Civil and Environmental Engineering Commons^™

An Exploration Of Structural Timber Innovation, Simon Beskitt

Williams Honors College, Honors Research Projects

In many undergraduate programs of study, civil and structural engineering students are exposed to introductory material regarding timber construction. The information received in the undergraduate experience typically consists of a brief summary of the basic mechanical properties of wood but does not significantly cover timber design. Much greater emphasis is placed on design practices involving steel and concrete, likely due to their prominence in contemporary building trends in civil engineering. While it is true that wood is one of the older materials in terms of its utilization in structural and architectural design, it is certainly not an antiquated choice. Wood …

Spatial Variations Of The Methanogenic Communities In The Sediments Of Tropical Mangroves, Hongmei Jing, Shunyan Cheung, Zhi Zhou, Chen Wu, Sanjay Nagarajan, Hongbin Liu

The School of Sustainability Engineering and Environmental Engineering (SEE) Faculty Publications

Methane production by methanogens in mangrove sediments is known to contribute significantly to global warming, but studies on the shift of methanogenic community in response to anthropogenic contaminations were still limited. In this study, the effect of anthropogenic activities in the mangrove sediments along the north and south coastlines of Singapore were investigated by pyrosequencing of the mcrA gene. Our results showed that hydrogenotrophic, acetoclastic and methylotrophic methanogens coexist in the sediments. The predominance of the methylotrophic Methanosarcinales reflects the potential for high methane production as well as the possible availability of low acetate and high methylated C-1 compounds as …

Below-Grade Structurla Flexibility Study For Seismic-Resistant, Self-Centering, Concentrically-Braced Frames, Derek A.J. Hauff

Williams Honors College, Honors Research Projects

Self-centering, concentrically braced frames (SC-CBFs) are seismic-resistant lateral-load resisting systems for buildings that increase the lateral drift capacity in comparison to conventional CBFs. Two different substructures were examined on a six-story and a ten-story building to see which below grade structure was more efficient and how the flexibility from the addition of a basement compares to previous research of SC-CBFs structures without basements.

The study was completed in phases: modeling of forces in SAP2000, sizing of structural members, coding of structure into the modeling program Open System for Earthquake Engineering Simulation (OpenSees), and comparison of the output data.

Substructure one …

Cargo Shipping Demand Modeling, Infrastructure Mapping, And Emission Impacts Of Selected U.S. Ports, Robert Coffman Richardson

Electronic Theses and Dissertations

This research included shipping demand modeling, infrastructure asset mapping, and impacts of carbon dioxide (co2) emission. The current volume of imports and exports was reviefor U.S. ports in the east coast, gulf coast, and west coast regions. The import and export of goods is a major part of the U.S. economy, and the volume of cargo handled by U.S. ports is expected to increase in the future as population increases. The major motivation for this thesis was the need for U.S. ports to make plans now to accommodate this expected growth in volume. Ports distribute commodities throughout the U.S., and …

Development Of A Dynamic Coupled Hydro-Geomechanical Code And Its Application To Induced Seismicity, Md Mamun Miah

Electronic Theses and Dissertations

No abstract provided.

Bacteria Prediction For Recreational Waters Through The Use Of Artificial Neural Networks, Christopher Douglas

Electronic Theses and Dissertations

Many scientists and government agencies rely on Fecal Indicator Bacteria (FIB) to determine the risk of exposure to pathogens in water. If there is a presence of these indicator bacteria, pathogenic microorganisms may also be present. These bacteria in recreational water bodies pose a health threat to people if ingested during activities such as swimming or from the consumption of marine life. The most commonly tested FIBs are total coliforms, Fecal coliforms, Escherichia coli, Fecal streptococci, and enterococci. The measurement of bacteria can be time consuming (up to 48 hours) and expensive, creating a difficulty in warning the public of …

Multifunctional Media For Water Quality Control, Spencer Jones

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Strength And Thermal Properties Of Engineered Cementitious Materials, Hannah Maxwell

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Extreme Hydrological Changes In The Southwestern Us Drive Reductions In Water Supply To Southern California By Mid Century, Brianna R. Pagan, Moetasim Ashfaq, Deeksha Rastogi, Donald R. Kendall, Shih-Chieh Kao, Bibi S. Naz, Rui Mei, Jeremy S. Pal

Civil and Environmental Engineering Faculty Works

The Southwestern United States has a greater vulnerability to climate change impacts on water security due to a reliance on snowmelt driven imported water. The State of California, which is the most populous and agriculturally productive in the United States, depends on an extensive artificial water storage and conveyance system primarily for irrigated agriculture, municipal and industrial supply and hydropower generation. Here we take an integrative high-resolution ensemble modeling approach to examine near term climate change impacts on all imported and local sources of water supply to Southern California. While annual precipitation is projected to remain the same or slightly …

Corrosion Protection Systems In Offshore Structures, Hristo Ivanov

Williams Honors College, Honors Research Projects

Corrosion plays a pivotal role in the engineering world. Engineers of all disciplines must consider the dangers that this phenomenon can incur. Interestingly, corrosion mitigation is not a topic that is addressed in most academic curricula. The goal of this paper is to give engineering students a brief introduction into corrosion and some of the prevention techniques commonly used today.

The design of a corrosion protection system for offshore structures is discussed in order to illustrate how these techniques can be utilized even in the most extreme environments. First, the driving force behind corrosion is examined, introducing the basic mechanics …

Estimation Of Submarine Groundwater Discharge Into The Indian River Lagoon, Ashok Pandit, N. Ali, H. Heck, K. Mamoua

Mechanical and Civil Engineering Faculty Publications

A calibrated and validated finite difference numerical model was used to estimate the spatial and temporal distribution of the Meteoric Groundwater Discharge (MGWD) and Submarine Groundwater Discharge (SGD) into a coasted estuary known as the Indian River Lagoon (IRL) at two transects. Specifically, this paper describes the methodology used to determine: a) the quantity of MGWD originating from the mainland and the barrier island, b) the spatial distribution of the SGD into the IRL, c) the groundwater salinity and hydraulic head distribution below the IRL, and d) the regional flow directions of the MGWD and the Oceanic Groundwater Discharge (OGWD) …

Decision Making Of Environmental Engineers On Project Selection, Millicent Amanda Davis

Walden Dissertations and Doctoral Studies

Some environmental engineers do not understand how to perceive profitable opportunities in redeveloping the large number of contaminated brownfield sites in New Jersey. The purpose of this qualitative exploratory case study was to find effective decision-making strategies that help environmental engineers acquire profitable environmental redevelopment projects. The target population consisted of 4 environmental engineers in an environmental organization in Camden County, New Jersey who possessed proven decision-making strategies that helped them acquire profitable environmental redevelopment projects in the past 5 years. The conceptual framework for this study was the multiple criteria decision method (MCDM). Semistructured interviews were conducted with the …

Bs News January/February

Building Services Engineering

No abstract provided.

The Effect Of Community Connectivity On Water And Sanitation Systems In Rural Panama, M.C. Moritz

Dissertations, Master's Theses and Master's Reports

The world has yet to realize universal access to water and sanitation. Various academic and professional fields provide frameworks for understanding water and sanitation access, but none directly consider the impact of community connectivity. Community connectivity refers to the infrastructures linking rural communities with urban centers. These infrastructures fall under the broad categories of transportation, energy, and telecommunication. This paper examines 23 rural Panamanian communities and compares connectivity measures with the functionality of the communities’ rural water and sanitation systems (RWSS). Community connectivity was evaluated with the Community Connectivity Analysis Tool (CCAT), while the water and sanitation systems were evaluated …

Addressing The Impact Of Gavins Point Dam On The Lowermost~1400 Kilometers Of The Missouri River, Gregory Leaphart

Theses and Dissertations

The Missouri River originates in the Rocky Mountains in western Montana and joins the Mississippi River near St. Louis, Missouri. Beginning in the early 1900s, engineering efforts, such as dam construction, channel narrowing, and river alignment, were performed for flood control, navigational purposes, to use of water for agricultural and industrial needs, to produce hydroelectric power and the impounded lakes for recreation. These projects permanently altered the flow and sediment transport regimes in the river and the exchange of sediment with the surrounding floodplain. We focus on the long term effects of dam construction and channel narrowing on approximately the …

Integrating A Simple Traffic Incident Model For Rapid Evacuation Analysis, Andrew J. Collins, R. Michael Robinson, Peter Foytik, Craig Jordan, Barry C. Ezell

VMASC Publications

Road transportation networks are a segment of society's critical infrastructure particularly susceptible to service disruptions. Traffic incidents disrupt road networks by producing blockages and increasing travel times, creating significant impacts during emergency events such as evacuations. For this reason, it is extremely important to incorporate traffic incidents in evacuation planning models. Emergency managers and decision makers need tools that enable rapid assessment of multiple, varied scenarios. Many evacuation simulations require high-fidelity data input making them impractical for rapid deployment by practitioners. Since there is such variation in evacuation types and the method of disruption, evacuation models do not require the …

Early Life History Of Three Pelagic-Spawning Minnows Macrhybopsis Spp. In The Lower Missouri River, T. A. Starks, M. L. Miller, J. M. Long

United States Army Corps of Engineers, Omaha District

Life-history characteristics of age-0 sturgeon chub Macrhybopsis gelida, shoal chub Macrhybopsis hyostoma and sicklefin chub Macrhybopsis meeki were compared using several methods. All Macrhybopsis species consumed mostly midge pupae, but M. meeki had the most general diet (Levins’ index, B=0⋅22) compared with M. hyostoma (B=0⋅02) and M. gelida (B=0⋅09). Morisita’s diet overlap index among species pairs ranged from 0⋅62 to 0⋅97 and was highest between M. hyostoma and M. gelida. Daily ages estimated from lapilli otoliths for each species ranged from 15 to 43 days for M. gelida, 19 to 44 for …

Using Swat To Enhance Watershed-Based Plans To Meet Numeric Water Quality Standards, Aaron R. Mittelstet, Daniel E. Storm, Michael J. White

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The number of states that have adopted numeric nutrient water-quality standards has increased to 23, up from ten in 1998. One state with both stream and reservoir phosphorus (P) numeric water-quality standards is Oklahoma. There were two primary objectives of this research: (1) determine if Oklahoma was meeting the stream and reservoir numeric water-quality standards in the Illinois River and Eucha–Spavinaw watersheds, respectively and (2) identify various combinations of management practices required to meet the water-quality standards. A Soil and Water Assessment Tool (SWAT) model was developed for each watershed. After runoff and P calibration and validation, each model was …

Temporal Dynamics Of Maize Plant Growth, Water Use, And Leaf Water Content Using Automated High Throughput Rgb And Hyperspectral Imaging, Yufeng Ge, Geng Bai, Vincent Stoerger, James C. Schnable

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Automated collection of large scale plant phenotype datasets using high throughput imaging systems has the potential to alleviate current bottlenecks in data-driven plant breeding and crop improvement. In this study, we demonstrate the characterization of temporal dynamics of plant growth and water use, and leaf water content of two maize genotypes under two different water treatments. RGB (Red Green Blue) images are processed to estimate projected plant area, which are correlated with destructively measured plant shoot fresh weight (FW), dry weight (DW) and leaf area. Estimated plant FW and DW, along with pot weights, are used to derive daily plant …

Pumpage Reduction By Using Variable Rate Irrigation To Mine Undepleted Soil Water, Tsz Him Lo, Derek M. Heeren, Derrel Martin, Luciano Mateos, Joe D. Luck, Dean E. Eisenhauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Conventional irrigation schedules are typically based on portions of the field where root zones hold the least available soil water. This leaves undepleted available water in areas with larger water holding capacities. The undepleted water could be used through variable-rate irrigation (VRI) management; however, the benefits of VRI without in-field mapping are unexamined. In this research, the field-averaged amount of undepleted available soil water in the root zone was calculated from the NRCS Soil Survey Geographic database for 49,224 center-pivot irrigated fields in Nebraska. Potential reductions in pumpage from mining undepleted available water were then estimated. Results of the analysis …

Analytical Solution For Speed To Achieve A Desired Operating Point For A Given Fan Or Pump, Michael F. Kocher, Jeyamkondan Subbiah

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Affinity Laws for fans (and pumps) provide a way of determining new fan or pump speed given fan or pump performance curve data and a desired operating point (combination of flow rate and pressure) that does not fall on the curve. However, the affinity law calculations require using a point on the curve (hereafter referred to as the “basic point”) to determine the new speed. Most references regarding the Affinity Laws do not give a clear description of the method for determining the “basic point”, and improper selection of this point can affect the results considerably. This article describes …

In-Field Fuel Use And Load States Of Agricultural Field Machinery, Santosh Pitla, Joe D. Luck, Jared Werner, Nannan Lin, Scott A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The ability to define in-field tractor load states offers the potential to better specify and characterize fuel consumption rate for various field operations. For the same field operation, the tractor experiences diverse load demands and corresponding fuel use rates as it maneuvers through straight passes, turns, suspended operation for adjustments, repair and maintenance, and biomass or other material transfer operations. It is challenging to determine the actual fuel rate and load states of agricultural machinery using force prediction models, and hence, some form of in-field data acquisition capability is required. Controller Area Networks (CAN) available on the current model tractors …

Inter-Row Robot Navigation Using 1d Ranging Sensors, Tyler A. Troyer, Santosh Pitla, Ethan Nutter

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In this paper a fuzzy logic navigation controller for an inter-row agricultural robot is developed and evaluated in laboratory settings. The controller receives input from one-dimensional (1D) ranging sensors on the robotic platform, and operated on ten fuzzy rules for basic row-following behavior. The control system was implemented on basic hardware for proof of concept and operated on a commonly available microcontroller development platform and open source software libraries. The robot platform used for experimentation was a small tracked vehicle with differential steering control. Fuzzy inferencing and defuzzification, step response and cross track error were obtained from the test conducted …

Tractor Hydraulic Power Data Acquisition System, J. B.W. Roeber, Santosh Pitla, Michael F. Kocher, Joe D. Luck, Roger M. Hoy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Tractor hydraulic power is used on a wide range of agricultural implements; however, the availability of operational hydraulic data at points other than full engine throttle position is limited. Operators could utilize this hydraulic data to maximize field efficiency and minimize machinery costs when determining suitable machinery for field operations. A field usable hydraulic test apparatus capable of measuring tractor hydraulic pressure and flow rate data was developed. The goal of this study was to determine if a hydraulic flow and pressure measurement device could be installed on the rear of a tractor to provide implement hydraulic power consumption at …

Quantifying The Fate Of Agricultural Nitrogen In An Unconfined Aquifer: Stream-Based Observations At Three Measurement Scales, Troy E. Gilmore, David P. Genereux, D. Kip Solomon, John E. Solder, Briant A. Kimball, Helena Mitasova, Francois Birgand

Department of Agricultural and Biological Systems Engineering: Faculty Publications

We compared three stream-based sampling methods to study the fate of nitrate in groundwater in a coastal plain watershed: point measurements beneath the streambed, seepage blankets (novel seepage-meter design), and reach mass-balance. The methods gave similar mean groundwater seepage rates into the stream (0.3–0.6 m/d) during two 3–4 day field campaigns despite an order of magnitude difference in stream discharge between the campaigns. At low flow, estimates of flowweighted mean nitrate concentrations in groundwater discharge ([NO^-₃ ]_FWM) and nitrate flux from groundwater to the stream decreased with increasing degree of channel influence and measurement scale, i.e., …

Groundwater Transit Time Distribution And Mean From Streambed Sampling In An Agricultural Coastal Plain Watershed, North Carolina, Usa, Troy E. Gilmore, David P. Genereux, D. Kip Solomon, John E. Solder

Department of Agricultural and Biological Systems Engineering: Faculty Publications

We measured groundwater apparent age (s) and seepage rate (v) in a sandy streambed using point-scale sampling and seepage blankets (a novel seepage meter). We found very similar MTT estimates from streambed point sampling in a 58 m reach (29 years) and a 2.5 km reach (31 years). The TTD for groundwater discharging to the stream was best fit by a gamma distribution model and was very similar for streambed point sampling in both reaches. Between adjacent point-scale and seepage blanket samples, water from the seepage blankets was generally younger, largely because blanket samples contained a fraction of ‘‘young’’ stream …

Comparing Various Hardware/Software Solutions And Conversion Methods For Controller Area Network (Can) Bus Data Collection, Samuel E. Marx, Joe D. Luck, Santosh Pitla, Roger M. Hoy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Various hardware and software solutions exist for collecting Controller Area Network (CAN) bus data. Digital data accuracy could vary based upon different data logging methods (e.g., hardware/software timing, processor timing, etc.). CAN bus data were collected from agricultural tractors using multiple data acquisition solutions to quantify differences among collection methods and demonstrate potential data accumulation rates. Two types of data were observed for this study. The first, CAN bus frame data, represents data collected for each line of hex data sent from an ECU. One issue with frame data is the resulting large file sizes, therefore a second logging format …

Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Brian L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Vegetative filter strips located at the bottom of a hillslope have been shown to substantially reduce nutrients and sediment in runoff. Cropland areas could serve a similar function. However, little scientifically derived information is available to help identify the setback distances required to effectively reduce the transport of contaminants in runoff. The objective of this study was to determine the effects of setback distance and runoff rate on the concentrations and mass transport rates of selected constituents following land application of beef cattle manure to a no-till cropland area. The study site had a residue cover of 8.84 Mg ha-1 …

Impact Of Scale/Resolution On Evapotranspiration From Landsat And Modis Images, Vivek Sharma, Ayse Kilic, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Understanding the role of landscape heterogeneity and its influence on the scaling behavior of surface fluxes as observed by satellite sensors with different spatial resolutions is a critical need to investigate. In this study, the effects of pixel scales on ETc estimation and other parameters that are used to calculate ETc were investigated over different vegetation surfaces in south central Nebraska, USA. Surface Energy Balance System (SEBS) was used to estimate spatially distributed ETc by combining ground-based meteorological data for Landsat and MODIS imagery. The estimated surface energy fluxes were compared and validated to the measured Bowen Ratio Energy Balance …

Removal Of Cattle Manure Constituents In Runoff From No-Till Cropland As Affected By Setback Distance, John E. Gilley, Aaron J. Sindelar, Bryan L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Vegetative filter strips located at the bottom of a hillslope have been shown to substantially reduce nutrients and sediment in runoff. Cropland areas could serve a similar function. However, little scientifically derived information is available to help identify the setback distances required to effectively reduce the transport of contaminants in runoff. The objective of this study was to determine the effects of setback distance and runoff rate on the concentrations and mass transport rates of selected constituents following land application of beef cattle manure to a no-till cropland area. The study site had a residue cover of 8.84 Mg ha …