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Full-Text Articles in Engineering

Propositions For A Resilient, Post-Covid-19 Future For The Aec Industry, Hala Nassereddine, Kyung Wook Seo, Zofia K. Rybkowski, Christian Schranz, Harald Urban Jul 2021

Propositions For A Resilient, Post-Covid-19 Future For The Aec Industry, Hala Nassereddine, Kyung Wook Seo, Zofia K. Rybkowski, Christian Schranz, Harald Urban

Civil Engineering Faculty Publications

The coronavirus outbreak has challenged and continues to challenge every aspect of the supply chain within the AEC industry, forcing stakeholders to cope with increasing uncertainties and continuous change. The notion of resilience is especially salient now. While the need for the AEC industry to focus on resilience has been highlighted in recent articles, there is a need for a comprehensive discussion on what resilience means for the AEC industry and how companies can create built-in resilience. This paper takes the form of a high-level overview of where the industry is headed and aims to establish eleven propositions for a …


Resilience Within And Resilience Without: Mindfulness And Sustainability Programming Using An Embedded Engineering Librarian Approach, Catherine Wong, Cynthia Carlson Jun 2020

Resilience Within And Resilience Without: Mindfulness And Sustainability Programming Using An Embedded Engineering Librarian Approach, Catherine Wong, Cynthia Carlson

Civil Engineering Faculty Publications

Students are facing an increasingly chaotic world in part due to global climate change and environmental degradation, causing rising levels of stress and anxiety. Mindfulness and sustainability programs were initiated over three years by a faculty-librarian collaborative team to assist first-year engineering students in building environmental literacy and personal resilience skills. The faculty-librarian team established in class and out of class themes, games, assignments, and programming using an embedded librarian approach. Sustainability programming included environmental movie nights with curricular links and conversations about climate change using the World Café methodology. These activities allowed students time outside of class to engage …


Thin-Walled Steel Tubular Circular Columns With Uniform And Graded Thickness Under Bidirectional Cyclic Loading, Qusay Al-Kaseasbeh, Iraj H.P. Mamaghani Dec 2019

Thin-Walled Steel Tubular Circular Columns With Uniform And Graded Thickness Under Bidirectional Cyclic Loading, Qusay Al-Kaseasbeh, Iraj H.P. Mamaghani

Civil Engineering Faculty Publications

Thin-walled steel tubular circular columns are becoming an increasingly attractive choice as cantilever bridge piers due to their architectural, structural and constructional advantages. This paper aims to evaluate the strength and ductility of thin-walled steel tubular circular columns with uniform thickness (BC) and graded thickness (BGC) under bidirectional cyclic lateral loading in the presence of constant axial force. The analysis is carried out using a finite-element model (FEM) which is substantiated based on the experimental results in the literature. Then, the proposed BGC column with size and volume of material equivalent to the BC column is investigated. As a part …


Evaluation Of Wind And Solar Energy Investments In Texas, Byungik Chang, Ken Starcher Mar 2019

Evaluation Of Wind And Solar Energy Investments In Texas, Byungik Chang, Ken Starcher

Civil Engineering Faculty Publications

The primary objective of the project is to evaluate the benefits of wind and solar energy and determine economical investment sites for wind and solar energy in Texas with economic parameters including payback periods. A 50 kW wind turbine system and a 42 kW PV system were used to collect field data. Data analysis enabled yearly energy production and payback period of the two systems.

The average payback period of a solar PV system was found to be within a range of 2-20 years because the large range of the payback period for PV systems were heavily influenced by incentives. …


Degradation Of 3-Nitro-1, 2, 4-Trizole-5-One (Nto) In Wastewater With Uv/H2o2 Oxidation, Amalia Terracciano, Christos Christodoulatos, Agamemnon Koutsospyros, Zhaoyu Zheng, Tsan-Liang Su, Benjamin Smolinski, Per Arienti, Xiaoguang Meng Dec 2018

Degradation Of 3-Nitro-1, 2, 4-Trizole-5-One (Nto) In Wastewater With Uv/H2o2 Oxidation, Amalia Terracciano, Christos Christodoulatos, Agamemnon Koutsospyros, Zhaoyu Zheng, Tsan-Liang Su, Benjamin Smolinski, Per Arienti, Xiaoguang Meng

Civil Engineering Faculty Publications

Insensitive Munition (IM) formulations contain 3-nitro-1,2,4-trizole-5-one (NTO), an energetic compound with the highest aqueous solubility (16 g L−1) among all IM explosives, including 2,4-dinitroanisole (DNAN) and 1-nitroguanidine (NQ); as a result wastewater streams from IM processing facilities can be highly contaminated and potentially toxic. The removal of energetic compounds from wastewater streams prior to their discharge in the environment is imperative, and new technology must be developed to efficiently treat high levels of NTO and other IM compounds in these streams. In this study, the treatment of NTO wastewater by a UV/H2O2 oxidation process under …


Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) Reduction By Granular Zero-Valent Iron In Continuous Flow Reactor, Amalia Terracciano, Jie Ge, Agamemnon Koutsospyros, Xiaoguang Meng, Benjamin Smolinski, Per Arienti Oct 2018

Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) Reduction By Granular Zero-Valent Iron In Continuous Flow Reactor, Amalia Terracciano, Jie Ge, Agamemnon Koutsospyros, Xiaoguang Meng, Benjamin Smolinski, Per Arienti

Civil Engineering Faculty Publications

Wastewater streams containing hexahydro-1, 3, 5-trinitro-1, 3, 5-triazine (RDX) are subject to regulatory discharge regulations that require processing through industrial waste treatment. Thus, the development of easy-to-apply technologies for the treatment of RDX-laden wastewater streams is imperative. In the present study, the reduction of RDX by granular zero valent iron (GZVI) in batch and column experiments was investigated. Preliminary batch tests conducted under both oxic and anoxic conditions showed that after 3.0 hours of reaction with GZVI, RDX was mainly converted to formaldehyde (CH2O), nitrate (NO3 - ), and ammonium (NH4 + ). Column filtration tests …


Characterization Of Mg-Based Bimetal Treatment Of Insensitive Munition 2,4-Dinitroanisole, Emese Hadnagy, Andrew Mai, Benjamin Smolinski, Washington Braida, Agamemnon Koutsospyros Jun 2018

Characterization Of Mg-Based Bimetal Treatment Of Insensitive Munition 2,4-Dinitroanisole, Emese Hadnagy, Andrew Mai, Benjamin Smolinski, Washington Braida, Agamemnon Koutsospyros

Civil Engineering Faculty Publications

The manufacturing of insensitive munition 2,4-dinitroanisole (DNAN) generates waste streams that require treatment. DNAN has been treated previously with zero-valent iron (ZVI) and Fe-based bimetals. Use of Mg-based bimetals offers certain advantages including potential higher reactivity and relative insensitivity to pH conditions. This work reports preliminary findings of DNAN degradation by three Mg-based bimetals: Mg/Cu, Mg/Ni, and Mg/Zn. Treatment of DNAN by all three bimetals is highly effective in aqueous solutions (> 89% removal) and wastewater (> 91% removal) in comparison with treatment solely with zero-valent magnesium (ZVMg; 35% removal). Investigation of reaction byproducts supports a partial degradation pathway involving …


Bio-Inspired Hybrid Vibration Control Methodology For Intelligent Isolated Bridge Structures, Mariantonieta Gutierrez Soto Mar 2018

Bio-Inspired Hybrid Vibration Control Methodology For Intelligent Isolated Bridge Structures, Mariantonieta Gutierrez Soto

Civil Engineering Faculty Publications

Inspired by evolutionary game theory, the biological game of replicator dynamics is investigated for vibration control of bridge structures subjected to earthquake excitations. Replicator dynamics can be interpreted economically as a model of imitation of successful individuals. This paper uses replicator dynamics to reduce vibrations while optimally allocating the control device forces. The control algorithm proposed is integrated with a patented neural dynamic optimization algorithm to find optimal growth rate values with the goal of achieving satisfactory structural performance with minimum energy consumption. A model is described for hybrid vibration control of smart highway bridge structures subjected to earthquake loading.


Stabilization Of Lead (Pb) And Zinc (Zn) In Contaminated Rice Paddy Soil Using Starfish: A Preliminary Study, Deok Hyun Moon, Inseong Hwang, Agamemnon Koutsospyros, Kyung Hoon Cheong, Yong Sik Ok, Won Hyun Ji, Jeong Hun Park Feb 2018

Stabilization Of Lead (Pb) And Zinc (Zn) In Contaminated Rice Paddy Soil Using Starfish: A Preliminary Study, Deok Hyun Moon, Inseong Hwang, Agamemnon Koutsospyros, Kyung Hoon Cheong, Yong Sik Ok, Won Hyun Ji, Jeong Hun Park

Civil Engineering Faculty Publications

Lead (Pb) and zinc (Zn) contaminated rice paddy soil was stabilized using natural (NSF) and calcined starfish (CSF). Contaminated soil was treated with NSF in the range of 0-10 wt.% and CSF in the range of 0-5 wt.% and cured for 28 days. Toxicity characteristic leaching procedure (TCLP) test was used to evaluate effectiveness of starfish treatment. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) analyses were conducted to investigate the mechanism responsible for effective immobilization of Pb and Zn. Experimental results suggest that NSF and CSF treatments effectively immobilize Pb and Zn in treated rice paddy soil. TCLP levels for …


Performance Study On Evacuated Tubular Collector Coupled Solar Still In West Texas Climate, Roy Issa, Byungik Chang Jul 2017

Performance Study On Evacuated Tubular Collector Coupled Solar Still In West Texas Climate, Roy Issa, Byungik Chang

Civil Engineering Faculty Publications

Experimental study was performed on a single basin active solar distillation system augmented with a solar collector using evacuated solar tubes. Field tests were conducted over several days under the climatic conditions of West Texas to evaluate the effect evacuated solar tubes have on the daily distillate yield rate. To investigate the feasibility of the solar tubes, active and passive solar stills with and without exterior insulation were examined. The maximum daily production rate for the active distillation system using evacuated solar tubes and the passive distillation system was 3.6 and 1.4 kg/m2day, respectively. The results showed the …


Vulnerability Of Coastal Connecticut To Sea Level Rise: Land Inundation And Impacts To Residential Property, Rebecca Andreucci, Can B. Aktas May 2017

Vulnerability Of Coastal Connecticut To Sea Level Rise: Land Inundation And Impacts To Residential Property, Rebecca Andreucci, Can B. Aktas

Civil Engineering Faculty Publications

Vulnerability indices at the global or national scales require considerable data aggregation where local economic and social impacts remain unnoticed. The goal of this study was to analyze the extent of inundated land from sea level rise and its economic impacts to residential property in coastal communities. Geographic data were integrated with economic and social data at parcel level resolution through GIS. Cumulative land inundation in seven coastal municipalities was calculated as 15 and 25 km2, while direct economic costs to residential property was estimated to be $1.3 billion and $2.2 billion for 1 and 2 m sea …


Application Of Gis To Prioritize Brownfield Sites For Green Building Construction Based On Leed Criteria, Can B. Aktas, Paul Bartholomew, Sabrina Church Mar 2017

Application Of Gis To Prioritize Brownfield Sites For Green Building Construction Based On Leed Criteria, Can B. Aktas, Paul Bartholomew, Sabrina Church

Civil Engineering Faculty Publications

Although there are many initiatives to create incentives for investors and developers to invest in and redevelop brownfield sites, efficient prioritization of brownfields by taking into account environmental, economic, and social constraints remains a challenge. This study introduces a method to screen numerous brownfields over large geographic areas by using geographic information systems (GIS) and to assess and prioritize such sites for green building suitability based on leadership in energy and environmental design (LEED) criteria. A case study was completed for the greater Bridgeport, Connecticut region. With 279 brownfield sites, the city has among the highest number of brownfields in …


Life Cycle Environmental And Economic Performance Of Biochar Compared With Activated Carbon: A Meta-Analysis, Hashim A. Alhashimi, Can B. Aktas Mar 2017

Life Cycle Environmental And Economic Performance Of Biochar Compared With Activated Carbon: A Meta-Analysis, Hashim A. Alhashimi, Can B. Aktas

Civil Engineering Faculty Publications

As the commercial production and distribution of biochar continues to grow internationally, and its applications diversifying from its early uses as soil amendment, it is important to study the environmental impacts and economic performance of biochar in comparison to activated carbon in order to assess its value. The goal of the study was to assess, through a meta-analysis, the environmental and economic performance of biochar in comparison to activated carbon under an equivalent functional unit to adsorb heavy metals. More than 80 data points on adsorption capacity of biochar and activated carbon were identified through literature, which were statistically analyzed …


Quality Improvement Of Acidic Soils By Biochar Derived From Renewable Materials, Deok Hyun Moon, Inseong Hwang, Yoon-Young Chang, Agamemnon Koutsospyros, Kyung Hoon Cheong, Won Hyun Ji, Jeong Hun Park Feb 2017

Quality Improvement Of Acidic Soils By Biochar Derived From Renewable Materials, Deok Hyun Moon, Inseong Hwang, Yoon-Young Chang, Agamemnon Koutsospyros, Kyung Hoon Cheong, Won Hyun Ji, Jeong Hun Park

Civil Engineering Faculty Publications

Biochar derived from waste plant materials and agricultural residues was used to improve the quality of an acidic soil. The acidic soil was treated for 1 month with both soy bean stover-derived biochar and oak-derived biochar in the range of 1 to 5 wt% for pH improvement and exchangeable cation enhancement. Following 1 month of treatment, the soil pH was monitored and exchangeable cations were measured. Moreover, a maize growth experiment was performed for 14 days with selected treated soil samples to confirm the effectiveness of the treatment. The results showed that the pH of the treated acidic soil increased …


System-Dynamics Modeling Of Source Mass-Depletion And Risk-Exposure Evolution For Natural Attenuation Processes In The Vadose Zone, Aspasia Kalomoiri, Agamemnon Koutsospyros, Washington Braida, Julius Pavlov Jan 2017

System-Dynamics Modeling Of Source Mass-Depletion And Risk-Exposure Evolution For Natural Attenuation Processes In The Vadose Zone, Aspasia Kalomoiri, Agamemnon Koutsospyros, Washington Braida, Julius Pavlov

Civil Engineering Faculty Publications

Public health is potentially at risk after a contaminant of concern (COC) is released into the ecosphere. The extent of contamination depends on numerous factors; modeling a contaminant’s dynamic behavior is challenging, given the multitude of relevant parameters and the fluid nature of processes involved. For example, weather events (e.g., wet or dry periods) may affect the mass depletion and the fate and transport of COCs, and hence, the risk assessment of current and potential future exposures. Thus, to give realistic estimates for potential risks, a contaminant’s dynamic behavior must be taken into account in decision-making processes. In this paper, …


Freeze-Thaw Durability Of Concrete Columns Wrapped With Frp And Subject To Corrosion-Like Expansion, Ronald S. Harichandran, M.I. Baiyasi, G. Nossoni Jan 2017

Freeze-Thaw Durability Of Concrete Columns Wrapped With Frp And Subject To Corrosion-Like Expansion, Ronald S. Harichandran, M.I. Baiyasi, G. Nossoni

Civil Engineering Faculty Publications

Experiments were conducted to assess the effects of using fiber-reinforced polymer (FRP) wraps, with fibers oriented in the hoop direction, for rehabilitating corrosion-damaged columns. This paper reports findings related to the freeze-thaw durability of concrete specimens with round and square cross sections, wrapped with glass and carbon FRP, after they are subjected to an internal expansive force similar to that generated by corroding steel. The results of the experiment indicate that freeze-thaw cycles have no statistically significant effect on the compressive strength of glass- and carbon-wrapped specimens. Freeze-thaw conditioning generally reduced the longitudinal failure strain of wrapped specimens. The square …


Economic Feasibility Of Campus-Wide Photovoltaic Systems In New England, Jongsung Lee, Byungik Chang, Can B. Aktas, Ravi Gorthala Dec 2016

Economic Feasibility Of Campus-Wide Photovoltaic Systems In New England, Jongsung Lee, Byungik Chang, Can B. Aktas, Ravi Gorthala

Civil Engineering Faculty Publications

Compared to the national average residential retail electricity price, Connecticut (CT) had the 4th 26 highest electricity price in the country with 19.23 cents/kWh in September 2015, nearly 50% 27 higher than the national average for price of electricity. This study aims to assess the economic 28 feasibility of the solar PV systems at the campus under realistic constraints, by analyzing actual 29 data from the solar array on campus. The project focused on the economic feasibility of solar PV 30 systems on campus with physical, spatial, and practical constraints that result in a project to 31 deviate from theoretical …


Sustainable Temporary Housing: Global Trends And Outlook, Daniel V. Perrucci, Bianca A. Vazquez, Can B. Aktas Dec 2016

Sustainable Temporary Housing: Global Trends And Outlook, Daniel V. Perrucci, Bianca A. Vazquez, Can B. Aktas

Civil Engineering Faculty Publications

The concept of sustainable housing can take many forms or definitions. The view embraced in this study for sustainable housing was a structure that is low-cost, energy efficient, and one that uses local renewable or recycled materials, while at the same time being safe and providing shelter to its occupants from the elements. Rather than focus on a few aspects of housing in isolation from spatial necessities or occupant demographics, the approach used in this study was to seek best practices for sustainable temporary housing that also accounts for local climatic conditions. The global need for temporary housing may be …


Characteristics And Products Of The Reductive Degradation Of 3-Nitro-1,2,4-Triazol-5-One (Nto) And 2,4-Dinitroanisole (Dnan) In A Fe-Cu Bimetal System, Elsie Kitcher, Washington Braida, Agamemnon Koutsospyros, Julius Pavlov, Tsang-Liang Su Nov 2016

Characteristics And Products Of The Reductive Degradation Of 3-Nitro-1,2,4-Triazol-5-One (Nto) And 2,4-Dinitroanisole (Dnan) In A Fe-Cu Bimetal System, Elsie Kitcher, Washington Braida, Agamemnon Koutsospyros, Julius Pavlov, Tsang-Liang Su

Civil Engineering Faculty Publications

It has been shown previously that, under acidic conditions, 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4-dinitroanisole (DNAN) degrade in the presence of iron/copper bimetal particles; the reactions can be modeled by pseudo-first-order kinetics. This study investigates the reaction mechanisms of the degradation processes under different conditions. Batch studies were conducted using laboratory-prepared solutions and an industrial insensitive munition-laden (IMX) wastewater. The influence of parameters such as initial pH of the solution, copper/iron (Fe-Cu) contact, and solid/liquid ratio were systematically investigated to assess their impact on the reaction kinetics. These parameters were subsequently incorporated into pseudo-first-order decomposition models for NTO and DNAN. The activation …


Development Of An Instrument To Measure The Entrepreneurial Mindset Of Engineering Students, Cheryl Q. Li, Ronald S. Harichandran, Maria-Isabel Carnasciali, Nadiye O. Erdil, Jean Nocito-Gobel Jun 2016

Development Of An Instrument To Measure The Entrepreneurial Mindset Of Engineering Students, Cheryl Q. Li, Ronald S. Harichandran, Maria-Isabel Carnasciali, Nadiye O. Erdil, Jean Nocito-Gobel

Civil Engineering Faculty Publications

This work in progress describes the development of an instrument to measure entrepreneurial mindset of engineering students. The need for developing the entrepreneurial mindset of engineering students is being recognized by many universities. However, very few comprehensive, generalized and well-validated instruments are available for assessing the entrepreneurial mindset of engineering students. Most research and educational efforts focus on the design and implementation of engineering entrepreneurship programs, but assessment practices have not kept up.1-2 There are several reasons for the shortfall in assessment practices: 1) Introducing engineering students to entrepreneurship is a relatively new trend and it will take time for …


Assessment Of Soil Washing For Simultaneous Removal Of Heavy Metals And Low-Level Petroleum Hydrocarbons Using Various Washing Solutions, Deok-Hyun Moon, Jae-Woo Park, Agamemnon Koutsospyros, Kyung Hoon Cheong, Yoon-Young Chang, Ki-Tae Baek, Raehyun Jo, Jeong-Hun Park May 2016

Assessment Of Soil Washing For Simultaneous Removal Of Heavy Metals And Low-Level Petroleum Hydrocarbons Using Various Washing Solutions, Deok-Hyun Moon, Jae-Woo Park, Agamemnon Koutsospyros, Kyung Hoon Cheong, Yoon-Young Chang, Ki-Tae Baek, Raehyun Jo, Jeong-Hun Park

Civil Engineering Faculty Publications

Bench-scale soil washing experiments were conducted for simultaneous removal of heavy metals (Pb, Cu, Zn) and low-level petroleum hydrocarbon contaminants from soils. Various washing solutions including hydrochloric acid (HCl), nitric acid (HNO3), sulfuric acid (H2SO4), tartaric acid (C4H6O6) and ethylenediaminetetraacetic acid (C10H16N2O8, EDTA) were used. The concentration of the washing solutions ranged from 0.1 to 3M with a liquid-to-solid ratio of 10. The soil washing results showed that hydrochloric acid (HCl) was the best washing solution at 3M for heavy …


Resilience Of Rail Infrastructure In The U.S. Northeast Corridor, Daniel Delgado, Can B. Aktas Ph.D. Jan 2016

Resilience Of Rail Infrastructure In The U.S. Northeast Corridor, Daniel Delgado, Can B. Aktas Ph.D.

Civil Engineering Faculty Publications

The New Haven Line reports a record number of passengers every year as it continues to experience a steady increase in ridership. In 2012, the railroad reported 39 million passengers, with a further increase of 46% predicted over the next 18 years eventually reaching 57 million trips annually by 2030. Despite the great importance of the rail infrastructure for the region, problems exist for operating under harsh weather-related conditions, and when congestion or frequent malfunctions disrupts system timeliness with speed restrictions. These on-time performance and reliability issues have significant economic, environmental, and societal impacts. The aim of this study was …


Analysis Of Credits Earned By Leed Healthcare Certified Facilities, Maryam Golbazi, Can B. Aktas Jan 2016

Analysis Of Credits Earned By Leed Healthcare Certified Facilities, Maryam Golbazi, Can B. Aktas

Civil Engineering Faculty Publications

One of the main aims of the green building movement has been a desire to create a healthy indoor environment for building occupants. In terms of improving or enhancing occupant well-being, a unique case emerges for healthcare facilities, whose main existence is based on the principles of improving the health of their patients. In the U.S., the Leadership in Energy and Environmental Design (LEED) rating system has become the most widely recognized and used certification system for green buildings, including green hospital buildings. However, hospitals with high total scores may be green buildings but not necessarily the optimal green healthcare …


Assessing The Resilience Of Leed Certified Green Buildings, Cassandra Champagne, Can B. Aktas Jan 2016

Assessing The Resilience Of Leed Certified Green Buildings, Cassandra Champagne, Can B. Aktas

Civil Engineering Faculty Publications

The Leadership in Energy & Environmental Design (LEED) green building certification program is dedicated to the design of sustainable buildings by incentivizing reductions in energy, water, and building materials consumption, while at the same time enhancing occupant health and overall community connectivity. While green buildings certified by the program do reduce the environmental footprint of buildings, they must also be designed for resilience to withstand external stressors that may arise over the buildings’ lifetime for it to be truly sustainable. Therefore, a resilient building should be able to adapt and remain functional while under pressure from more frequent and severe …


Prospects For Meeting The Corporate Average Fuel Economy Standards In The U.S., Jessica Zielinski, Rebecca Andreucci, Can B. Aktas Jan 2016

Prospects For Meeting The Corporate Average Fuel Economy Standards In The U.S., Jessica Zielinski, Rebecca Andreucci, Can B. Aktas

Civil Engineering Faculty Publications

In 2013, the transportation sector accounted for 34% of the United States’ greenhouse gas emissions, with no significant change from prior years. Efforts to improve vehicle transportation efficiency and curb associated environmental emissions had led to the Corporate Average Fuel Economy (CAFE) standards for passenger cars and light trucks initially introduced in 1975. The National Highway Traffic Safety Administration has phased in new standards recently that require an average combined fleetwide fuel economy of 35.1 - 35.4 mpg by 2017, 40.3 - 41.0 mpg by 2021, and 48.7 - 49.7 mpg by 2025. The new legislation has the potential to …


The Importance Of The “Local” In Walkability, Cynthia Carlson, Semra Aytur, Kevin Gardner, Shannon Rogers Oct 2015

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 …


Interfacial Bond Between Reinforcing Fibers And Calcium Sulfoaluminate Cements: Fiber Pullout Characteristics, Robert B. Jewell, Kamyar C. Mahboub, Thomas L. Robl, Arne C. Bathke Jan 2015

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 …


Soil Washing Of Fluorine Contaminated Soil Using Various Washing Solutions, Deok-Hyun Moon, Rae-Hyun Jo, Agamemnon Koutsospyros, Kyung Hoon Cheong, Jeong-Hun Park Jan 2015

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 Jan 2015

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 Jan 2015

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, …