Civil and Environmental Engineering Commons^™

Heat Management Strategies For Msw Landfills, Nazli Yesiller, James L. Hanson, Kevin B. Kopp, Emma H. Yee

Civil and Environmental Engineering

Heat is a primary byproduct of landfilling of municipal solid waste. Long-term elevated temperatures have been reported for MSW landfills under different operational conditions and climatic regions around the world. A conceptual framework is presented for management of the heat generated in MSW landfills. Three main strategies are outlined: extraction, regulation, and supplementation. Heat extraction allows for beneficial use of the excess landfill heat as an alternative energy source. Two approaches are provided for the extraction strategy: extracting all of the excess heat above baseline equilibrium conditions in a landfill and extracting only a part of the excess heat above …

Geotechnical Effects Of The 2015 Magnitude 7.8 Gorkha, Nepal, Earthquake And Aftershocks, Robb E.S. Moss, Eric M. Thompson, D. Scott Kieffer, Binod Tiwari, Youssef M.A. Hashash, Indra Acharya, Basanta Raj Adhikari, Domniki Asimaki, Kevin B. Clahan, Brian D. Collins, Sachindra Dahal, Randall W. Jibson, Diwakar Khadka, Amy Macdonald, Chris L.M. Madugo, H. Benjamin Mason, Menzer Pehlivan, Deepak Rayamajhi, Sital Uprety

Civil and Environmental Engineering

This article summarizes the geotechnical effects of the 25 April 2015 M 7.8 Gorkha, Nepal, earthquake and aftershocks, as documented by a reconnaissance team that undertook a broad engineering and scientific assessment of the damage and collected perishable data for future analysis. Brief descriptions are provided of ground shaking, surface fault rupture, landsliding, soil failure, and infrastructure performance. The goal of this reconnaissance effort, led by Geotechnical Extreme Events Reconnaissance, is to learn from earthquakes and mitigate hazards in future earthquakes.

Evaluation Of In-Ground Plastic-Hinge Length And Depth For Piles In Marine Oil Terminals, Rakesh K. Goel

Civil and Environmental Engineering

This investigation evaluated the current recommendations for plastic-hinge length and depth for piles in marine oil terminals considering nonlinear pile and soil behavior, as well as two seismic design levels: Level 1 and Level 2. It was found that the plastic-hinge length depends on seismic design level, whereas depth is independent of seismic design level. For pre-stressed concrete piles, the current plastic-hinge length recommendations were generally found to be adequate for seismic design Level 2, but provided much smaller plastic-hinge length for Level 1. For hollow-steel piles, the current plastic-hinge length recommendation was generally found to be adequate for sands, …

Implications Of Variable Waste Placement Conditions For Msw Landfills, Jason T. Cox, Nazli Yesiller, James L. Hanson

Civil and Environmental Engineering

This investigation was conducted to evaluate the influence of waste placement practices on the engineering response of municipal solid waste (MSW) landfills. Waste placement conditions were varied by moisture addition to the wastes at the time of disposal. Tests were conducted at a California landfill in test plots (residential component of incoming wastes) and full-scale active face (all incoming wastes including residential, commercial, and self-delivered components). The short-term effects of moisture addition were assessed by investigating compaction characteristics and moisture distribution and the long-term effects by estimating settlement characteristics of the variably placed wastes. In addition, effects on engineering properties …

Geotechnical Field Reconnaissance: Gorkha (Nepal) Earthquake Of April 25, 2015 And Related Shaking Sequence, Youssef M.A. Hashash, Binod Tiwari, Robb E.S. Moss, Domniki Asimaki, Kevin B. Clahan, D. Scott Kieffer, Doug S. Dreger, Amy Macdonald, Chris M. Madugo, H. Benjamin Mason, Menzer Pehlivan, Deepak Rayamajhi, Indra Acharya, Basanta Adhikari

Civil and Environmental Engineering

The April 25, 2015 Gorkha (Nepal) Earthquake and its related aftershocks had a devastating impact on Nepal. The earthquake sequence resulted in nearly 9,000 deaths, tens of thousands of injuries, and has left hundreds of thousands of inhabitants homeless. With economic losses estimated at several billion US dollars, the financial impact to Nepal is severe and the rebuilding phase will likely span many years. The Geotechnical Extreme Events Reconnaissance (GEER) Association assembled a reconnaissance team under the leadership of D. Scott Kieffer, Binod Tiwari and Youssef M.A. Hashash to evaluate geotechnical impacts of the April 25, 2015 Gorkha Earthquake and …

Waste Heat Generation: A Comprehensive Review, Nazli Yeşiller, James L. Hanson, Emma H. Yee

Civil and Environmental Engineering

A comprehensive review of heat generation in various types of wastes and of the thermal regime of waste containment facilities is provided in this paper. Municipal solid waste (MSW), MSW incineration ash, and mining wastes were included in the analysis. Spatial and temporal variations of waste temperatures, thermal gradients, thermal properties of wastes, average temperature differentials, and heat generation values are provided. Heat generation was influenced by climatic conditions, mean annual earth temperatures, waste temperatures at the time of placement, cover conditions, and inherent heat generation potential of the specific wastes. Time to onset of heat generation varied between months …

Liquefaction Potential Of Recent Fills Versus Natural Sands Located In High-Seismicity Regions Using Shear-Wave Velocity, R. Dobry, T. Abdoun, K.H. Stokoe Ii., R. E.S. Moss, M. Hatton, H. El Ganainy

Civil and Environmental Engineering

The liquefaction potential of clean and silty sands is examined on the basis of the field measurement of the shear-wave velocity, Vs. The starting point is the database of 225 case histories supporting the Andrus-Stokoe Vs-based liquefaction chart for sands, silts, and gravels. Only clean and silty sands with nonplastic fines are considered, resulting in a reduced database of 110 case histories, which are plotted separately by type of deposit. A line of constant cyclic shear strain, γcl≈0.03%, is recommended for liquefaction evaluation of recent uncompacted clean and silty sand fills and earthquake magnitude, Mw=7.5. The geologically recent natural silty …

Routing Strategies For Emergency Management Decision Support Systems During Evacuation, Joseph Yu, Anurag Pande, N. Nezamuddin, Vinayak Dixit, Frances Edwards

Civil and Environmental Engineering

Simulation studies of urban transportation networks have been increasingly applied to evacuation planning. The level of detail provided within a traffic simulation model allows for devising strategies for evacuation and emergency response. In this research, simulation model of downtown San Jose, California, transportation network is developed to evaluate the efficiency of the evacuation process under hypothetical scenarios. Although the scenarios evaluated herein are not exhaustive, they demonstrate the potential of the simulation approach for managing traffic engineering aspects of the emergency response. The scenarios described here include the use of contraflow lanes, traffic incidents on the network, and a modal …

Determination Of Specific Gravity Of Municipal Solid Waste, Nazli Yesiller, James Hanson, Jason Taylor Cox, Danielle E. Noce

Civil and Environmental Engineering

This investigation was conducted to evaluate experimental determination of specific gravity (G_s) of municipal solid waste (MSW). Water pycnometry, typically used for testing soils was adapted for testing MSW using a large flask with 2000 mL capacity and specimens with 100–350 g masses. Tests were conducted on manufactured waste samples prepared using US waste constituent components; fresh wastes obtained prior and subsequent to compaction at an MSW landfill; and wastes obtained from various depths at the same landfill. Factors that influence specific gravity were investigated including waste particle size, compaction, and combined decomposition and stress history. The …

Analyst B: Analysis Of The Utexas1 Passive Linear Surface Wave Dataset, Robb E.S. Moss

Civil and Environmental Engineering

A linear array consisting of 24 1 Hz geophones at 10 m spacing was used to measure the passive surface waves at the UTexas1 site. This paper describes analysis of this dataset using three different methods: ESPAC (extended spatial autocorrelation), f-k (frequency-wavenumber), and ReMi (refraction microtremor). Dispersion curves were developed using each method and the median trends as well as the uncertainty about the medians are compared. The dispersion curves were then individually inverted to estimate shear wave velocity profiles. The inversion results are compared, and a bounded best-estimate shear wave velocity profile is presented. For the site conditions, specific …

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. …

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 …

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. …

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 …

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 …

Dynamic Field Test Of A Model Levee Founded On Peaty Organic Soil Using An Eccentric Mass Shaker, E. T. Reinert, S. J. Brandenberg, J. P. Stewart, R. E.S. Moss

Civil and Environmental Engineering

A dynamic field test of a model levee was performed to study the behavior of very soft and compressible peaty organic soils that commonly underlie levees in the Sacramento / San Joaquin Delta in northern California. This first-of-its-kind test applied dynamic loads to the levee/peat system using a large eccentric mass shaker mounted on the levee crest. Loads from the shaker and the inertia of the levee section are transmitted to the peaty organic soils as base shear stresses, and rotational demands that manifest as normal pressures at the embankment/peat interface. We seek to characterize the transmission of seismic energy …

Dynamic Field Test Of A Model Levee Founded On Peaty Organic Soil Using An Eccentric Mass Shaker, E. T. Reinert, S. J. Brandenberg, J. P. Stewart, R. E.S. Moss

Civil and Environmental Engineering

A dynamic field test of a model levee was performed to study the behavior of very soft and compressible peaty organic soils that commonly underlie levees in the Sacramento / San Joaquin Delta in northern California. This first-of-its-kind test applied dynamic loads to the levee/peat system using a large eccentric mass shaker mounted on the levee crest. Loads from the shaker and the inertia of the levee section are transmitted to the peaty organic soils as base shear stresses, and rotational demands that manifest as normal pressures at the embankment/peat interface. We seek to characterize the transmission of seismic energy …

Coseismic Tectonic Surface Deformation During The 2010 Maule, Chile, MW 8.8 Earthquake, Keith Kelson, Robert C. Witter, Andrés Tassara, Isabelle Ryder, Christian Ledezma, Robb Moss, Laurie Johnson

Civil and Environmental Engineering

Tectonic deformation from the 2010 Maule (Chile) M_w 8.8 earthquake included both uplift and subsidence along about 470 km of the central Chilean coast. In the south, deformation included as much as 3 m of uplift of the Arauco Peninsula, which produced emergent marine platforms and affected harbor infrastructure. In the central part of the deformation zone, north of Constitución, coastal subsidence drowned supratidal floodplains and caused extensive shoreline modification. In the north, coastal areas experienced either slight uplift or no detected change in land level. Also, river-channel deposition and decreased gradients suggest tectonic subsidence may have occurred in …

Model Performance Sensitivity To Objective Function During Automated Calibrations, Misgana Muleta

Civil and Environmental Engineering

Previous studies have reported limitations of the efficiency criteria commonly used in hydrology to describe goodness of model simulations. This study examined sensitivity of model performance to the objective function used during automated calibrations. Nine widely used efficiency criteria were evaluated for their effectiveness as objective function, and goodness of the model predictions were examined using 13 criteria. Two cases (Case I: Using observed streamflow data and Case II: Using simulated streamflow) were considered to accomplish objectives of the study using a widely used watershed model (SWAT) and good-quality field data from a well-monitored experimental watershed. Major findings of the …

Approaches To Control Nitrate Pollution In The San Joaquin Watershed, Misgana K. Muleta, Stephen Clayton

Civil and Environmental Engineering

No abstract provided.

Evaluating Alternative Hydraulic Solutions To Limit Nutrient Contamination Of An Aquifer In Southern California, Jake M. Perry, Misgana K. Muleta

Civil and Environmental Engineering

Many small communities depend on groundwater sources for drinking water and they often use septic tanks for wastewater treatment and disposal. Nitrate and other pollutants leaking from poorly designed septic tank systems can percolate to the aquifers and alter quality of the groundwater. This study describes a groundwater model developed using Visual MODFLOW for an aquifer that is used as a water supply source for the communities of Beaumont and Cherry Valley, CA. The aquifer has been contaminated by nitrates leaking from septic tank systems. The model will assist in clarifying the extent of interactions between nitrate pollutants, percolation from …

A Formal Bayesian Approach For Uncertainty Analysis Of A Watershed Model, Misgana K. Muleta

Civil and Environmental Engineering

Uncertainty analysis (UA) has received substantial attention in water resources during the last decade. Bayesian approaches are often preferred for UA. This study describes a formal Bayesian approach for the assessment of parameter uncertainty and predictive uncertainty using a spatially distributed hydrologic model and will demonstrate its application using data from a well monitored experimental watershed. A Markov-Chain Monte Carlo (MCMC) scheme has been used to sample posterior parameter distributions. A formal, flexible likelihood function that explicitly accounts for heteroscedasticity, temporal correlation and non-normality of simulation residuals has been used to describe closeness of the simulated and observed streamflow. Performance …

Uncertainty Analysis And Calibration Of Swmm Using A Formal, Bayesian Methodology, Misgana K. Muleta

Civil and Environmental Engineering

Importance of uncertainty analysis (UA) to estimate the degree of reliability associated with model predictions is being understood. Consequently, literature that describes various Bayesian methods for the assessment of parameter and model predictive uncertainty has been steadily rising. Applications dealing with urban stormwater management are, however, very limited. This study demonstrates successful application of a formal Bayesian methodology for UA of the U.S. EPA Stormwater Management Model (SWMM), a widely used urban stormwater management model, and illustrates the methodology using a highly urbanized watershed in southern California. DREAM(ZS), a recently developed effective and efficient sampling algorithm, and a generalized, formal …

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

Civil and Environmental Engineering

In lieu of a provided abstract, the first paragraph is provided:

The author agrees with Dr. Pinho about difficulties associated with the use of different damping models in nonlinear dynamic analysis. However, the focus of the original manuscript was to illustrate the difference between base shear estimated from floor accelerations, denoted as inertial base shear, and base shear estimated from column shears, denoted as the structural base shear. The difference between the two base shears exists regardless of the damping model used in the nonlinear analysis. In order to illustrate this conclusion, the Los Angeles building of the original manuscript …

Scale Model Shake Table Testing Of Seismic Earth Pressures In Soft Clay, Robb Moss, R.E. Noche

Civil and Environmental Engineering

There is much uncertainty in seismic earth pressures for basement wall design and retaining wall design in clay soil. The research presented herein uses a scale model testing platform on a 1g shake table to measure the distribution and magnitude of seismic earth pressures for the prototype soil conditions of San Francisco Young Bay Mud (YBM). Similitude scaling of the dynamic soil properties, the wall dimensions, and the input time histories (among other variables) affords accurate modeling of the prototype scale wall. For basement conditions, inertial soil structure interaction (SSI) effects are included in the experiments. Care is taken to …

Use Of Post-Consumer Corrugated Fiberboard As Fine Aggregate Replacement In Controlled Low-Strength Materials, James L. Hanson, Gregory M. Stone, Nazli Yesiller

Civil and Environmental Engineering

This study was conducted to investigate the use of post-con­sumer corrugated board in controlled low-strength material (CLSM) applica­tions. Corrugated fiberboard (termed corrugate), which constitutes a significant fraction of the municipal solid waste stream in the United States (approximately one third by weight), was used as a partial replacement for fine aggregate in CLSM at aggregate replacement ratios ranging from 0 % (i.e., control) to 6 %. The corrugate was fiberized (i.e., repulped) in a blender prior to being mixed with other constituents in the CLSM. The density, air con­tent, and flow consistency of the fresh CLSM were determined, and bleeding …

Improving Model Performance Using Season-Based Evaluation, Misgana Muleta

Civil and Environmental Engineering

Computer models have become vital decision-making tools in many areas of science and engineering including water resources. However, models should be properly evaluated before use to improve the likelihood of making sound decisions based on their results. The model evaluation technique practiced today in hydrology assumes that model parameters are season insensitive and attempts to identify “optimal” values that would describe watershed behavior during dry and wet seasons. This assumption could compromise accuracy of model predictions. This study demonstrates performance improvement that would be achieved when a season-based model evaluation approach is pursued. A global sensitivity analysis (SA) model has …

Quality Of Traffic Flow On Urban Arterial Streets And Its Relationship With Safety, Vinayak V. Dixit, Anurag Pande, Mohamed Abdel-Aty, Abhishek Das, Essam Radwan

Civil and Environmental Engineering

The two-fluid model for vehicular traffic flow explains the traffic on arterials as a mix of stopped and running vehicles. It describes the relationship between the vehicles’ running speed and the fraction of running vehicles. The two parameters of the model essentially represent ‘free flow’ travel time and level of interaction among vehicles, and may be used to evaluate urban roadway networks and urban corridors with partially limited access. These parameters are influenced by not only the roadway characteristics but also by behavioral aspects of driver population, e.g., aggressiveness. Two-fluid models are estimated for eight arterial corridors in Orlando, FL …

Decisive Disaster Debris Management, Nazli Yesiller

Civil and Environmental Engineering

No abstract provided.