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Full-Text Articles in Civil and Environmental Engineering

Teaching Reliability At The Undergraduate Level, Robb E.S. Moss Jun 2011

Teaching Reliability At The Undergraduate Level, Robb E.S. Moss

Civil and Environmental Engineering

For Cal Poly's Civil and Environmental Engineering curriculum a stand‐alone introductory course called Engineering Risk Analysis introduces concepts of reliability analysis. This course encompasses all the sub‐disciplines in civil and environmental engineering. After five years of teaching this course there are a number of lessons that may be useful to other instructors including; solving a simple example problem using multiple methods, focusing on the normal and lognormal distributions for a quick preliminary solution, using reliability spreadsheet solutions, and allowing the students to develop their own applications of probabilistic tools. A discussion of the course format, references and resources, pedagogy devices, …


Bounding The Probability Of Failure For Levee Systems, Justin C. Hollenback, Robb E.S. Moss Jun 2011

Bounding The Probability Of Failure For Levee Systems, Justin C. Hollenback, Robb E.S. Moss

Civil and Environmental Engineering

An exact solution for the probability of failure of large complex infrastructure systems is rarely obtainable; however the probability of failure can often be bounded. An example of this type of system is the levee system in the California Bay Delta. Large levee systems often consist of many components arranged in series and parallel sub‐systems. There is the problem of defining component (or reach) length, and therefore the total number of components in the system where component length is dependent on failure mode. Methods of bounding probability of failure based on uni‐, bi‐, and tri‐modal component probability of failure are …


Linking Cyclic Stress And Cyclic Strain Based Methods For Assessment Of Cyclic Liquefaction Triggering In Sands, J. A. Schneider, R. E.S. Moss Jun 2011

Linking Cyclic Stress And Cyclic Strain Based Methods For Assessment Of Cyclic Liquefaction Triggering In Sands, J. A. Schneider, R. E.S. Moss

Civil and Environmental Engineering

Contradictory conclusions may arise when assessing liquefaction resistance of sands based on penetrat1on tests and shear wave velocity. To provide a more unified analysis framework, th1s letter couples cyclic stress and cyclic strain based analysis of liquefaction triggering using site-specific correlations between penetration resistance and small strain shear modulus from shear wave velocity using the seismic cone tests. Cyclic strain theory provides a robust lower limit to liquefaction resistance, and analyses indicate that relatively high ratios of small strain stiffness to penetration resistance lead to high liquefaction resistance at relatively low cyclic stress ratios_ The increased resistance to liquefaction from …


Modeling Erosion And Sedimentation Processes In The Chorro Creek Subwatershed To Evaluate And Develop Effective Watershed Management Approaches, Michael Randall, Misgana K. Muleta May 2011

Modeling Erosion And Sedimentation Processes In The Chorro Creek Subwatershed To Evaluate And Develop Effective Watershed Management Approaches, Michael Randall, Misgana K. Muleta

Civil and Environmental Engineering

The Morro Bay Watershed, located in San Luis Obispo County, California, covers more than 48,000 acres of land and discharges into Morro Bay through the Morro Bay National Estuary (MBNE). The Chorro Creek Subwatershed consists of approximately 30,000 acres of the overall watershed. The MBNE provides an ecosystem that supports a variety of wildlife, from the common sea gull to the endangered sea otter. The estuary is also home to over 200 species of birds. The operational waterfront of the Morro Bay Harbor was and continues to be a strong supporter to the local economy of the City of Morro …


Improving Model Performance Using Dynamic Evaluation And Proper Objective Function, Misgana K. Muleta May 2011

Improving Model Performance Using Dynamic Evaluation And Proper Objective Function, Misgana K. Muleta

Civil and Environmental Engineering

Models have become important decision making aids. Model evaluation (i.e., global sensitivity analysis, calibration and uncertainty analysis), is crucial to improve their prediction accuracy and reduce the likelihood of making decisions that could lead to undesirable policy outcomes. The conventional approach assumes that model parameters are insensitive to season irrespective of the temporal variability of input forcings such as rainfall. This assumption could significantly compromise model performance for low flow seasons and/or high flow seasons depending on the calibration method pursued. This study will demonstrate the advantage of dynamic (seasonal) model evaluation in improving performance compared to the traditional approach. …


Assessment Of Public Perception Of User-Based Fees And Tolls To Finance Transportation Infrastructure Improvements, Anurag Pande, Cornelius Nuworsoo, Adrianna Jordan, Reuben Juster, Carmeron Hunter Shew, Joe Yu Apr 2011

Assessment Of Public Perception Of User-Based Fees And Tolls To Finance Transportation Infrastructure Improvements, Anurag Pande, Cornelius Nuworsoo, Adrianna Jordan, Reuben Juster, Carmeron Hunter Shew, Joe Yu

Civil and Environmental Engineering

With aging infrastructure and declining purchasing power of tax receipts new mechanisms of financing transportation alternatives are gaining increasing interest. Fuel taxes are and have been for some time the primary source of transportation finance in United States. Fuel taxes are fixed amounts that rarely change and which lose purchasing power over time as prices escalate. In addition, improvements in fuel economy can further erode the revenue stream from the gas tax. This study explores the public’s attitude about user based fees collected through tolls that are directed at specific infrastructure projects using the Inland Empire region of California as …


Retesting Of Liquefaction/Nonliquefaction Case Histories From The 1976 Tangshan Earthquake, R. E.S. Moss, R. E. Kayen, L-Y Tong, S-Y Liu, G-J Cai, J. Wu Apr 2011

Retesting Of Liquefaction/Nonliquefaction Case Histories From The 1976 Tangshan Earthquake, R. E.S. Moss, R. E. Kayen, L-Y Tong, S-Y Liu, G-J Cai, J. Wu

Civil and Environmental Engineering

A field investigation was carried out to retest liquefaction and nonliquefaction sites from the 1976 Tangshan Earthquake in China. These sites were carefully investigated in 1978/1979 using standard penetration test (SPT) and cone penetration test (CPT) equipment, however the CPT measurements are obsolete because of the now nonstandard cone that was used at the time. In 2007 a modern cone was mobilized to retest 18 select sites that are particularly valuable because; of the intense ground shaking, high fines content, and/or the site did. Of the sites reinvestigated and carefully processed, 13 are considered accurate representative case histories. Two of …


Assessment Of State Composting Regulations In The United States, Nazli Yesiller, Samuel A. Vigil, James L. Hanson Mar 2011

Assessment Of State Composting Regulations In The United States, Nazli Yesiller, Samuel A. Vigil, James L. Hanson

Civil and Environmental Engineering

This investigation was conducted to identify the current "status of state composting regulations in the U.S. using an extensive survey administered to regulators from all 50 states. Questions were included regarding: background information on composting: status of regulations: regulatory details including feedstock specific provisions and regulatory framework with respect to MSW regulations: details regarding type, properties, and amount of materials handled by composting activities; outgoing materials and storage of materials; type of composting facilities: initial development of the regulations; level of rigor of regulations: enforcement and reporting requirements; efficiency and level of satisfaction with regulations: permitting fees; and modifications to …


Seismic Response Of Peaty Organic Soils As A Levee Foundation Material, Robb E.S. Moss, Justin C. Hollenback Mar 2011

Seismic Response Of Peaty Organic Soils As A Levee Foundation Material, Robb E.S. Moss, Justin C. Hollenback

Civil and Environmental Engineering

The dynamic response of peaty organic soils is not well understood but its poor competency as an engineering material is well known. Its use as a foundation material is generally avoided through careful selection of project location, or removal and replacement with more suitable material. In certain situations peaty organic soils are unavoidable because of prior land use and subsequent development of infrastructure. In a delta environment levees are often found to be overlying peaty organic deposits, the California Bay Delta and New Orleans levee systems are two important examples. The Bay Delta is in a seismically active area and …


Shake Table Testing Of Seismic Soil-Foundation-Structure-Interaction, Robb E.S. Moss, Steven Kuo, Victor Crosariol Mar 2011

Shake Table Testing Of Seismic Soil-Foundation-Structure-Interaction, Robb E.S. Moss, Steven Kuo, Victor Crosariol

Civil and Environmental Engineering

This research involves shake table testing of 1g scale models that mimic the coupled seismic response of a structure on a shallow mat foundation and the foundation soil (termed soil‐foundation‐structure‐interaction or SFSI). In previous research, SFSI effects have been quantified through analytical models, numerical analyses, and limited field data. This research is working towards increasing the amount of empirical data through scale model shake table testing. A suite of earthquake times histories are considered in evaluating a 10th scale soil‐structure model using a flexible wall barrel on a 1‐D shake table. San Francisco Young Bay Mud (YBM) is used …


Real-Time Crash Risk Estimation: Are All Freeways Created Equal?, Anurag Pande, Abhishek Das, Mohamed A. Abdel-Aty, Hany Hassan Jan 2011

Real-Time Crash Risk Estimation: Are All Freeways Created Equal?, Anurag Pande, Abhishek Das, Mohamed A. Abdel-Aty, Hany Hassan

Civil and Environmental Engineering

Underground loop detectors have been recently used by many researchers to investigate the links with real-time crash risk and the traffic data. An issue that has been raised but not explicitly addressed in these studies is how the results from one freeway might transfer to another. This study attempts to look at the relationship between crash risk and real-time traffic variables from a freeway corridor (I4 eastbound in Orlando, FL) and attempts to apply the models to three other freeway corridors (I-4 westbound, and I-95 north and southbound). Traffic data used in the study were collected using loop as well …


Traffic Engineering In A Hybrid Format: More Learning With Less Meeting, Anurag Pande, Joe Grimes Jan 2011

Traffic Engineering In A Hybrid Format: More Learning With Less Meeting, Anurag Pande, Joe Grimes

Civil and Environmental Engineering

In the Civil Engineering curriculum at Cal Poly, CE 421 (Traffic Engineering) course is intended to provide students with details of driver behavior, traffic characteristics, and design considerations for addressing traffic problems. In fall 2008, this class was taught in traditional Face-to-Face (f2f) lecture format. Based on the student feedback received at the end of the quarter and success in achieving learning outcomes, it was determined that the course should be more student-centered and there should be a 2-way feedback mechanism between students and instructor throughout the quarter. Based on this evaluation, the course was redesigned and taught in the …


Effects Of Liquefaction-Induced Ground Failure On Bridges, Roads, Railroads And Lifeline Systems, Christian Ledezma, Scott Ashford, Tara Hutchinson, Robb E.S. Moss, Pedro Arduino, Robert Kayen, Scott Olson Jan 2011

Effects Of Liquefaction-Induced Ground Failure On Bridges, Roads, Railroads And Lifeline Systems, Christian Ledezma, Scott Ashford, Tara Hutchinson, Robb E.S. Moss, Pedro Arduino, Robert Kayen, Scott Olson

Civil and Environmental Engineering

No abstract provided.


Landfill Temperatures Under Variable Decomposition Conditions, Nazli Yesiller, James L. Hanson, H. Yoshida Jan 2011

Landfill Temperatures Under Variable Decomposition Conditions, Nazli Yesiller, James L. Hanson, H. Yoshida

Civil and Environmental Engineering

This study was conducted to evaluate temperature, gas, and leachate data at two landfills in similar climatic regions (Detroit, Michigan, USA and Asahikawa, Hokkaido, Japan) to determine the interrelations between heat production and resulting waste temperatures and gas and leachate levels in landfills under variable decomposition conditions. Significant temperature increases occurred under long-term anaerobic conditions. Stable elevated temperatures under anaerobic conditions were observed for wastes at central locations. Seasonal fluctuations in both temperature and gas existed at shallow depths and near perimeter locations. Placement of an overfill of fresh wastes over old wastes affected temperatures, yet did not significantly influence …


Variability And Accuracy Of Target Displacement From Nonlinear Static Procedures, Rakesh K. Goel Jan 2011

Variability And Accuracy Of Target Displacement From Nonlinear Static Procedures, Rakesh K. Goel

Civil and Environmental Engineering

This paper compares the target displacement estimate from four current nonlinear static procedures—FEMA-356 CM, ASCE41 CM, ATC-40 CSM, and FEMA-440 CSM—with the value derived from recorded motions of five strongly shaken reinforced concrete buildings.This comparison provides useful insight into two important questions: (1) how much does the target displacement vary among the four nonlinear static procedures? and (2) can the engineering profession “accurately” predict the response of a real building during an earthquake event using currently available modeling techniques and pushover analysis procedures? It is shown that these procedures may lead to significantly different estimates of the target displacement, particularly …


Comparison Of Base Shears Estimated From Floor Accelerations And Column Shears, Rakesh K. Goel Jan 2011

Comparison Of Base Shears Estimated From Floor Accelerations And Column Shears, Rakesh K. Goel

Civil and Environmental Engineering

This paper compares base shears computed from floor accelerations (inertial base shear) and column shears (structural base shear) for two mid-rise, multistory buildings due to a suite of 30 earthquake ground motions. The presented results demonstrate that the inertial base shear exceeds the structural base shear in the median by 10% to 20% and may exceed the structural base shear by as much as 70% for individual ground motions. Therefore, it is concluded that the inertial base shear computed from strong motion records should be used with caution to estimate the structural base shear.


Assessment Of State Recycling Regulations In The United States, Nazli Yesiller, James L. Hanson, Samuel A. Vigil Oct 2010

Assessment Of State Recycling Regulations In The United States, Nazli Yesiller, James L. Hanson, Samuel A. Vigil

Civil and Environmental Engineering

This investigation was conducted to identify the current status of state recycling regulations in U.S. using an extensive survey. Questions were included regarding: baseline waste generation and recycling trends; recycling regulatory trends; quantitative thresholds; integration of science, engineering, and economic principles; material properties; and legislative status of regulations. The majority of the surveyed states had regulations for recycling activities, which were less strict than solid waste regulations, and required permits for operation of recycling facilities. A low percentage of the states regulated generators, transporters, and handlers and a high percentage regulated recyclers. In general, transfer stations and recycling centers were …


A Realistic Technology And Engineering Assessment Of Algae Biofuel Production, T. J. Lundquist, I. C. Woertz, N. W. T. Quinn, J. R. Benemann Oct 2010

A Realistic Technology And Engineering Assessment Of Algae Biofuel Production, T. J. Lundquist, I. C. Woertz, N. W. T. Quinn, J. R. Benemann

Civil and Environmental Engineering

This report assesses the economics of microalgae biofuels production through an analysis of five production scenarios. These scenarios, or cases, are based on technologies that currently exist or are expected to become available in the near-term, including raceway ponds for microalgae cultivation, bioflocculation for algae harvesting, and hexane for extraction of algae oil. Process flow diagrams, facility site layouts, and estimates for the capital and operations costs of each case were developed de novo. This report also reviews current and developing microalgae biofuel technologies for both oil and biogas production, provides an initial assessment of the US and California …


A Classification Tree Based Modeling Approach For Segment Related Crashes On Multilane Highways, Anurag Pande, Mohamed Abdel-Aty, Abhishek Das Oct 2010

A Classification Tree Based Modeling Approach For Segment Related Crashes On Multilane Highways, Anurag Pande, Mohamed Abdel-Aty, Abhishek Das

Civil and Environmental Engineering

Introduction: This study presents a classification tree based alternative to crash frequency analysis for analyzing crashes on mid-block segments of multilane arterials.

Method: The traditional approach of modeling counts of crashes that occur over a period of time works well for intersection crashes where each intersection itself provides a well-defined unit over which to aggregate the crash data. However, in the case of mid-block segments the crash frequency based approach requires segmentation of the arterial corridor into segments of arbitrary lengths. In this study we have used random samples of time, day of week, and location (i.e., milepost) …


Base Shear Estimated From Floor Accelerations And Column Shears, Rakesh K. Goel Sep 2010

Base Shear Estimated From Floor Accelerations And Column Shears, Rakesh K. Goel

Civil and Environmental Engineering

This paper compares base shear computed from floor accelerations (inertial base shear) and column shears (structural base shear) for several single-degree-of-freedom (SDF) systems and two mid-rise, multi-story buildings due to a suite of 30 earthquake ground motions. The presented results show that the inertial base shear is close to structural base shear in short-period (<1 >sec) SDF systems but may significantly exceed the structural base shear for individual ground motions in longer period (> 1 sec) SDF systems. Furthermore, the inertial base shear exceeds the structural base shear in the median by 10% to 20% and may exceed the structural …


Evaluating Effectiveness Of Best Management Practices To Control Accelerated Sedimentation Of The Morro Bay Estuary, Misgana K. Muleta Aug 2010

Evaluating Effectiveness Of Best Management Practices To Control Accelerated Sedimentation Of The Morro Bay Estuary, Misgana K. Muleta

Civil and Environmental Engineering

The Morro Bay estuary, located on the central Coast of California approximately half way between Los Angeles and San Francisco, is one of the most important wetlands on the west Coast as it supports wide variety of habitats including numerous sensitive and endangered plant and animal species. Various studies have identified accelerated erosion and subsequent sedimentation as a major threat for sustainability of the bay. Watershed disturbances caused by agricultural activities are believed to be one of the major causes of the accelerated erosion and sedimentation. More than 200 conservation practices have been installed in the watershed since the mid-1990 …


Spatial And Temporal Temperature Distributions In Municipal Solid Waste Landfills, James L. Hanson, Nazli Yesiller, Nicolas K. Oettle Aug 2010

Spatial And Temporal Temperature Distributions In Municipal Solid Waste Landfills, James L. Hanson, Nazli Yesiller, Nicolas K. Oettle

Civil and Environmental Engineering

Long-term spatial and temporal variations in temperatures have been investigated in covers, wastes, and liners at four municipal solid waste landfills located in different climatic regions: Alaska, British Columbia, Michigan, and New Mexico. Temperatures were measured in wastes with a broad range of ages from newly placed to old (up to 40 years). The characteristic shape of waste temperature versus depth relationships consisted of a convex temperature profile with maximum temperatures observed at central locations within the middle third fraction of the depth of the waste mass. Lower temperatures were observed above and below this central zone, with seasonal fluctuations …


Compaction Characteristics Of Municipal Solid Waste, James L. Hanson, Nazli Yesiller, Shawna A. Von Stockhausen, Wilson W. Wong Aug 2010

Compaction Characteristics Of Municipal Solid Waste, James L. Hanson, Nazli Yesiller, Shawna A. Von Stockhausen, Wilson W. Wong

Civil and Environmental Engineering

Compaction characteristics of municipal solid waste (MSW) were determined in the laboratory and in the field as a function of moisture content, compactive effort, and seasonal effects. Laboratory tests were conducted on manufactured wastes using modified and 4X modified efforts. Field tests were conducted at a MSW landfill in Michigan on incoming wastes without modifications to size, shape, or composition, using typical operational compaction equipment and procedures. Field tests generally included higher efforts and resulted in higher unit weights at higher water contents than the laboratory tests. Moisture addition to wastes in the field was more effective in winter than …


Simplified Procedures For Seismic Analysis And Design Of Piers And Wharves In Marine Oil And Lng Terminals, Rakesh K. Goel Jun 2010

Simplified Procedures For Seismic Analysis And Design Of Piers And Wharves In Marine Oil And Lng Terminals, Rakesh K. Goel

Civil and Environmental Engineering

No abstract provided.


Geo-Engineering Reconnaissance Of The 2010 Maule, Chile Earthquake, Pedro Arduino, Scott Ashford, Dominic Assimaki, Jonathan Bray, Terry Eldridge, David Frost, Youssef Hashash, Tara Hutchinson, Laurie Johnson, Keith Kelson, Robert Kayen, Christian Ledezma, Robb Moss, George Mylonakis, Scott Olson, Kyle Rollins, Nicholas Sitar, Jonathan Stewart, Alfredo Urzua, Ramon Verdugo, Rob Witter, Nick Zoa May 2010

Geo-Engineering Reconnaissance Of The 2010 Maule, Chile Earthquake, Pedro Arduino, Scott Ashford, Dominic Assimaki, Jonathan Bray, Terry Eldridge, David Frost, Youssef Hashash, Tara Hutchinson, Laurie Johnson, Keith Kelson, Robert Kayen, Christian Ledezma, Robb Moss, George Mylonakis, Scott Olson, Kyle Rollins, Nicholas Sitar, Jonathan Stewart, Alfredo Urzua, Ramon Verdugo, Rob Witter, Nick Zoa

Civil and Environmental Engineering

No abstract provided.


Shake Table Testing To Quantify Seismic Soil Structure Interaction Of Underground Structures, Robb E.S. Moss, Vic Crosariol, Steven Kuo May 2010

Shake Table Testing To Quantify Seismic Soil Structure Interaction Of Underground Structures, Robb E.S. Moss, Vic Crosariol, Steven Kuo

Civil and Environmental Engineering

This research uses shake table testing of scale soil-structure models to mimic the coupled seismic response of underground structures and surrounding/supporting soil (termed soil-structural-interaction or SSI). Currently the seismic design of subways and other critical underground infrastructure rely on little to no empirical data for calibrating numerical simulations. This research is working towards filling that empirical data gap. The research is composed of two phases, the first a validation of the free-field response of a flexible wall barrel filled with model soil, the second a test to measure the “racking” deformations induced in a model subway cross-section embedded in the …


Comparison Of Model Evaluation Methods To Develop A Comprehensive Watershed Simulation Model, Misgana K. Muleta May 2010

Comparison Of Model Evaluation Methods To Develop A Comprehensive Watershed Simulation Model, Misgana K. Muleta

Civil and Environmental Engineering

Comprehensive environmental models such as the Soil and Water Assessment Tool (SWAT) are becoming an integral part of decision making processes for effective planning and management of natural resources. Before their use as decision making aid, however, models must be properly evaluated to improve their prediction accuracy and reduce the likelihood of making decisions that could lead to undesirable policy outcomes. Model evaluation refers to practices such as quality analysis of input data, sensitivity analysis, calibration and verification, and uncertainty analysis. Many methodologies have been developed for model evaluations over the years. One of the major limitations of the existing …


Spatial Variability Of Levees As Measured Using The Cpt, Robb E.S. Moss, J. C. Hollenback, J. Ng May 2010

Spatial Variability Of Levees As Measured Using The Cpt, Robb E.S. Moss, J. C. Hollenback, J. Ng

Civil and Environmental Engineering

The spatial variability of a soil deposit is something that is commonly discussed but difficult to quantify. The heterogeneity as a function of lateral distance can be critical to the design of long engineered structures such as highways, bridges, levees, and other lifelines. This paper presents a methodology for using CPT measurements to quantifying the spatial variability of cone tip resistance along a levee in the California Bay Delta. The results, presented in the form of a general relative variogram, identify the distance at which the maximum spatial variability is achieved for a given soil strata. This information helps define …


Simplified Procedure For Seismic Evaluation Of Piles With Partial-Moment Connection To The Deck In Marine Oil Terminals, Rakesh K. Goel May 2010

Simplified Procedure For Seismic Evaluation Of Piles With Partial-Moment Connection To The Deck In Marine Oil Terminals, Rakesh K. Goel

Civil and Environmental Engineering

This paper presents development of a simplified procedure for seismic evaluation of piles with partial-moment connection typically used in marine oil terminals. The current seismic evaluation procedure of the piles in marine oil terminals includes monitoring material strains specified in the Marine Oil Terminal Engineering and Maintenance Standard (MOTEMS) during the nonlinear static pushover analysis to estimate the displacement capacity of piles. This investigation developed closed-form formulas for estimating the displacement capacity of piles by using a simple pile-deck connection system. The displacement capacity estimated from these formulas ensures that the material stain limits specified in the MOTEMS is not …


Flexural Cracks In Fiber-Reinforced Concrete Beams With Fiber-Reinforced Polymer Reinforcing Bars, Won K. Lee, Daniel C. Jansen, Kenneth B. Berlin, Ian E. Cohen May 2010

Flexural Cracks In Fiber-Reinforced Concrete Beams With Fiber-Reinforced Polymer Reinforcing Bars, Won K. Lee, Daniel C. Jansen, Kenneth B. Berlin, Ian E. Cohen

Civil and Environmental Engineering

Fiber-reinforced polymer (FRP) reinforcing bars have attracted considerable attention for applications where corrosion of steel reinforcement is problematic. Due to the generally low elastic modulus and poor bond characteristics of FRP as compared to steel reinforcing bars, the use of FRP results in larger crack widths under service loads. Fiber-reinforced concrete (FRC) is proposed for use with FRP to reduce crack widths. The work presented herein includes the results from 16 beams tested under four-point bending with either Grade 420 (Grade 60) steel or FRP reinforcing bars, and either plain concrete or FRC. A modified Gergely-Lutz model was applied to …