Engineering Commons^™

Bayesian Approach For Uncertainty Analysis Of An Urban Storm Water Model And Its Applications To A Heavily Urbanized Watershed, Misgana K. Muleta, Jonathan Mcmillan, Geremew G. Amenu, Steven J. Burian

Civil and Environmental Engineering

The significance of uncertainty analysis (UA) to quantify reliability of model simulations is being recognized. Consequently, literature on parameter and predictive uncertainty assessment of water resources models has been rising. Applications dealing with urban drainage systems are, however, very limited. This study applies formal Bayesian approach for uncertainty analysis of a widely used storm water management model and illustrates the methodology using a highly urbanized watershed in the Los Angeles Basin, California. A flexible likelihood function that accommodates heteroscedasticity, non-normality, and temporal correlation of model residuals has been used for the study along with a Markov-chain Monte Carlo-based sampling scheme. …

Development Of Numerical Model For Predicting Heat Generation And Temperatures In Msw Landfills, James L. Hanson, Nazli Yesiller, Michael T. Onnen, Wei-Lien Liu, Nicolas K. Oettle, Janelle A. Marinos

Civil and Environmental Engineering

A numerical modeling approach has been developed for predicting temperatures in municipal solid waste landfills. Model formulation and details of boundary conditions are described. Model performance was evaluated using field data from a landfill in Michigan, USA. The numerical approach was based on finite element analysis incorporating transient conductive heat transfer. Heat generation functions representing decomposition of wastes were empirically developed and incorporated to the formulation. Thermal properties of materials were determined using experimental testing, field observations, and data reported in literature. The boundary conditions consisted of seasonal temperature cycles at the ground surface and constant temperatures at the far-field …

Veryifying Liquefaction Remediation Beneath And Earth Dam Using Spt And Cpt Based Methods, Ikram Guettaya, Mohamed Ridha El Ouni, Robb Moss

Civil and Environmental Engineering

This paper presents a case study of liquefaction potential assessment for the foundation of an earth dam in Tunisia. An emphasis was made on the exploration of geotechnical conditions and the interpretation of field tests (SPT and CPT) and the results were collected before and after soil densification using the vibrocompaction technique. The assessment of soil liquefaction triggering was made using deterministic and probabilistic simplified procedures. The results indicate that before vibrocompaction the studied area was prone to the liquefaction hazard. However, after vibrocompaction a significant improvement of the soil resistance reduced the liquefaction potential of the sandy foundation soil. …

Transferability And Robustness Of Real-Time Freeway Crash Risk Assessment, Cameron Shew, Anurag Pande, Cornelius Nuworsoo

Civil and Environmental Engineering

This study examines the data from single loop detectors on northbound (NB) US-101 in San Jose, California to estimate real-time crash risk assessment models. Method: The classification tree and neural network based crash risk assessment models developed with data from NB US-101 are applied to data from the same freeway, as well as to the data from nearby segments of the SB US-101, NB I-880, and SB I-880 corridors. The performance of crash risk assessment models on these nearby segments is the focus of this research. Results: The model applications show that it is in fact possible to use the …

Juxtaposing Nasa’S Aeronet Aod With Carb Pm Data Over The San Joaquin Valley To Facilitate Multi-Angle Imaging Spectroradiometer (Misr) Pm Pollution Research, John Kanemoto

STAR Program Research Presentations

Airborne particulate matter (PM) has been shown to increase the risk for asthma, chronic bronchitis, cardiopulmonary complications, and respiratory cell membrane damage/infection/leakage. PM levels are currently analyzed from two perspectives: stationary land-based monitoring (LBM) sites and total Aerosol Optical Depth (AOD) atmospheric column measurements. Both perspectives often leave miles of space between measuring locations and will have a continually increasing cost from introducing/maintaining sites. The Multi-angle Imaging SpectroRadiometer (MISR) satellite team hopes to begin investigating/archiving PM levels comprehensively via inputting MISR AOD measurements into a function/model which predicts the amount of ground level PM.

In the future, multivariable spatial correlations …

Shear-Wave Velocity–Based Probabilistic And Deterministic Assessment Of Seismic Soil Liquefaction Potential, R. Kayen, R. E.S. Moss, E.M. Thompson, R. B. Seed, K. O. Cetin, A. Der Kiureghian, Y. Tanaka, K. Tokimatsu

Civil and Environmental Engineering

Shear-wave velocity (Vs) offers a means to determine the seismic resistance of soil to liquefaction by a fundamental soil property. This paper presents the results of an 11-year international project to gather new Vssite data and develop probabilistic correlations for seismic soil liquefaction occurrence. Toward that objective, shear-wave velocity test sites were identified, and measurements made for 301 new liquefaction field case histories in China, Japan, Taiwan, Greece, and the United States over a decade. The majority of these new case histories reoccupy those previously investigated by penetration testing. These new data are combined with previously published case histories to …

Liquifaction At Strong Motion Stations And In Urayasu City During The 2011 Tohoku-Oki Earthquake, Brady R. Cox, Ross W. Boulanger, Kohji Tokimatsu, Clinton M. Wood, Akio Abe, Scott Ashford, Jennifer Donahue, Kenji Ishihara, Robert Kayen, Kota Katsumata, Tadahiro Kishida, Takaji Kokusho, H. Benjamin Mason, Robb Moss, Jonathan P. Stewart, Kazushi Tohyama, Dimitios Zekkos

Civil and Environmental Engineering

The 2011 M_W = 9.0 Tohoku-oki earthquake generated a large number of unique soil liquefaction case histories, including cases with strong ground motion recordings on liquefiable or potentially liquefiable soils. We have compiled a list of 22 strong motion stations (SMS) where surface evidence of liquefaction was observed and 16 SMS underlain by geologically recent sediments or fills where surface evidence of liquefaction was not observed. Pre-earthquake standard penetration test data and borehole shear wave velocity (V_s) profiles are available for some stations, but critical information, such as grain size distribution and fines plasticity, are often …

Rainwater To Flush Toilets On A Volcano, Robert A. Buchan

STAR Program Research Presentations

Objective: Investigate the feasibility of a rainwater collection system to provide for a sustainable source of non-potable or potable water at a potentially isolated solar observatory site (likely Mauna Loa Observatory in Hawaii).

Introduction: The National Center for Atmospheric Research/High Altitude Observatory (NCAR/HAO) proposes to build a solar observatory comprising a trio of instruments for studying solar coronal magnetism.

Methods: Each square foot of collection surface will experience approximately 0.62 gallons of runoff from 1 inch of rainfall (12 in x 12 in x 1 in = 0.62 gallons). Some water will be lost to evaporation, splashing, overflows, and other …