Civil and Environmental Engineering Commons^™

A Study Of The Seismic Performance Of Early Multi-Story Steel Frame Structures With Unreinforced Masonry Infill, Kristin Potterton

Master's Theses

Steel frame construction with unreinforced masonry infill walls is a common system found in high-rise structures built in the late nineteenth and early twentieth centuries. Recorded performance of this dual system during seismic events shows that the structures are able to resist a high level of lateral loads without collapse, primarily because a majority of damage is confined to the infill walls instead of the gravity carrying frame. To better understand expected performance of this structural system in different seismic risk regions, a prototypical building was analyzed using modal and nonlinear static procedures based on currently accepted evaluation guidelines. Nonlinear …

Bioflocculation For Control Of Wastewater Pond Microalgae, Daniel Thomas Frost

Master's Theses

Investigates several hypotheses regarding the use of bioflocculation as a harvesting method for wastewater pond microalgae. Research performed on pilot-scale high rate ponds (HRPs) on the California Central Coast.

Thermal Analysis Of Cover Systems In Municipal Solid Waste Landfills, Nazli Yesiller, James Hanson, Nicolas K. Oettle, Wei-Lien Liu

Civil and Environmental Engineering

Cover temperature variations were determined at four municipal solid waste landfills located in different climatic regions in North America: Michigan, New Mexico, Alaska, and British Columbia. Cover temperatures varied seasonally similarly to air temperatures and demonstrated amplitude decrement and phase lag with depth. Elevated temperatures in the underlying wastes resulted in warmer temperatures and low frost penetration in the covers compared to surrounding subgrade soils. The ranges of measured temperatures decreased and average temperatures generally increased (approximately 2°C/m) with depth. The ranges of measured temperatures (T_max−T_min) were 18–30°C and 13–21°C and the average temperatures …

A Computing Approach Using Probabilistic Neural Networks For Instantaneous Appraisal Of Rear-End Crash Risk, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

Computing and information technology has significantly increased the capabilities to collect, store, and analyze freeway traffic surveillance data. The most common forms of such data are collected using the underground loop detectors. In the recent past the potential of using these data for identification of crash-prone conditions has been explored. In the present work, application of probabilistic neural networks (PNN) is explored to identify conditions prone to rear-end crashes on the freeway. PNN is a neural network implementation of the well-documented Bayesian classifier. In this research the rear-end crashes observed on the Interstate-4 corridor in Orlando FL are divided into …

Spatial Variability Of Waste Temperatures In Msw Landfills, James L. Hanson, Nazli Yesiller, Nicolas K. Oettle

Civil and Environmental Engineering

Spatial variability of waste temperatures in MSW landfills was determined over different physical and temporal scales. Data have been obtained at four landfills located in different climatic regions in North America: Alaska, British Columbia, Michigan, and New Mexico. Temperatures were measured using 100 to over 250 sensors at each site. Data were obtained for 5 to 10 year periods at the sites. Temperatures were measured in wastes with a broad range of ages: newly-placed and old (up to 40-year old). The characteristic shape of waste temperature vs. depth relationships consists of a convex temperature profile with maximum temperatures observed at …

Experimental Determination Of Cover Surface Temperature Functions At Msw Landfills, Nicolas K. Oettle, James L. Hanson, Nazli Yesiller

Civil and Environmental Engineering

Cover temperatures were measured at four MSW landfills located in different climatic regions in North America: Michigan, New Mexico, Alaska, and British Columbia. Temperature measurements were made on a weekly basis throughout the depth of the cover profiles extending from the surface into the top layers of the underlying wastes. Bias was produced in the surface temperature data due to the combined effects of the time of day that weekly surface measurements were taken and the high diurnal variations at the surface. Analytical methods were used to obtain representative surface temperature functions for the covers from experimental data. Mean cover …

Role Of Shear Keys In Seismic Behavior Of Bridges Crossing Fault-Rupture Zones, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

This paper examines the role of shear keys at bridge abutments in the seismic behavior of “ordinary” bridges. The seismic responses of bridges subjected to spatially uniform and spatially varying ground motions for three shear-key conditions—nonlinear shear keys that break off and cease to provide transverse restraint if deformed beyond a certain limit; elastic shear keys that do not break off and continue to provide transverse restraint throughout the ground shaking; and no shear keys—are examined. Results show that seismic demands for a bridge with nonlinear shear keys can generally be bounded by the demands of a bridge with elastic …

Predicting The Seismic Behavior Of The Dywidag Ductile Connector (Ddc) Precast Concrete System, Elizabeth Mary Kenyon

Master's Theses

Structural engineering is heavily dependent on the use of computers. When creating a building model using structural analysis software, it is required that the designer have an understanding of the system behavior and the modeling program capabilities.

Some engineers in the Southern California region are taking steps towards incorporating the Dywidag ductile connector (DDC) and super hybrid systems into building practice due to the advantages found in these systems’ construction methods and seismic performance.

As the DDC and super hybrid systems reach industry, the design engineer will need to model these systems using structural analysis programs. This report describes two …

Development Of A Laboratory Based Sustainability Course For Environmental Engineers, Samuel A. Vigil

Civil and Environmental Engineering

An understanding of sustainability is important for all engineering students, but especially for Environmental Engineers who will be taking leadership roles on sustainability issues. This paper will discuss the development of a graduate and senior level course which provides the knowledge, computational, and experimental skills in sustainability for these future engineering leaders. The course includes both lecture and laboratory sections.

Analysis And Calibration Of Rdii And Design Of Sewer Collection Systems, Misgana K. Muleta, Paul F. Boulos

Civil and Environmental Engineering

Excessive wet weather flow resulting from rainfall-derived inflow and infiltration (RDII) is a major source of sanitary sewer overflows (SSOs). SSOs pose serious problem to the public and the environment by causing back up into basements and sewer overflows to streets and rivers. Control of sewer overflows is, therefore, vital to reducing risks to public health and protecting the environment from water pollution. Computer modeling of sewer collection systems plays an important role in determining sound and economical remedial solutions that reduce RDII, improve system integrity, reliability and performance, and avoid overflows. This paper presents a rigorous and efficient three-step …

New Orleans And Hurricane Katrina. Iii: The 17th Street Drainage Canal, R. B. Seed, R. G. Bea, A. Athanasopoulos-Zekkos, G. P. Boutwell, J. D. Bray, C. Cheung, D. Cobos-Roa, L. F. Harder, Jr., Robb E.S. Moss, J. M. Pestana, M. F. Riemer, J. D. Rogers, R. Storesund, X. Vera-Grunauer, J. Wartman

Civil and Environmental Engineering

The failure of the levee and floodwall section on the east bank of the 17th Street drainage canal was one of the most catastrophic breaches that occurred during Hurricane Katrina. It produced a breach that rapidly scoured a flow pathway below sea level, so that after the storm surge had largely subsided, floodwaters still continued to stream in through this breach for the next two and a half days. This particular failure contributed massively to the overall flooding of the Metropolitan Orleans East Bank protected basin. Slightly more than half of the loss of life, and a similar fraction of …

Freeway Work-Zone Crash Analysis And Risk Identification Using Multiple And Conditional Logistic Regression, Rami Harb, Essam Radwan, Xuedong Yan, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

Work-zone safety continues to be a priority and a concern for the Federal Highway Association as well as most state departments of transportation. The main objective of this study is to uncover work-zone freeway crash characteristics to help develop countermeasures that limit work-zones’ hazards. The Florida Crash Records Database for years 2002, 2003, and 2004 was utilized for this study. Conditional logistic regression along with stratified sampling and multiple logistic regression models were estimated to unveil work-zone freeway crash traits. According to the models’ results, roadway geometry, weather condition, age, gender, lighting condition, residence code, and driving under the influence …

Exploration Of Crash Prone Traffic Conditions On Freeways In The Netherlands Using Random Forests, Mohamed Abdel-Aty, Anurag Pande, Abhishek Das, Wiilem Jan Knibbe

Civil and Environmental Engineering

Underground loop detectors are one of the most common traffic surveillance apparatus on freeways. Traffic data obtained from these detectors are used for various ITS (Intelligent Transportation Systems) applications such as travel time estimation and incident detection. In the recent past, however, researchers have been interested in proactive applications of these data. These proactive applications primarily involve real-time crash risk assessment based on analysis of traffic surveillance data observed prior to historical crashes. In this study, we have analyzed the crash data from five freeway sections in the Utrecht region of the Netherlands to identify the traffic conditions significantly associated …

Evaluating Route Diversion As A Strategy For Reduction Of Real-Time Crash Risk On Freeways Using Microscopic Simulation, Vikash V. Gayah, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

The objective of this study is to evaluate route diversion as a strategy for reducing crash risk on freeways using Microsimulation. Traffic simulation environment provides the 'loop detector data' which in turn are the inputs to the models used for real-time crash risk estimation. It has been found that rear-end crashes are more accurately described as occurring within one of two distinct traffic regimes. Hence, the crash risk estimates for rear-end crashes belonging to Regime 1 and Regime 2 are output posterior probabilities from two different models which are not directly comparable. A method was proposed to transform the output …

Analytical And Numerical Methodology For Modeling Temperatures In Landfills, James L. Hanson, Wei-Lien Liu, Nazli Yesiller

Civil and Environmental Engineering

Analytical and numerical approaches have been developed for modeling temperatures in municipal solid waste landfills. Steps for model formulation and details of boundary conditions are described. The formulation was based on a transient conductive heat transfer analysis. Conventional earth temperature theories were modified for landfill systems by incorporating heat generation functions representing biological decomposition of wastes. Finite element analysis was used for general modeling and parametric evaluations. Thermal properties of materials were determined using field observations and data reported in literature. The boundary conditions consisted of seasonal temperature cycles at the ground surface (established using near-surface field measurements) and constant …

Engineering Controlled Low Strength Materials Using Scrap Tire Rubber, Tammie Cheung, Daniel C. Jansen, James L. Hanson

Civil and Environmental Engineering

An investigation was conducted to determine the influence of recycled scrap tire rubber on the engineering properties of controlled low strength material (CLSM). With control over the ultimate compressive strength of CLSMs being key for applications such as backfilling utility trenches where re-excavation is often necessary, incorporation of scrap tire rubber into the CLSM mixture is a viable way to limit the ultimate strength. The work presented includes the results of 27 batches of CLSM, 20 of which included scrap tire rubber. The variables included: cement content, fly ash content, and fractional replacement of sand with scrap tire rubber. Results …

Now Hear This! What All Environmental Engineers Should Know About Noise Control, Harold M. Cota, Mark Bastasch, Roger Wayson, Tracy Thatcher

Civil and Environmental Engineering

Noise is an is an that affects almost everyone. And even though environmental engineers are often called on to deal with noise-related problems, most of them receive little or no academic training in noise control. This primer suggests why all environmental engineers should know something about noise control, what they need to know, and where they can find the necessary information.

Assessing Safety On Dutch Freeways With Data From Infrastructure-Based Intelligent Transportation Systems, Mohamed Abdel-Aty, Anurag Pande, Abhishek Das, Willem Jan Knibbe

Civil and Environmental Engineering

Most freeway traffic surveillance technologies deployed around the world remain infrastructure based, with underground loop detectors being the most common among them. A proactive application for traffic surveillance data recently explored for some freeways in the United States is the estimation of real-time crash risk. The application involves establishing relationships between historical crashes and archived traffic data collected before those crashes. In these studies, crash occurrence on freeway sections has been related to temporal-spatial variation in speed and high lane occupancy. Critical modeling questions that remain unanswered relate to transferability of such an approach. This study attempts to address the …

Understanding The Impact Of A Recent Hurricane On Mobilization Time During A Subsequent Hurricane, Vinayak V. Dixit, Anurag Pande, Essam Radwan, Mohamed Abdel-Aty

Civil and Environmental Engineering

It is not uncommon for a region to be affected by multiple hurricanes in a span of a few weeks. The behavior of the evacuees during a subsequent hurricane in the same season is affected by the damage to the infrastructure and to the vehicles and assets belonging to evacuees, as well as by the psychological impact of the preceding hurricane. One such behavioral aspect that affects traffic-loading rates during a hurricane is the evacuation delay or mobilization time. In this study, "mobilization time for an evacuee" is defined as the difference between the time at which the decision to …

The Viability Of Real-Time Prediction And Prevention Of Traffic Accidents, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

This paper addresses a novel idea of real-time traffic safety improvement on freeways. First by predicting traffic crashes on the freeway mainline using on-line loop detector data, then by proposing ITS remediation strategies to reduce the crash risk in real-time. The results of the predictive models were found to be consistent with the probable mechanisms of crashes under different flow regimes. Using micro-simulation software and the crash potential determined through the models developed in this research to associate traffic characteristics with the risk of a crash occurring, several mitigation strategies were attempted to improve safety in real-time. The before (pre-ITS) …

Characteristics Of Urban Arterial Crashes Relative To Proximity To Intersections And Injury Severity, Abhishek Das, Anurag Pande, Mohamed Abdel-Aty, Joseph B. Santos

Civil and Environmental Engineering

Intersections of an urban arterial corridor may influence crashes that occur even beyond their physical area. This study examines the effect of the gradual change in the distance of intersection influence on crash characteristics that explain injury severity outcomes of arterial crashes. The approach adopted involves simultaneous estimation of two variables: an ordinal variable representing crash-injury severity and a binary variable representing crash location (intersection versus segment crashes). The dichotomy in crash location is based on the threshold distance of intersection influence. Five sets of bivariate simultaneous models were estimated by using five threshold distances of influence varying from 0 …

Discovering Indirect Associations In Crash Data Through Probe Attributes, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

Association analysis is a popular data-mining technique for detecting dependencies in transaction databases. The algorithms for discovery of association rules attempt to find the products that tend to sell together. For this purpose, one can treat crashes as individual transactions and crash characteristics as the "products" part of that transaction to discover patterns of the crash characteristics that tend to coexist. The a priori algorithm to search for association rules employs the lower bound on intersection (i.e., joint) frequency of two crash characteristics to ensure that only significant patterns are discovered. Hence, remarkable associations relating crash characteristics that have joint …

Lipid Productivity Of Algae Grown On Dairy Wastewater As A Possible Feedstock For Biodiesel, Ian C. Woertz

Master's Theses

The objective of this thesis is to develop a biological wastewater treatment system that utilizes algal growth to simultaneously create renewable energy in the form of biodiesel and digester biogas, remove polluting nutrients, and abate greenhouse gases. Research under the Department of Energy Aquatic Species Program during 1978-1996 concluded that cultivating algae for biofuels was cost prohibitive at that time and that an integrated approach should be studied that combined wastewater treatment with algal biofuel production. Nutrient removal, in particular nitrogen and phosphorus, from wastewater is a growing regulatory need and the use of algae cultivation could create a unique …

Evaluation Of Current Nonlinear Static Procedures For Concrete Buildings Using Recorded Strong-Motion Data, Rakesh K. Goel, Charles Chadwell

Civil and Environmental Engineering

This study evaluates current Nonlinear Static Procedures (NSPs) specified in the FEMA356, ASCE-41, ATC-40, and FEMA-440 documents using strong-motion data from reinforced-concrete buildings. For this purpose, three-dimensional computer models of five reinforced concrete buildings – Imperial County Services Building, Sherman Oaks Commercial Building, North Hollywood Hotel, Watsonville Commercial Building, and Santa Barbara Office Building – are developed. When appropriate, springs at the building’s base are included to account for the soil-structure interaction effects. These buildings are selected because they were strongly shaken, several deformed beyond their linear-elastic range, during past earthquakes and their recorded motions are available. The recorded motions …

Evaluation Of Current Nonlinear Static Procedures For Concrete Buildings Using Recorded Strong-Motion Data, Rakesh K. Goel, Charles Chadwell

Civil and Environmental Engineering

This paper evaluates current Nonlinear Static Procedures (NSPs) specified in the FEMA- 356, ASCE-41, ATC-40, and FEMA-440 documents using strong-motion data from reinforcedconcrete buildings. For this purpose, peak roof (or target node) displacements estimated from the NSPs are compared with the value derived from recorded motions. It is shown that: (1) the NSPs either overestimate or underestimate the peak roof displacement for several of the buildings considered in this investigation; (2) the ASCE-41 Coefficient Method (CM), which is based on recent improvements to the FEMA-356 CM suggested in FEMA-440 document, does not necessarily provide better estimate of roof displacement; and …

Multiobjective Optimization For Optimal Design Of Urban Drainage Systems, Misgana K. Muleta, Paul F. Boulos

Civil and Environmental Engineering

Control of sewer overflows, the leading cause of water pollution in the nation’s water bodies, is vital to reducing risks to public health and protecting the environment. The most common solutions for mitigating sewer overflows include adding storage volume, increasing conduit capacity, expanding pumping capacity, and implementation of real time operational controls to more effectively utilize existing system storage. Obviously, comprehensive modeling and analysis of these sewer systems becomes necessary for developing sound cost-effective and reliable solutions for enhancing system integrity and performance to convey sewer flows without causing overflows. However, identification of the optimal remedial solution that effectively circumvents …

Diluent Hydrocarbon Biodegredation In Laboratory Microcosms Using Anoxic Eletctron Acceptors, Meghann Chell, Laleh Rastagarzadeh, Yarrow Nelson

Civil and Environmental Engineering

Abstract of Paper Presented at Conference.

On The Nature Of Over-Dispersion In Motor Vehicle Crash Prediction Models, Sudeshna Mitra, Simon Washington

Civil and Environmental Engineering

Statistical modeling of traffic crashes has been of interest to researchers for decades. Over the most recent decade many crash models have accounted for extra-variation in crash counts—variation over and above that accounted for by the Poisson density. The extra-variation – or dispersion – is theorized to capture unaccounted for variation in crashes across sites. The majority of studies have assumed fixed dispersion parameters in over-dispersed crash models—tantamount to assuming that unaccounted for variation is proportional to the expected crash count. Miaou and Lord [Miaou, S.P., Lord, D., 2003. Modeling traffic crash-flow relationships for intersections: dispersion parameter, functional form, and …

Chemical Composition Of Groundwater Hydrocarbon Mixtures Before And After Aerobic Biodegradation, Eileen Mick, Kevin Crossley, Yarrow Nelson

Civil and Environmental Engineering

No abstract provided.

Construction Superintendent Skill Sets, David E. Gunderson, Philip Barlow, Allan J. Hauck

Construction Management

This is the first of a series of articles reviewing the results of an ongoing qualitative research project designed to document construction superintendent skill sets and develop postsecondary curricula to support superintendent education. Varying views of the role of the superintendent and an historical perspective are presented in a review of literature. The research methodology for the entire project, as well as this first phase, is presented. Data have been coded and analyzed from the interviews with seven superintendents to date and the results of these analyses are provided. Themes that emerged in these interviews include people skills, understanding the …