himalayan frontal fault earthquakes. The soils samples are highly expansive in nature …

Hydrodynamics Of Pilot-Scale Bubble Columns: Effect Of Internals, Ahmed A. Youssef, Mohamed E. Hamed, Joshua T. Grimes, Muthanna H. Al-Dahhan, Milorad P. Duduković

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Gas Holdup and Bubble Characteristics Are Key Parameters that Affect the Performance of Bubble Columns. an Experimental Study of the Effect of Heat Exchanging Internals on the Gas Holdup, Bubble Dynamics, and their Radial Profiles is Performed. an Air-Water System is Used in a Plexiglas Column 45 Cm (18 In.) in Diameter. Internals Configurations Mimicking Those Typical for the Liquid-Phase Methanol Synthesis and Fischer-Tropsch Process and Covering 5% and 25%, Respectively, of the Total Cross-Sectional Area of the Column, Are Investigated. High Superficial Gas Velocities that Fall within the Churn Turbulent Flow Regime, Which Are of Interest for Most …

Nanoscale Metal Oxide And Supported Metal Catalysts For Li-Air Battery, Kan Huang

Doctoral Dissertations

"The dissertation work focuses on research and development of durable nanoscale catalysts and supports for rechargeable Li-air batteries that use aqueous catholytes. Transition metal oxides, TiO₂ and Nb₂O₅ in particular, were prepared from a sol-gel process in the form of nanocoatings (5~50 nm) on carbon nanotubes (CNTs) and studied as catalyst supports. Carbon doping in the oxides and post annealing significantly increased their electronic conductivity. Pt catalyst on the support with TiO₂ (Pt/c-TiO₂/CNTs) showed a much better oxygen reduction reaction (ORR) activity than a commercial Pt on carbon black (Pt/C). Negligible loss ( …

Scaleup And Hydrodynamics Study Of Gas-Solid Spouted Beds, Shreekanta Basavaraj Aradhya

Doctoral Dissertations

"A thorough understanding of the complex flow structure of gas-solid spouted bed is crucial for design, scale-up and performance. Advanced gas-solid optical probes were developed and used to evaluate different hydrodynamic parameters of spouted beds. These optical probes measure solids concentration, velocity and their time series fluctuations. Since solids concentration needs to be converted to solids holdup through calibration, for meaningful interpretation of results, a novel calibration method was proposed (which is inexpensive and reliable compared to the current reported methods) and validated in the present study. The reported dimensionless groups approach of spouted bed scale-up was assessed and was …

Utilization Of Booster Fans In Underground Mines, Arash Habibi Javanbakht

Masters Theses

"Booster fans are large underground fans that can increase the volumetric efficiency of ventilation systems by balancing the pressure and quantity distribution throughout a mine, reducing leakage and reducing the total power requirement. The objective of this study is to provide potential users of booster fans with the necessary information on the design, installation and operation of main underground fans. The guidelines listed in this paper were formulated based on current U.S. and international standards, safe operating practices developed by the mining industry, and recommendations provided by fan manufacturers. The principles involved in the design and installation of booster fans …

Aggregate Shape Characterization Using Digital Image Processing, Norbert H. Maerz, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aggregates must meet certain specifications to be acceptable in asphalt and concrete applications. Among these are specifications that deal with the various aspects of aggregate shape, including flatness and elongation and aggregate angularity. The current practice for ensuring those specifications is the use of manual-mechanical tests. These tests are time consuming, labor intensive and subjective. In addition, tests such as the compacted or uncompacted voids tests (Figure 1), are taken to be a shape (angularity) indicator, even thought the measured quantify is the void ratio. This report describes a prototype of an automated digital video image analysis system that measures …

Gas Dynamics And Heat Transfer In A Packed Pebble-Bed Reactor For The 4th Generation Nuclear Energy, Rahman Abdulmohsin

Doctoral Dissertations

"Proper analyses of axial dispersion and mixing of the coolant gas flow and heat transport phenomena in the dynamic core of nuclear pebble-bed reactors pose extreme challenges to the safe design and efficient operation of these packed pebble-bed reactors.

The main objectives of the present work are advancing the knowledge of the coolant gas dispersion and extent of mixing and the convective heat transfer coefficients in the studied packed pebble-beds. The study also provides the needed benchmark data for modeling and simulation validation. Hence, a separate effect pilot-plant scale and cold-flow experimental setup was designed, developed and used to carry …

Regional Geomorphic Analysis And Gis Susceptibility Mapping Of Landslides In The Blue Nile And The Tekeze River Basins Of Ethiopia, Elamin Hassan Dai Ismail

Doctoral Dissertations

"The Plateau region of Ethiopia lies within a seismically active continental extensional regime, which is being rapidly incised by the Blue Nile and the Tekeze Rivers. Extremely large landslides pose serious hazards in this highly populated region (>27 million), which is in the process of developing its hydrologic resources. This research sought to develop cost-effective methods to compile regional landslide inventory and landslide susceptibility maps, using geomorphic tools and GIS technologies. This work also sought to evaluate the relationships between landslide dams and knickpoints, caused by channel bed incision from those caused by slope failures, by utilizing identified knickpoints …

A Review Of Pharmaceuticals And Endocrine-Disrupting Compounds: Sources, Effects, Removal, And Detections, Jimoh O. Tijani, Ojo O. Fatoba, Leslie F. Petrik

Mining Engineering Faculty Research & Creative Works

There are growing concerns about the increasing trends of emerging micropollutants in the environment due to their potential negative impacts on natural ecosystems and humans. This has attracted attention from both governmental and non-governmental organizations worldwide. Pharmaceuticals, personal care products, and endocrine disruptors are continuously being released consciously or unconsciously into water sources due to poor regulatory frameworks especially in the developing countries. The effects of these contaminants are poorly known. They are not easily biodegradable and have become an environmental nuisance and public health issue. This has heightened the risk of exposure to their deleterious effects in such countries …

Linear Precoding Of Finite Alphabet Signals In Multi-Antenna Broadcast Channels, Yongpeng Wu, Mingxi Wang, Chengshan Xiao, Zhi Ding, Xiqi Gao

Electrical and Computer Engineering Faculty Research & Creative Works

We investigate the design of linear transmit precoding for multiple-input multiple-output (MIMO) broadcast channels (BC) with finite alphabet input signals. We derive an explicit expression for the achievable rate region of the MIMO BC with discrete constellation inputs, which is generally applicable to cases involving arbitrary user number and arbitrary antenna configurations. for the case where all the users employ the same modulation scheme, we further present a weighted sum rate upper-bound of the MIMO BC with identical transmit precoding matrices. the resulting bound demonstrates a serious performance loss due to multi-user interference for MIMO BC with finite alphabet inputs …

Wide Area Monitoring Of Rotor Angle Based On Synchrophasor Measurements, P. K. Olulope, Ganesh K. Venayagamoorthy, K. A. Folly

Electrical and Computer Engineering Faculty Research & Creative Works

The concept of phasor is designed for steady state and phasor measurement unit (PMU) is based on this concept. Measuring rotor angle therefore during transient has become a challenging task. This paper investigates the possibility of using data from PMU to estimate the internal variables of synchronous generator such as rotor angle of large power system during transient disturbance. the rotor angle is estimated from synchro phasor such as phasor voltage and current as well as their angles. the proposed method is implemented on IEEE 68 bus system. © 2012 IEEE.

The Bridge Newsletter Winter 2012, Missouri University Of Science And Technology

The Bridge Newsletter

-Creating bridge beams that will last 100 years
-Great school, great price
-Recruiting technical minds
-Combatting obesity, diabetes

Ais-Based Coordinated And Adaptive Control Of Generator Excitation Systems For An Electric Ship, Chuan Yan, Ganesh Kumar Venayagamoorthy, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

An artificial immune system (AIS)-Based control of generator excitation systems for the U.S. Navy's electric ship is presented in this paper to solve power quality problems caused by high-energy loads such as direct energy weapons. the coordinated development of the AIS controllers mainly consists of two parts innate immunity (optimal) and adaptive immunity. the parameters of the controllers for the former, to provide optimal performance, are determined simultaneously using particle swarm optimization. for dramatic changes in the ship's power system, adaptive control based on the immune system feedback law is developed. the feedback law adapts the controllers' parameters only during …

Resource Scheduling Under Uncertainty In A Smart Grid With Renewables And Plug-In Vehicles, Ahmed Yousuf Saber, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The power system and transportation sector are our planet's main sources of greenhouse gas emissions. Renewable energy sources (RESs), mainly wind and solar, can reduce emissions from the electric energy sector; however, they are very intermittent. Likewise, next generation plug-in vehicles, which include plug-in hybrid electric vehicles and electric vehicles with vehicletogrid capability, referred to as grid able vehicles (GVs) by the authors, can reduce emissions from the transportation sector. GVs can be used as loads, energy sources (small portable power plants) and energy storage units in a smart grid integrated with renewable energy sources. However, uncertainty surrounds the controllability …

Heat Transfer Coefficients In Mimicked Fischer-Tropsch Slurry Bubble Columns, Chengtian Wu, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

To Provide More Support for Fischer-Tropsch (FT) Slurry Bubble Column Reactor Design, Scale-Up, and Performance, the Effects of Operating Conditions on the Heat Transfer Coefficients Were Investigated in a Mimicked FT Cold Flow System (Compressed Air:C 9-C 11:FT Catalyst Carrier). the Studied Operating Conditions Varied in Superficial Gas Velocity (Up to 0.3 M/s), Pressure (Up to 10 Bar), and Solids Concentration (Up to 25 Vol %). the Effects of These Variables on Heat Transfer Coefficients Are Discussed and Analyzed. the Increase in Pressure Tended to Reduce the Heat Transfer Coefficient, While the Increase in Solids Loading Enhanced the Heat Transfer …

The Bridge Newsletter Spring 2012, Missouri University Of Science And Technology

The Bridge Newsletter

-Light-weight foam could cushion expensive bridge repairs
-New Chancellor
-The house of the future today
-High-tech approach to project management

Dynamic Model-Based Systems Engineering Using Xml Metadata Interchange, Dustin Scott Nottage

Masters Theses

"Designing systems presents an engineer with numerous design choices based on multiple conditions and constraints. Base camp planning must take into account the number of soldiers, the permanency of the base, the location of the base, etc. To help alleviate the complexity of constructing a base camp, a model-based systems engineering approach is used. This method creates and integrates models for all of the facilities that can make a base camp, as well as interactions between facilities and required utilities for each. The goal is to have a camp design, and then solve a system of equations to solve for …

Maximum Power Point Tracking Control Of Hydrokinetic Turbine And Low-Speed High-Thrust Permanent Magnet Generator Design, Hailong Zhou

Masters Theses

"River-based hydrokinetic turbine power generation systems have been studied to introduce an effective energy flow control method. Hydrokinetic turbine systems share a lot of similarities with wind turbine systems in terms of physical principles of operation, electrical hardware, and variable speed capability for optimal energy extraction. A multipole permanent magnet synchronous generator is used to generate electric power because of its ability to reach high power density and high thrust at low speed. A 3-phase diode rectifier is used to convert AC power from the generator into DC power and a boost converter is used to implement energy flow control. …

Effects Of Coal Comminution In Relation To Waterjet And Selected Feed Properties, Yaqing Li

Masters Theses

"The necessity to develop a viable alternative to oil means that the development of coal-water fuels (CWF) has become increasingly important. However, the existing methods of comminution to prepare ultrafine particles for CWF are very inefficient. Consequently, a number of novel methods of comminution have been investigated in order to increase the efficiency of the process.

In this research, a new method of comminution using a high-pressure waterjet has been tested to produce ultrafine particle sizes necessary for efficient CWF process. To establish the fundamental performance of the waterjet mill, the influence of the operational pressure, standoff distance, feed size, …

Glycerin Reformation In High Temperature And Pressure Water, Jason W. Picou

Doctoral Dissertations

"The noncatalytic reformation of glycerin in supercritical water was studied in a Haynes 282 tubular reactor. In order to determine which parameters were the most influential, a 2³ experimental matrix was conducted, with temperatures of 500 and 700⁰C, water/glycerin molar ratios of 3:1 and 13:1, and residence times of 30 and 90 seconds, all at a pressure of 24 MPa. It was found that temperature had the largest effect on the two gasification parameters deemed most important, gasification percentage and hydrogen yield. Based on this, the effect of temperature was further investigated by looking at 5⁰C intervals from 500 to …

Identification Of Starry Milia-Like Cysts In Seborrheic Keratoses And Malignant Melanomas Using Image Processing Techniques, Viswanaath Subramanian

Masters Theses

"Seborrheic keratoses are the most common benign tumors found in older individuals. Seborrheic keratoses are normally benign in nature, but sometimes in a large lesion area of seborrheic keratoses, secondary tumors, or squamous cell carcinoma in situ or malignant melanoma may occur. It has been found that seborrheic keratoses have a few features that distinguish them from melanomas. Milia-like cysts, comedo-like openings and network-like structures are the most prominent features found in seborrheic keratoses. Comedo-like openings are pigmented structures and are mostly oval yellowish, brown or black in appearance. They can also be observed in melanocytic lesions and melanomas. Milia-like …

Shake Table Testing Of A Utility-Scale Wind Turbine, Ian Prowell, Chia Ming Uang, Ahmed Elgamal, J. Enrique Luco, Lanhui Guo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Shake table tests were undertaken on a full-scale wind turbine (65-kW rated power, 22.6-m hub height, and 16-m rotor diameter) using the Network for Earthquake Engineering Simulation Large High Performance Outdoor Shake Table at the University of California, San Diego. Structural response characteristics and modal parameters are presented for base shaking imparted in two configurations, both parallel (configuration 1) and perpendicular (configuration 2) to the axis of rotation of the rotor. Results are summarized for a series of progressively stronger motions imparted in configuration 1, with analysis identifying damage sources leading to an overall loss in stiffness. Two sources of …

Fractal Oxidation Kinetics And Risk Evaluation Of Spontaneous Combustion In Coal Mines, Yutao Zhang

Doctoral Dissertations

"The spontaneous combustion of coal occurs when air supply is sufficient for the oxidation of coal and air velocity is insufficient for the dissipation of generated heat. Spontaneous combustion, if not eradicated immediately, may lead to coal ignition and even a full-blown fire. The fire may engulf a large area and spread further if they are not immediately attended to. This will not only endanger miners and mining operations, but also result in possible mine closures and even fatalities.

Porous structure has a significant effect on coal adsorption and spontaneous combustion. In this research, fractal theory was utilized to quantitatively …