Civil Engineering Commons^™

Numerical Model Water Quality For Hidalgo County, Texas; Main Drainage System, Jose Orvyl Gonzalez, Grimaldo Carrillo, Jungseok Ho

Civil Engineering Faculty Publications

Increasing urbanization, water intake, and human water interaction of drainage canals of the Hidalgo County watershed seals the drainage basin and expands floodplains along the canal-side. Incremental use of drainage systems affects the amounts of nutrients that can cause an exposure to residues of agriculture chemicals, water related parasitic diseases, and fecal diseases. Proper water quality management is crucial for pollutant transport detection, estimation of non-point source discharge, and prediction of pollutant discharge at water endpoints. This research seeks to improve the understanding stormwater quality and quantity that is influenced by the frequency of human-water contacts and associated with treatment …

The Importance Of The “Local” In Walkability, Cynthia Carlson, Semra Aytur, Kevin Gardner, Shannon Rogers

Civil Engineering Faculty Publications

Transportation infrastructure and transportation behaviors consume significant natural resources and are costly to municipalities, states, and the federal government. Small cities, in particular, may find themselves with high costs. Although transportation has been extensively investigated, methods that may enable small cities to act are still lacking. To investigate the influence that neighborhood-level built environment characteristics have on adult personal transportation decisions within small cities, this study combined community-based research, a multi-level analysis of residents, and a case study approach in two (North-Eastern United States) New Hampshire cities, Portsmouth and Manchester. Neighborhood-level physical characteristics were determined using Geographic Information Systems and …

Soil Washing Of Fluorine Contaminated Soil Using Various Washing Solutions, Deok-Hyun Moon, Rae-Hyun Jo, Agamemnon Koutsospyros, Kyung Hoon Cheong, Jeong-Hun Park

Civil Engineering Faculty Publications

Bench-scale soil washing experiments were conducted to remove fluoride from contaminated soils. Five washing solutions including hydrochloric acid (HCl), nitric acid (HNO3), sodium hydroxide (NaOH), sulfuric acid (H2SO4) and tartaric acid (C4H6O6) were tested. The concentration of the washing solutions used ranged from 0.1 M to 3 M with a liquid to solid ratio of 10. The soil washing results showed that the most effective washing solution for the removal of fluoride from contaminated soils was HCl. The highest fluoride removal results of approximately 97% from the contaminated soil were obtained using 3M HCl. The fluoride removal efficiency of the …

Experimental Heat Transfer Study On Green Roofs In A Semiarid Climate During Summer, Roy Issa, Kenneth Leitch, Byungik Chang

Civil Engineering Faculty Publications

An experimental study was conducted on green roofs under the semiarid summer climatic conditions of West Texas to investigate the effect of soil type, moisture content, and the presence of a top soil grass layer on the conductive heat transfer through the roof. Two soil types were investigated: uniform sand and local silt clay. Tests were also conducted on a control roof. A dual-needle heat-pulse sensor was used to conduct thermal property tests on the soils. The tests reveal that unlike sand, the thermal conductivity of silt clay did not increase continuously with soil moisture. Better heat transfer conditions were …

Enhanced Electrokinetic Transport Of Sulfate In Saline Soil, Sung-Ung Jo, Yeon-Jun Shin, Jung-Seok Yang, Deok-Hyun Moon, Agamemnon Koutsospyros, Ki-Tae Baek

Civil Engineering Faculty Publications

The electrokinetic transport of sulfate was investigated as a means of treating and restoring a sulfate-accumulating saline soil. The electrokinetic treatment decreased the electrical conductivity of the soil, an indicator of soil salinity, to 58.6%, 73.1%, and 83.5% for 7, 14 and 21 days, respectively. More than 96% of the chloride and nitrate were removed within 7 days. However, the removal of sulfate was highly influenced by the anode material. An iron anode removed sulfate effectively, whereas, sulfate was hyper-accumulated in the anodic region when an inert anode was used. The iron anode was oxidized in a sacrificial anodic reaction, …

Reflections On Interdisciplinary Sustainability Research With Undergraduate Students, Can B. Aktas

Civil Engineering Faculty Publications

Purpose – The purpose of the article was to convey experiences with pioneering interdisciplinary sustainability research by involving undergraduate students. Experiences with initiating and conducting multiple research projects spanning engineering and sustainability are described, and recommendations for programs and faculty in other institutions of higher education that plan to implement or support similar endeavors are discussed. Design/methodology/approach – The article and presented conclusions are based on three separate research projects, where specific examples as to how those projects were developed as well as challenges and rewards faced during the project are described. Findings – It is concluded that faculty should …

Interfacial Bond Between Reinforcing Fibers And Calcium Sulfoaluminate Cements: Fiber Pullout Characteristics, Robert B. Jewell, Kamyar C. Mahboub, Thomas L. Robl, Arne C. Bathke

Civil Engineering Faculty Publications

The results of an experimental investigation on the influence of the interfacial bond of reinforcing fibers embedded in a calcium sulfoaluminate matrix on the fiber-pullout peak load and energy consumption are presented. Bonding at the fiber-matrix interface plays an important role in controlling the mechanical performance of cementitious composites—in particular, composites formed from sulfate-based systems (calcium sulfoaluminate [CSA] cements), as opposed to the silicate systems found in portland cement. Various types of fibers were selected, including polyvinyl alcohol (PVA), polypropylene, and copper-coated steel. The fibers were embedded in three different matrixes: two sulfate-based cements including one commercially available CSA cement …

A Direct Demand Model Of Departure Time And Mode For Intercity Passenger Trips, Fatemeh Nazari, Seyedehsan Seyedabrishami, Amir Reza Mamdoohi

Civil Engineering Faculty Publications

Travel demand is well announced as a crucial component of transportation planning. This paper aims to develop a direct demand model, denoting a more acceptable abstraction of reality, for intercity passengers in daily work and leisure trips in Tehran province. The model utilizes combined estimation across the data source, collected in 2011, of travelers originating from the city of Tehran and heading toward two destination clusters: intra-province and inter-province. The paper sketches a way to predict simultaneous choice of departure time and travel mode under the influence of zonal (origin, destination, and residence), individual and household socio-demographic, and trip-related variables. …

Developing A University-Wide Course On Sustainability: A Critical Evaluation Of Planning And Implementation, Can B. Aktas, Rosemary Whelan, Howard Stoffer, Edmund Todd, Cindy L. Kern Ph.D.

Civil Engineering Faculty Publications

Sustainability is an issue of increasing importance in today's world. Institutions of higher education are undergoing change towards incorporating sustainable development principles within their teaching, research, service, and community outreach efforts. This article presents a case study of the development and implementation of one such initiative: a university-wide freshman course centered on the topic of sustainability. The objective of the course was to expose freshman students to important sustainability issues in a common course team-taught by faculty from various disciplines. The article presents experiences and recommendations as a guide to administrators, faculty and researchers at other institutions of higher education …

Full-Scale Experimental Modal Analysis Of An Arch Dam: The First Experience In Iran, Reza Tarinejad, Mohammad Taghi Ahmadi, Ronald S. Harichandran

Civil Engineering Faculty Publications

Forced vibration field tests and finite-element studies were conducted on the Shahid Rajaee concrete arch dam in Northern Iran to determine the dynamic properties of the dam–reservoir–foundation system. The first forced vibration tests on the dam were performed with two different types of exciter units, with a limited maximum force, bolted on the dam crest for alternative in-phase and out-of-phase sequencing. Because of an insufficient number of recording sensors, two arrangements of sensors were used to cover sufficient points on the dam crest and one gallery during tests. Two kinds of vibration tests, on–off and frequency sweeping, were carried out …

Electrochemical-Mechanistic Model For Concrete Cover Cracking Due To Corrosion Initiated By Chloride Diffusion, Goli Nossoni, Ronald S. Harichandran

Civil Engineering Faculty Publications

A holistic electrochemical-mechanistic model of the corrosion of steel reinforcing bars inside concrete that accounts for the diffusion of oxygen and moisture into the concrete and rust layers, the densification of rust due to confinement, the flow of rust into the concrete pores, the development of internal pressure due to rust buildup, and cracking of the concrete cover is presented. The relationship between the corrosion current and the pressure buildup due to the corrosion products for different concrete cover thicknesses and concrete quality was calibrated through experiments using an accelerated corrosion test with an applied current. Results from finite-element analysis …

Increasing The Durability Of Piezoelectric Impact-Based Micro Wind Generator In Real Application, Hyun Jun Jung, Yooseob Song, Seong Kwang Hong, Chan Ho Yang, Sung Joo Hwang, Tae Hyun Sung

Civil Engineering Faculty Publications

The purpose of this study is to increase the durability of piezoelectric impact-based micro wind generator (PIMWG) in real application. Using new PIMWG design, numerical simulation, and experimental comparison analysis, we improved the durability of PIMWGs in real application. The experimental results show that the optimized PIMWG generated 2.4 mW (RMS value), and it did not crack within 40 h. In this study, we improved the durability of PIMWGs for real application.

Immobilization Of Lead In Contaminated Firing Range Soil Using Biochar, Deok Hyun Moon, Jae-Woo Park, Yoon-Young Chang, Yong Sik Ok, Sang Soo Lee, Mahtab Ahmad, Agamemnon Koutsospyros, Jeong Hun Park, Kitae Baek

Civil Engineering Faculty Publications

Soybean stover-derived biochar was used to immobilize lead (Pb) in military firing range soil at a mass application rate of 0 to 20 wt.% and a curing period of 7 days. The toxicity characteristic leaching procedure (TCLP) was performed to evaluate the effectiveness of the treatment. The mechanism responsible for Pb immobilization in military firing range soil was evaluated by scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray absorption fine structure (XAFS) spectroscopy analyses. The treatment results showed that TCLP Pb leachability decreased with increasing biochar content. A reduction of over 90 % in Pb leachability was achieved upon …

Response Of An Arch Dam To Non-Uniform Excitation Generated By A Seismic Wave Scattering Model, Reza Tarinejad, Rouzbeh Fatehi Shomeh, Ronald S. Harichandran

Civil Engineering Faculty Publications

Non-uniform ground motions are generated based on a single record available at a site and seismic wave scattering analysis. The Chino Hills 2008 earthquake records at the Pacoima Dam site are used to indicate the accuracy of the method. Dynamic analysis of the Pacoima dam-reservoir-foundation under uniform and non-uniform ground motions is carried out using the EACD-3D2008 software, and the results are compared to recorded responses at different locations on the dam. There is good agreement between computed and recorded displacements of the dam for non-uniform excitation. For uniform excitation, the displacements are underestimated in comparison with those obtained from …

Diffusivity And Sorptivity Of Berea Sandstone Determined Using Neutron Radiography, M. Kang, Chu-Lin Cheng, H. Z. Bilheux, Michael J. Gragg, D. M. Wright, J. M. Lamanna, J. Horita, J. M. Warren

Civil Engineering Faculty Publications

Neutron radiography is increasingly being used to study the dynamics of water movement in variably saturated porous media. It has been applied to visualize water imbibition in both natural and engineered materials, including soil, rock, brick, concrete, and glass. The sorptivity, S, and unsaturated diffusivity, D(θ), are important parameters for describing water movement under partially saturated conditions. Estimates of S and D(θ) have been obtained using a variety of techniques, including neutron imaging. However, we could find no previous reports of such measurements for the Berea sandstone, regardless of the method employed. Berea sandstone is a widespread, …

Social Capital And Walkability As Social Aspects Of Sustainability, Shannon Rogers, Kevin Gardner, Cynthia Carlson

Civil Engineering Faculty Publications

The concepts of sustainability and sustainable development are frequently described as having three main components, sometimes referred to as the three pillars or the triple bottom line: environmental, economic, and social. Because of an historical focus in the sustainability field on correcting environmental problems, much consideration has been given to environmental issues, especially how they interface with economic ones. Frequently mentioned but rarely examined, the social aspects of sustainability have been considered the weakest and least described pillar. After a brief review of existing concepts and theories, this paper uses a case study approach to examine the third pillar more …

Accuracy Analysis Of Parallel Method Based On Non-Overlapping Domain Decomposition Method, Moonho Tak, Yooseob Song, Hye-Kwan Jeon, Taehyo Park

Civil Engineering Faculty Publications

In this paper, an accuracy analysis of parallel method based on non-overlapping domain decomposition method is carried out. In this approach, proposed by Tak et al.(2013), the decomposed subdomains do not overlap each other and the connection between adjacent subdomains is determined via simple connective finite element named interfacial element. This approach has two main advantages. The first is that a direct method such as gauss elimination is available even in a singular problem because the singular stiffness matrix from floating domain can be converted to invertible matrix by assembling the interfacial element. The second is that computational time and …

Forward Prediction Of Height-Averaged Capillary Pressure–Saturation Parameters Using The Bc-Vg Upscaler, Chu-Lin Cheng, Edmund Perfect, R. T. Mills

Civil Engineering Faculty Publications

There is ongoing interest in approaches for upscaling point (e.g., pixel or voxel scale) measurements of soil hydraulic properties to predict column-scale behavior in the laboratory, or even field-scale processes. We have developed the BC-vG Upscaler for estimating the height-averaged capillary pressure–saturation relationship, , for a given porous medium based on equations used in the TrueCell program. Whereas TrueCell inversely estimates point Brooks and Corey (BC) equation parameters from  data, the BC-vG Upscaler uses point BC parameters as inputs for the forward prediction of height-averaged van Genuchten (vG) parameters. The BC-vG Upscaler was verified using previously published, independent point and …

Analysis Of Internet Visitors On Educational Websites, Georgia Romig, Byungik Chang, Kenneth Leitch, Aaron Hunt

Civil Engineering Faculty Publications

This study examines usage patterns of educational websites that employ databases, wikis, and general resources for information sharing and dissemination. To gather data about website usage, a quantitative survey was sent out to students and to the users of an existing educational website. Additionally, participants provided data on learning preferences and practices. Findings from the survey show that users visit an education website for finding information and getting connected to a community. The survey results also show that while communicating information should remain a top priority, educational web sites will need to adapt to an increasing desire for interpersonal communication …

Observations Of Peak Strength Behavior In Csa Cement Mortars, Joshua V. Brien, Kevin R. Henke, Kamyar C. Mahboub

Civil Engineering Faculty Publications

The purpose of this study was to assess the mechanical property performance behavior of calcium sulfoaluminate (CSA) cement mortar when cured at ambient laboratory temperature of ~23°C (73°F) and constant 50% relative humidity for an extended period of time. Four CSA cement mortars were tested. Three CSA cement mortars contained equivalent mass amounts of calcium sulfate; whereas, the fourth mortar contained double the amount of calcium sulfate. The three CSA cement mortars containing constant mass amounts of calcium sulfate differed as the specific type of calcium sulfate varied across the three formulations—one mortar containing solely anhydrite, one mortar contained half …

Effects Of Hinged Dowel System On The Performance Of Concrete Pavement Joints, Alireza Zeinali, Kamyar C. Mahboub, Herbert F. Southgate

Civil Engineering Faculty Publications

Concrete joint failure is a major distress mode in rigid pavements. Improving the joint performance in concrete pavements could yield substantial savings in terms of reduced maintenance and rehabilitation costs. The newly developed Hinged Dowel System (HDS) is a means for transferring loads across the concrete pavement joints. The HDS was patented as a new invention by the United States Patent and Trademark Office, and it is envisioned that it could significantly reduce the potential for joint failure in concrete pavements. The HDS assembly comprises a number of dowel bars and a collective hinge provided at the mid-length of the …

Effective Criteria For Seismic Rehabilitation Planning Of Road Transportation Infrastructures, Mohammadreza Yadollahi, Rosli Mohamad Zin, Sadegh Asgari

Civil Engineering Faculty Publications

While seismic rehabilitation process for road infrastructures has been traditionally based on seismic factors, consideration of non-seismic factors is necessary for reliable project ranking. Non-seismic factors include socioeconomic criteria, determining the value of a project to its users’ community. Based on the information obtained from a questionnaire survey and literature review, this paper identifies a set of effective rehabilitation criteria (ERC) for seismic rehabilitation decision-making to develop a priority index that is applied to determine the rehabilitation priority. The identified RC will then be weighted for four types of road structures including bridges, tunnels, retaining walls, and buildings. The results …

Analysis Of Coal Combustion By-Products Disposal Practices At The San Juan Mine: Hydrologic And Water Quality Issues, Bruce Thomson

Civil Engineering Faculty Publications

Coal Combustion By-Products (CCBs) are generated by the burning of coal for electric power generation and as waste streams from emissions control systems. They consist of bottom ash from the furnaces, fly ash from electrostatic precipitators, and flue gas desulfurization sludge from air pollution scrubbers. Depending on the characteristics of the coal, CCBs may contain high concentrations of metals or other constituents that present a threat to ground or surface water resources if not properly managed. This report describes results of an investigation of CCBs generated by a power plant in northwestern New Mexico. Coal Combustion By-Products from this plant …

Gap Acceptance Parameters For Hcm 2010 Roundabout Capacity Model Applications In Italy, A. Gazzarri, Michael T. Martello, Antonio Pratelli, Reginald R. Souleyrette

Civil Engineering Faculty Publications

This paper deals with the field data observation and successive application of estimation procedures in order to estimate follow-up headway and critical headway at roundabouts. Average follow-up headway and average critical headway are two key parameters in the new roundabout capacity model presented in the 2010 edition of the Highway Capacity Manual (HCM). The HCM 2010 capacity model was developed as an exponential regression model with parameter estimates based on gap acceptance theory. Gap acceptance models are strongly affected by driver behaviour and local habits. Follow-up headways can be field measured, while critical headway cannot be obtained directly. The paper …

Impact Of Lifetime On U.S. Residential Building Lca Results, Can B. Aktas, M. M. Bilec

Civil Engineering Faculty Publications

Purpose: Many life cycle assessment (LCA) studies do not adequately address the actual lifetime of buildings and building products, but rather assume a typical value. The goal of this study was to determine the impact of lifetime on residential building LCA results. Including accurate lifetime data into LCA allows a better understanding of a product’s environmental impact that would ultimately enhance the accuracy of LCA results.

Methods This study focuses on refining the U.S. residential building lifetime, as well as lifetime of interior renovation products that are commonly used as interior finishes in homes, to improve LCA results. Residential building …

Structural Behavior And Design Of Barrier-Overhang Connection In Concrete Bridge Superstructures Using Aashto Lrfd Method, Byungik Chang, Kamal Mirtalaei, Seungyeol Lee, Kenneth Leitch

Civil Engineering Faculty Publications

The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field. This investigation addresses the LRFD and Standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang. The purpose of this study is to propose a simplified manual design approach for the barrier-deck overhang in concrete bridges. For concrete deck slab overhang and barrier, application of National Cooperative Highway Research Program crash test is reviewed. The failure mechanism, design philosophy and load …

Optimization Of Post-Tensioned Box Girder Bridges With Special Reference To Use Of High-Strength Concrete Using Aashto Lrfd Method, Byungik Chang, Kamal Mirtalaei, Seungyeol Lee, Kenneth Leitch

Civil Engineering Faculty Publications

With the Federal Highway Administration-mandated implementation of the LRFD specifications, many state departments of transportation (DOTs) have already started implementing LRFD specifications as developed by the AASHTO. Many aspects of the LRFD specifications are being investigated by DOTs and researchers in order for seamless implementation for design and analysis purposes. This paper presents the investigation on several design aspects of post-tensioned box girder bridges designed by LRFD Specifications using conventional or High-Strength Concrete (HSC). A computer spreadsheet application was specifically developed for this investigation. It is capable of analysis, design, and cost evaluation of the superstructure for a cast-in-place post-tensioned …

Service Life Prediction Of Residential Interior Finishes For Life Cycle Assessment, Can B. Aktas Ph.D.

Civil Engineering Faculty Publications

Service life of building products has an important influence on life cycle assessment (LCA) results of buildings. The goal of this study was to propose a systematic approach to estimate service life of building products by including both technical and social factors. A hybrid service life prediction method, combining the statistical approach described in American Society for Testing and Materials (ASTM) standard G166, with the Factor Method adopted by International Organization for Standardization (ISO) standard 15686 was proposed. In their current forms, the two methods are not suitable to provide accurate lifetime estimates for the wide variety of products that …

Neutron Imaging And Applications: A Reference For The Imaging Community, Edmund Perfect, Chu-Lin Cheng, Peter Lehmann

Civil Engineering Faculty Publications

No abstract provided.

Application Of Noise Cancelling And Damage Detection Algorithms In Nde Of Concrete Bridge Decks Using Impact Signals, Gang Zhang, Ronald S. Harichandran, Pradeep Ramahulli

Civil Engineering Faculty Publications

Delamination is a commonly observed distress in concrete bridge decks. Among all the delamination detection methods, acoustic methods have the advantages of being fast and inexpensive. In traditional acoustic inspection methods, the inspector drags a chain alone or hammers on the bridge deck and detects delamination from the “hollowness” of the sound. The signals are often contaminated by ambient traffic noise and the detection of delamination is highly subjective. This paper describes the performance of an impact-based acoustic NDE method where the traffic noise was filtered by employing a noise cancelling algorithm and where subjectivity was eliminated by introducing feature …