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Full-Text Articles in Civil and Environmental Engineering

An Innovative Geocentric Decision Support Solution To Comprehensive Planning, Design, Operation, And Management Of Urban Drainage Systems, Paul F. Boulos, Misgana K. Muleta, Chun-Hou Orr, Jun Je Ro May 2006

An Innovative Geocentric Decision Support Solution To Comprehensive Planning, Design, Operation, And Management Of Urban Drainage Systems, Paul F. Boulos, Misgana K. Muleta, Chun-Hou Orr, Jun Je Ro

Civil and Environmental Engineering

Geographic Information System (GIS) is quickly becoming a critical component to develop and sustain asset management for today’s wastewater utilities as most of their data is geographically referenced. This technology offers sophisticated data management and spatial analysis capabilities that can greatly improve and facilitate urban drainage infrastructure modeling and analysis applications. This paper presents a comprehensive GIS-based decision support system that integrates several technologies for use in the effective management of urban stormwater collection systems. It explicitly integrates ESRI ArcGIS geospatial model with advanced hydrologic, hydraulic, and water quality simulation algorithms, nature-based global optimization techniques including genetic algorithms for design …


Using Genetic Algorithms And Particle Swarm Optimization For Optimal Design And Calibration Of Large And Complex Urban Stormwater Management Models, Misgana K. Muleta, Paul F. Boulos, Chun-Hou Orr, Jun Je Ro May 2006

Using Genetic Algorithms And Particle Swarm Optimization For Optimal Design And Calibration Of Large And Complex Urban Stormwater Management Models, Misgana K. Muleta, Paul F. Boulos, Chun-Hou Orr, Jun Je Ro

Civil and Environmental Engineering

Computer models are vital for the evaluation and management of urban drainage systems. Usefulness of these models, however, depends on how well they are calibrated. Properly calibrated models can be used to conceive, evaluate and compare various design improvement alternatives. Unfortunately, calibration and design of urban stormwater models, especially with the commonly used trial-and-error approach, are an expensive, time-consuming process and normally represent the most painful step of a modeling exercise. Their success depends mainly on the engineering expertise of the modeler and budget availability. The effort is complicated by the fact that these models normally necessitate the evaluation of …


Biotreatment Of Synthetic Drill-Cutting Waste In Soil, Laleh Rastegarzadeh, Yarrow Nelson, Todd G. Ririe May 2006

Biotreatment Of Synthetic Drill-Cutting Waste In Soil, Laleh Rastegarzadeh, Yarrow Nelson, Todd G. Ririe

Civil and Environmental Engineering

Oil and gas drilling operations create drill cutting wastes around the world. Drill cutting waste includes synthetic drilling fluids typically consisting of petroleum-based compounds mixed with clay-type materials and water. Biological treatment is an effective means of disposing of drill cutting wastes, but proper biodegradation conditions are critical. In this study biological treatment of drill cutting wastes containing Saraline® (synthetic paraffin mineral oil) was examined using a variety of amendments to study the effect of different conditions on the biodegradability of synthetic drill cutting wastes. Soil was collected from a drilling site in Southeast Asia and soil microcosms were incubated …


Biodegradation Of Hydrocarbons Assisted By Arroyo Willows In Controlled Mesocosms Conducted At The Former Guadalupe Oil Field, Kevin Crossley, Yarrow M. Nelson May 2006

Biodegradation Of Hydrocarbons Assisted By Arroyo Willows In Controlled Mesocosms Conducted At The Former Guadalupe Oil Field, Kevin Crossley, Yarrow M. Nelson

Civil and Environmental Engineering

Abstract of paper presented at conference.


Biodegradation And Toxicity Of Hydrocarbons Along Vertical Transects In A Groundwater Plume, Yarrow M. Nelson, Andrew Lassen, Christopher L. Kitts, Paul Lundegrad, Gonzalo Garcia May 2006

Biodegradation And Toxicity Of Hydrocarbons Along Vertical Transects In A Groundwater Plume, Yarrow M. Nelson, Andrew Lassen, Christopher L. Kitts, Paul Lundegrad, Gonzalo Garcia

Civil and Environmental Engineering

Abstract of paper presented at conference.


Tsunamigenic Probabilistic Fault Displacement Hazard Analysis For Subduction Zones, Robb E.S. Moss, Thaleia Travasarou Apr 2006

Tsunamigenic Probabilistic Fault Displacement Hazard Analysis For Subduction Zones, Robb E.S. Moss, Thaleia Travasarou

Civil and Environmental Engineering

The recent Sumatra earthquake and subsequent tsunami has provoked greater awareness of the hazard posed by coseismic fault displacement associated with sea-floor subduction zones. This catastrophic event has focused renewed efforts on tsunami forecasting, modeling, and detection. Yet the mechanism that causes this type of tsunami, coseismic fault displacement of a sea-floor subduction zone, is still treated deterministically. This paper describes a methodology for probabilistic fault displacement hazard analysis (PFDHA) for a sea-floor subduction zone, and presents example displacement hazard curves for the Cascadia Subduction Zone. The goal of this probabilistic methodology is to quantify the uncertainty and associated hazard …


Incorporating Parameter Uncertainty Into Attenuation Relationships, Robb E.S. Moss, Armen Der Kiureghian Apr 2006

Incorporating Parameter Uncertainty Into Attenuation Relationships, Robb E.S. Moss, Armen Der Kiureghian

Civil and Environmental Engineering

Strong ground motion attenuation relationships estimate the mean and variance of ground shaking as it decreases with distance from an earthquake source. Current relationships use “classical” regression techniques that treat the input variables or parameters as exact, neglecting the uncertainties associated with the measurement of ground acceleration, moment magnitude, site-to-source distance, shear wave velocity, etc. This leads to a poorly constrained estimate of the uncertainty of strong ground motions. This paper discusses the work in progress on; a) estimating the statistics of parameter uncertainty, and b) incorporating the parameter uncertainty into the regression of strong motion attenuation data using a …


Cpt-Based Probabilistic Assessment Of Seismic Soil Liquefaction Initiation, Robb E.S. Moss, R. B. Seed, R. E. Kayen, J. P. Stewart, Armen Der Kiureghian Apr 2006

Cpt-Based Probabilistic Assessment Of Seismic Soil Liquefaction Initiation, Robb E.S. Moss, R. B. Seed, R. E. Kayen, J. P. Stewart, Armen Der Kiureghian

Civil and Environmental Engineering

The correlation of seismic field performance with in situ index test results has been proven to be a reliable method for defining the threshold between liquefaction and non-liquefaction. The objective of this research was to define, in the most accurate and unbiased manner possible, the initiation of seismic soil liquefaction using the cone penetration test (CPT). Contained in this report are the results of this research.

Case histories of occurrence and non-occurrence of soil liquefaction were collected from seismic events that occurred over the past three decades. These were carefully processed to develop improved CPT-based correlations for prediction of the …


Soils Magic: Bringing Civil Engineering To The K–12 Classroom, David J. Elton, James Hanson, David M. Shannon Apr 2006

Soils Magic: Bringing Civil Engineering To The K–12 Classroom, David J. Elton, James Hanson, David M. Shannon

Civil and Environmental Engineering

An investigation was conducted to assess the effectiveness of a series of kindergarten through 12th grade (K–12) educational outreach activities related to civil engineering. In particular, a program called Soils Magic that contains a series of simple geotechnical engineering experiments was delivered in various formats to K–12 students. This paper provides an overview of the Soils Magic program and provides further details of selected experiments from the program. This paper highlights the experiences of various civil engineering professors bringing the program to school children to promote the excitement and accessibility of the engineering profession. Suggestions are provided for conducting successful …


Normalizing The Cpt For Overburden Stress, Robb E.S. Moss, Raymond B. Seed, Richard S. Olsen Mar 2006

Normalizing The Cpt For Overburden Stress, Robb E.S. Moss, Raymond B. Seed, Richard S. Olsen

Civil and Environmental Engineering

Effective overburden stress can have a significant influence on cone penetration test (CPT) measurements. This influence can lead to an incorrect assessment of soil strength/resistance for such purposes as liquefaction triggering analysis. For an accurate measurement of tip and sleeve resistance, unbiased by overburden stress, it is essential to normalize these index measurements appropriately. Presented herein is a comprehensive study reviewing all aspects of CPT normalization. A result of this study is a variable normalization procedure for the CPT that is based on both empirical results and theoretical analysis. This paper presents these results in the form of an improved …


Atms Implementation System For Identifying Traffic Conditions Leading To Potential Crashes, Mohamed Abdel-Aty, Anurag Pande Mar 2006

Atms Implementation System For Identifying Traffic Conditions Leading To Potential Crashes, Mohamed Abdel-Aty, Anurag Pande

Civil and Environmental Engineering

Predicting a crash occurrence is the key to traffic safety. Real-time identification of freeway segments with high crash potential is addressed in this paper. For this study, historical crashes and corresponding traffic-surveillance data from loop detectors were gathered from a 36-mi corridor of Interstate 4 for 4 years. Following an exploratory analysis, two types of logistic-regression models (i.e., simple and multivariate) were developed. It was observed that, although the simple models have the advantage of being tolerant in their data requirements, their classification accuracy was inferior to that of the final multivariate model. Hence, the simple models were used to …


Renewable Materials And Construction Waste Management, Samuel A. Vigil Jan 2006

Renewable Materials And Construction Waste Management, Samuel A. Vigil

Civil and Environmental Engineering

No abstract provided.


Renewable Energy, Samuel A. Vigil Jan 2006

Renewable Energy, Samuel A. Vigil

Civil and Environmental Engineering

No abstract provided.


Comprehensive Analysis Of The Relationship Between Real-Time Traffic Surveillance Data And Rear-End Crashes On Freeways, Anurag Pande, Mohamed Abdel-Aty Jan 2006

Comprehensive Analysis Of The Relationship Between Real-Time Traffic Surveillance Data And Rear-End Crashes On Freeways, Anurag Pande, Mohamed Abdel-Aty

Civil and Environmental Engineering

Rear-end collisions are the single most frequent type of crash on freeways. Their impact on freeway operation is also most noticeable because almost all of them occur during periods of medium to heavy demand. Preliminary explorations of average traffic speeds before a crash measured at loop detector stations surrounding the crash location showed that rear-end crashes can be placed into two mutually exclusive groups: first, those that occur under extended congestion and, second, those that occur with relatively free-flow conditions prevailing 5 to 10 min before the crash. With loop detector data preceding these two groups of rear-end crashes contrasted …


Water Conservation And Wastewater Treatment, Samuel A. Vigil Jan 2006

Water Conservation And Wastewater Treatment, Samuel A. Vigil

Civil and Environmental Engineering

No abstract provided.


The Potential For Real-Time Traffic Crash Prediction, Mohamed Abdel-Aty, Anurag Pande, Liang Y. Hsia, Fathy Abdalla Dec 2005

The Potential For Real-Time Traffic Crash Prediction, Mohamed Abdel-Aty, Anurag Pande, Liang Y. Hsia, Fathy Abdalla

Civil and Environmental Engineering

The development of freeway crash prediction models using intelligent transportation systems (ITS) archived data could be a substantial advancement in the field of real-time traffic management. Such models not only are expected to improve safety but also may go a long way to improve freeway operations by reducing incident-related congestion.

Because there is a need to use real-time traffic data emanating from loop detectors, the approach differs distinctly from previous studies estimating crash frequencies or rates on a certain freeway section through aggregate measures of flow (such as average daily traffic or hourly volumes).

Although the authors try to establish …


Role Of Higher-"Mode" Pushover Analyses In Seismic Analysis Of Buildings, Rakesh K. Goel, Anil K. Chopra Nov 2005

Role Of Higher-"Mode" Pushover Analyses In Seismic Analysis Of Buildings, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

The role of higher-“mode” pushover analyses in seismic analysis of buildings is examined in this paper. It is demonstrated that the higher-“mode” pushover curves reveal plastic hinge mechanisms that are not detected by the first-“mode” or other FEMA-356 force distributions, but these purely local mechanisms are not likely to develop during realistic ground motions in an otherwise regular building without a soft and/or weak story. Furthermore, the conditions necessary for “reversal” of a higher-“mode” pushover curve are examined. It is shown that “reversal” in a higher-“mode” pushover curve occurs after formation of a mechanism if the resultant force above the …


Heat Generation In Municipal Solid Waste Landfills, Nazli Yesiller, James Hanson, Wei-Lien Liu Nov 2005

Heat Generation In Municipal Solid Waste Landfills, Nazli Yesiller, James Hanson, Wei-Lien Liu

Civil and Environmental Engineering

This study was conducted to investigate thermal aspects of municipal solid waste landfills as a function of operational conditions and climatic region. Spatial and temporal distributions of waste temperatures were determined at four landfills located in North America (Michigan, New Mexico, Alaska, and British Columbia). Temperatures of wastes at shallow depths (extending to 6 to 8 m depth) and near the edges of a cell (within approximately 20 m) conformed to seasonal temperature variations, whereas steady elevated temperatures (23 to 57°C) with respect to air and ground temperatures were reached at depth and at central locations. Waste temperatures decreased from …


Proactive Real-Time Traffic Safety Implementation Strategy On Freeways, Mohamed Abdel-Aty, Anurag Pande, Nizam Uddin Oct 2005

Proactive Real-Time Traffic Safety Implementation Strategy On Freeways, Mohamed Abdel-Aty, Anurag Pande, Nizam Uddin

Civil and Environmental Engineering

Reactive traffic management strategies such as incident detection are becoming less relevant with the advancement of mobile phone usage. Freeway management in the 21st century needs to shift focus toward proactive strategies that include anticipating incidents such as the crashes. Predicting crash occurrences would also be the key to traffic safety. A two-step approach to identify freeway locations with high probability of crashes through real-time traffic surveillance data is presented here. For this study historical crash and corresponding traffic data from loop detectors were gathered from a 58-km (36-mile) corridor of Interstate-4. Following an exploratory analysis two types of …


Identification Of Rear-End Crash Patterns On Instrumented Freeways: A Data Mining Approach, A. Pande, M. Abdel-Aty Sep 2005

Identification Of Rear-End Crash Patterns On Instrumented Freeways: A Data Mining Approach, A. Pande, M. Abdel-Aty

Civil and Environmental Engineering

Data mining is the analysis of large “observational” datasets to find unsuspected relationships that might be useful to the data owner. It typically involves analysis where objectives of the mining exercise have no bearing on the data collection strategy. Freeway traffic surveillance data collected through underground loop detectors is one such “observational” database maintained for various ITS (Intelligent Transportation Systems) applications such as travel time prediction etc. In this research data mining process is used to relate this surrogate measure of traffic conditions (data from freeway loop detectors) with occurrence of rear-end crashes on freeways. The results from this analysis …


Traffic Surveillance From A Safety Perspective: An Its Data Application, M. Abdel-Aty, A. Pande, N. Uddin Sep 2005

Traffic Surveillance From A Safety Perspective: An Its Data Application, M. Abdel-Aty, A. Pande, N. Uddin

Civil and Environmental Engineering

Reactive traffic management strategies such as incident detection are becoming less relevant with the advancement of mobile phone usage. Freeway management in the 21st century needs to shift focus toward proactive strategies that include anticipating incidents such as the crashes. “Predicting” crash occurrences would also be the key to traffic safety. A two-step approach to identify freeway locations with high probability of crashes through real-time traffic surveillance data is presented here. For this study historical crash and corresponding traffic data from loop detectors were gathered from a 58-km (36-mile) corridor of Interstate-4. Following an exploratory analysis two types of …


Integrated Temperature And Gas Analysis At A Municipal Solid Waste Landfill, James L. Hanson, Nazli Yesiller, Laurel A. Kendall Sep 2005

Integrated Temperature And Gas Analysis At A Municipal Solid Waste Landfill, James L. Hanson, Nazli Yesiller, Laurel A. Kendall

Civil and Environmental Engineering

This study is conducted to investigate heat and gas production at a municipal solid waste landfill. Periodic temperature and gas measurements have been taken at approximately 140 locations within the waste mass, liner systems, and cover systems at a midwestern U.S.A. landfill since 1999. Increasing temperatures (1 to 15°C/a) were observed for newly placed wastes whereas steady elevated temperatures (50 to 60°C) were observed in older wastes. Liner temperatures increased at a rate of approximately 2 to 4°C/a and stable elevated temperatures in excess of 30°C were observed after 5.5 years and under 42 m of waste height. Anaerobic decomposition …


Evaluation Of Modal And Fema Pushover Procedures Using Strong-Motion Records Of Buildings, Rakesh K. Goel Aug 2005

Evaluation Of Modal And Fema Pushover Procedures Using Strong-Motion Records Of Buildings, Rakesh K. Goel

Civil and Environmental Engineering

The objective of this investigation is to evaluate the FEMA-356 Nonlinear Static Procedure (NSP) and a recently developed Modal Pushover Analysis (MPA) procedure using recorded motions of four buildings that were damaged during the 1994 Northridge earthquake. For this purpose, displacements and drifts from the FEMA-356 NSP and the MPA procedures are compared with the values “derived” from the recorded motions. It is found that the FEMA-356 NSP typically underestimates the drifts in upper stories and overestimates them in lower stories when compared to the recorded motions. Among the four FEMA-356 distributions considered, the “Uniform” distribution led to the most …


Weathering Effects On Biodegradation And Toxicity Of Hydrocarbons In Groundwater, Marie G. Dreyer, Yarrow M. Nelson, Christopher L. Kitts Jun 2005

Weathering Effects On Biodegradation And Toxicity Of Hydrocarbons In Groundwater, Marie G. Dreyer, Yarrow M. Nelson, Christopher L. Kitts

Civil and Environmental Engineering

This study examined the effect of weathering on hydrocarbon biodegradation and toxicity at a former oil field near Guadalupe, California. Soil and groundwater at this site contains residual diesel-range hydrocarbons formerly used to dilute the viscous crude oil to facilitate pumping (Lundegard and Garcia, 2001). Natural attenuation is being considered at this site as a means of remediating residual hydrocarbons in soil and groundwater. To provide the lines of evidence required for use of natural attenuation at this site, this research was undertaken to determine if the hydrocarbons continue to be biodegradable after extensive weathering in the field. Observed hydrocarbon …


Biodegradation Of Weathered Hydrocarbons In Laboratory Microcosms And Soil Columns Simulating Natural Attenuation Field Conditions, C. Robin Cunningham, Yarrow M. Nelson, Paul Lundegard Jun 2005

Biodegradation Of Weathered Hydrocarbons In Laboratory Microcosms And Soil Columns Simulating Natural Attenuation Field Conditions, C. Robin Cunningham, Yarrow M. Nelson, Paul Lundegard

Civil and Environmental Engineering

Abstract of paper presented at conference.


Microbial Activity Of Soil Following Steam Treatment, Barbara Orchard, Yarrow M. Nelson, Lynne Maloney, Christopher L. Kitts, Paul Lundegard Jun 2005

Microbial Activity Of Soil Following Steam Treatment, Barbara Orchard, Yarrow M. Nelson, Lynne Maloney, Christopher L. Kitts, Paul Lundegard

Civil and Environmental Engineering

The effect of steam treatment on subsurface aerobic and anaerobic microbial communities was investigated using multiple microbial assays. Soil samples were gathered and analyzed prior to, one month after, and eight months after a five-month field pilot test of steam injection and extraction. Aerobic soil samples were analyzed by respirometry, plate counts, and direct microscopic counts. Anaerobic microbial activity was examined by monitoring methane generation in anaerobic microcosms with gas chromatography. Respirometry showed pre-steam CO2 production was consistent with natural attenuation, post-steam (one month) CO2 production was below detection, and post-steam (eight months) CO2 production was about …


Improving Safety And Security By Developing A Traffic Accident Prevention System, Mohamed Abdel-Aty, Nizam Uddin, Anurag Pande Jun 2005

Improving Safety And Security By Developing A Traffic Accident Prevention System, Mohamed Abdel-Aty, Nizam Uddin, Anurag Pande

Civil and Environmental Engineering

This research aims at developing accident prediction models to improve freeway safety. Also by reducing incident related congestion on freeways, response and evacuation times would also be reduced in emergency situations. There are considerable amounts of data that are collected and stored for ITS applications. This data includes speed, volume and occupancy provided by loop detectors. Most of these variables are known to be related to accident occurrence and patterns. Previous work has shown the effect of speed variation and volume on traffic safety. In most of the previous work, average or historical speed and volume data have been used. …


Seismic Response Of Linear And Non-Linear Asymmetric Systems With Non-Linear Fluid Viscous Dampers, Rakesh K. Goel Jun 2005

Seismic Response Of Linear And Non-Linear Asymmetric Systems With Non-Linear Fluid Viscous Dampers, Rakesh K. Goel

Civil and Environmental Engineering

This investigation is concerned with the seismic response of one‐story, one‐way asymmetric linear and non‐linear systems with non‐linear fluid viscous dampers. The seismic responses are computed for a suite of 20 ground motions developed for the SAC studies and the median values examined. Reviewed first is the behaviour of single‐degree‐of‐freedom systems to harmonic and earthquake loading. The presented results for harmonic loading are used to explain a few peculiar trends—such as reduction in deformation and increase in damper force of short‐period systems with increasing damper non‐linearity—for earthquake loading. Subsequently, the seismic responses of linear and non‐linear asymmetric‐plan systems with non‐linear …


Determination Of Surface And Thickness Characteristics Of Textured Geomembranes Using Image Analysis, Nazli Yesiller, Arif Cekic May 2005

Determination Of Surface And Thickness Characteristics Of Textured Geomembranes Using Image Analysis, Nazli Yesiller, Arif Cekic

Civil and Environmental Engineering

Image analysis was used to determine surface topography and thickness of textured geomembranes. Images of cross sections (specimen length × thickness) of geomembranes were obtained at 50× magnification using a digital optical microscope. Thickness was determined as the distance between the top and bottom surfaces along an entire cross section. For surface analysis, profiles of top and bottom surfaces were extracted from the cross section images. Amplitude, spatial, hybrid, and functional texture parameters were determined. Tests were conducted on eleven samples of HDPE and LLDPE geomembranes manufactured by co-extrusion and embossing at varying thicknesses. The geomembranes were classified into three …


Sensitivity And Uncertainty Analysis Coupled With Automatic Calibration For A Distributed Watershed Model, Misgana K. Muleta, John W. Nicklow May 2005

Sensitivity And Uncertainty Analysis Coupled With Automatic Calibration For A Distributed Watershed Model, Misgana K. Muleta, John W. Nicklow

Civil and Environmental Engineering

Distributed watershed models should pass through a careful calibration procedure before they are utilized as a decision making aid in the planning and management of water resources. Although manual approaches are still frequently used for calibration, they are tedious, time consuming, and require experienced personnel. This paper describes an automatic approach for calibrating daily streamflow and daily sediment concentration values estimated by the US Department of Agriculture’s distributed watershed simulation model, Soil and Water Assessment Tool (SWAT). The automatic calibration methodology applies a hierarchy of three techniques, namely screening, parameterization, and parameter sensitivity analysis, at the parameter identification stage of …