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Full-Text Articles in Civil and Environmental Engineering

Raising The Green Roof: Enhancing Youth Water Literacy Through Built Environment Education, Laura B. Cole, Lilian Priscilla, Laura Zangori, Beth Kania-Gosche, Joel G. Burken May 2024

Raising The Green Roof: Enhancing Youth Water Literacy Through Built Environment Education, Laura B. Cole, Lilian Priscilla, Laura Zangori, Beth Kania-Gosche, Joel G. Burken

Teacher Education and Certification Faculty Research & Creative Works

Green Roofs Cool Cities, Clean the Air, Provide Habitat, and Manage Stormwater. They Are Compelling Tools to Teach Interconnected Human-Ecological Systems. This Study Included the Design, Pilot, and Evaluation of a Fourth-Grade Science Unit Entitled "Raising the Green Roof", Exploring These Connections. Five Classrooms in Two Midwestern U.S. Public Elementary Schools Participated, and 4th-Grade Students (N = 73) Drew Systems Models at Three Time Points (212 Models) and Wrote their Ideas. Qualitative Content Analyses of the Models Showed that Learners Were Increasingly Combining Social Systems (Green Roof Infrastructure) with Ecological Systems (Water Cycle) Across the Unit. Students Also Increasingly Evidenced …


Four-Way Cfd-Dem Coupling To Simulate Concrete Pipe Flow: Mechanism Of Formation Of Lubrication Layer, Tooran Tavangar, Masoud Hosseinpoor, Jeffrey S. Marshall, Ammar Yahia, Kamal H. Khayat May 2024

Four-Way Cfd-Dem Coupling To Simulate Concrete Pipe Flow: Mechanism Of Formation Of Lubrication Layer, Tooran Tavangar, Masoud Hosseinpoor, Jeffrey S. Marshall, Ammar Yahia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study introduced a four-way CFD-DEM coupling approach to simulate the shear-induced particle migration (SIPM) mechanism leading to formation of the lubrication layer (LL) during concrete pumping. The CFD-DEM simulations considered the coupled effect of concentration (10 %–40 %) and wide size distribution (1–17 mm) of aggregate and rheology of the mortar for forces between the suspending matrix and the particles (and vice versa), as well as force transmission directly between particles (and the pipe wall). The formation of the LL was successfully simulated through a more realistic understanding the SIPM mechanism and rheological evaluation across the pipe with comparable …


Comparison Of Embodied Carbon Footprint Of A Mass Timber Building Structure With A Steel Equivalent, Mahboobeh Hemmati, Tahar Messadi, Hongmei Gu, Jacob Seddelmeyer, Moein Hemmati May 2024

Comparison Of Embodied Carbon Footprint Of A Mass Timber Building Structure With A Steel Equivalent, Mahboobeh Hemmati, Tahar Messadi, Hongmei Gu, Jacob Seddelmeyer, Moein Hemmati

Architecture Faculty Publications and Presentations

The main purpose of this study is to quantify and compare the embodied carbon (EC) from the materials used or designed to build the Adohi Hall, a residence building located on the University of Arkansas campus in Fayetteville, AR. It has been constructed as a mass timber structure. It is compared to the same building design with a steel frame for this study. Based on the defined goal and scope of the project, all materials used in the building structure are compared for their global warming potential (GWP) impact by applying a life cycle assessment (LCA) using a cradle-to-construction site …


Equitable Infrastructure: Achieving Resilient Systems And Restorative Justice Through Policy And Research Innovation, Jason P. Giovannettone, Gregg P. Macey, Amir Aghakouchak, Michele Barbato, William J. Capehart, Auroop R. Ganguly, Mital Hall, Jennifer F. Helgeson, Si Han Li, Teng Wu, Guirong Yan, Farshid Vahedifard May 2024

Equitable Infrastructure: Achieving Resilient Systems And Restorative Justice Through Policy And Research Innovation, Jason P. Giovannettone, Gregg P. Macey, Amir Aghakouchak, Michele Barbato, William J. Capehart, Auroop R. Ganguly, Mital Hall, Jennifer F. Helgeson, Si Han Li, Teng Wu, Guirong Yan, Farshid Vahedifard

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Recent major investments in infrastructure in the United States and globally present a crucial opportunity to embed equity within the heart of resilient infrastructure decision-making. Yet there is a notable absence of frameworks within the engineering and scientific fields for integrating equity into planning, design, and maintenance of infrastructure. Additionally, whole-of-government approaches to infrastructure, including the Justice40 Initiative, mimic elements of process management that support exploitative rather than exploratory innovation. These and other policies risk creating innovation traps that limit analytical and engineering advances necessary to prioritize equity in decision-making, identification and disruption of mechanisms that cause or contribute to …


Investigating Causes Of Disputes Resulting In Litigation In Airport Development Projects In The United States Using Graph-Based Techniques, Ramy Khalef, Islam H. El-Adaway May 2024

Investigating Causes Of Disputes Resulting In Litigation In Airport Development Projects In The United States Using Graph-Based Techniques, Ramy Khalef, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Airports represent a crucial a sector of the US infrastructure, but they were documented to have scored a D+. To mitigate this, governmental authorities have issued initiatives to update the airport infrastructure. With an expected critical junction for a major transformation in the airport sector, it is anticipated that airport projects will increase. This shall result in an escalation in the number of disputes. Previous research analyzed dispute concerns within the construction sector, but none tackled the perspective of airport projects. Accordingly, the goal of this study is to investigate the leading causes of disputes in litigation within US airport …


Micro-Mechanical Characterization Of Uhpc Stiffness Mechanisms: Towards A Better Understanding Of Concrete Elastic Modulus, Charissa N. Puttbach May 2024

Micro-Mechanical Characterization Of Uhpc Stiffness Mechanisms: Towards A Better Understanding Of Concrete Elastic Modulus, Charissa N. Puttbach

Graduate Theses and Dissertations

Current design code equations for estimating the elastic modulus of specialty concretes like ultra-high performance concrete are not all suitable. Developing empirical curves from exhaustive experimental testing is challenging for concretes that may have high levels of cement replacement with mineral admixtures and fibers at varying volume contents. As such, an alternative approach is taken that seeks to understand the constituent microscale stiffness mechanisms and relate the results to the macroscale. Micropillars are fabricated on several cement paste phases using a focused ion beam. A modified pico-indenter is used to determine the linear and non-linear behavior under micro-compression loading. Micropillar …


Providing A Statistical Analysis Framework For Agencies To Analyze The Parameters Influencing The Rutting And Cracking Performance Of Asphalt Mixtures, Mohammad Tahir Ansari May 2024

Providing A Statistical Analysis Framework For Agencies To Analyze The Parameters Influencing The Rutting And Cracking Performance Of Asphalt Mixtures, Mohammad Tahir Ansari

Graduate Theses and Dissertations

Many state agencies recognize that their current asphalt mixtures are susceptible to cracking and poor durability. Some agencies are adjusting their mix design procedures to increase the asphalt binder content, while others are moving toward a balanced mix design (BMD) to try and address both cracking and rutting. However, there is uncertainty on what asphalt mixture properties can impact cracking and rutting. This research explores the IDEAL-CT and APA data from two years of mix designs collected by ARDOT. To understand which asphalt mixture properties impact cracking and rutting in the field, Pearson correlation (PCM), Spearman rank correlation (SCM) and …


Proctor And Harvard Miniature Compaction Energy Comparison, Julia Loshelder May 2024

Proctor And Harvard Miniature Compaction Energy Comparison, Julia Loshelder

Graduate Theses and Dissertations

Compaction with the Harvard Miniature Compaction Apparatus (HMCA) was investigated to develop a method that can be used in place of typical Proctor compaction. Advantages for compaction with the HMCA include the need for less soil for testing and less preparation time. To investigate the potential for HMCA as a replacement, soil specimens were compacted with both the Proctor and HMCA methodologies at equivalent energies. For this testing, the testing included modified energy (56,250 ft-lbf/ft3 [2693 kN-m/m3]), standard energy (12,375 ft-lbf/ft3 [593 kN-m/m3]), and reduced energy (6188 ft-lbf/ft3 [296 kN-m/m3]). Because …


Addressing Data Limitations Of Commercial Waterways Via Machine Learning And Stochastic Optimization, Sanjeev Bhurtyal May 2024

Addressing Data Limitations Of Commercial Waterways Via Machine Learning And Stochastic Optimization, Sanjeev Bhurtyal

Graduate Theses and Dissertations

Freight transportation is a crucial component of the US economy, with truck, rail, and water contributing significantly to the Gross Domestic Product (GDP). However, challenges arise in maintaining infrastructure capacity to accommodate the growing tonnage and value of freight transportation. Waterways offer high efficiency and environmental friendliness, with the capacity to transport substantial cargo volumes. Utilizing waterways can alleviate bottlenecks in landside transportation, accommodating the rising tonnage of commodity flow in the US. Despite the advantages of waterway transportation, the data limitations hinder informed decision-making regarding port operation and infrastructure investment. The lack of granularity and timeliness in available data …


Cyclic Testing Of A Skewed Special Moment Frame Rbs Connection Having A Composite Concrete Slab, Adam Neil Kirchner May 2024

Cyclic Testing Of A Skewed Special Moment Frame Rbs Connection Having A Composite Concrete Slab, Adam Neil Kirchner

Graduate Theses and Dissertations

Special moment frames (SMFs) having reduced beam section (RBS) connections are commonly used in high seismic areas as they resist lateral forces while preserving critical welded connection regions. RBS SMFs provide brace-free, unobstructed frame options which can be favorable for architectural purposes. However, when building designs require non-rectangular framing, laterally skewed connections may be needed. Current design provisions for SMF connections provide only limited commentary on such non-orthogonal connections as limited research exists documenting skewed frame behavior. This study experimentally evaluates the cyclic behavior of a full-scale double-sided skewed SMF RBS specimen having a composite concrete slab. During the imposed …


Use Of Bcsa Cement In Soil-Cement Mixtures As A Rapid Flood Repair Technique, Mariel Mayori Rivero May 2024

Use Of Bcsa Cement In Soil-Cement Mixtures As A Rapid Flood Repair Technique, Mariel Mayori Rivero

Graduate Theses and Dissertations

The research discusses the vulnerable condition of hydraulic structures, specially dams and levees located in the United States, structures that are often times made of earthfill material and that have been greatly impacted by recent flood events. The need for a rapid setting material for active flood fighting efforts is inarguable, in order to mitigate collateral expenses caused by the often long closure times when repair is taking place, especially when dewatering is necessary. Therefore, this research tested different proportions of cement in soil-cement mixtures at varying moisture contents with the interest of evaluating the performance of the soil-cement when …


Review: Implementation Of Video Documentation In Lessons Learned System In Construction, Jainil Patel May 2024

Review: Implementation Of Video Documentation In Lessons Learned System In Construction, Jainil Patel

2024 Spring Honors Capstone Projects - Archive

Organizations employ Lessons Learned Systems (LLS) to manage knowledge and capture valuable project experiences to improve future performance. However, the construction industry has yet to adopt such systems widely, presumably due to its sluggish tech integration and risk-prone characteristics. Of the numerous fragmented obstacles that impede LLS adoption, one noteworthy obstacle would be the challenge faced during the text documentation of experiences. Traditional text inputs are labor-intensive and time- consuming. Hence, video documentation can be a more efficient replacement with its quick and modern recording features. The technological advancement and the preference shift of younger generations from text to video …


Investigating Rural Traffic Dynamics: A Traffic Study On E 2nd Street Intersection’S Behavior And Safety, Ma Anjelika Rose T. Pineda May 2024

Investigating Rural Traffic Dynamics: A Traffic Study On E 2nd Street Intersection’S Behavior And Safety, Ma Anjelika Rose T. Pineda

2024 Spring Honors Capstone Projects - Archive

Traffic studies guide engineers in designing road networks to ensure smooth traffic flow and public safety. Such studies assess the need for traffic control devices to manage vehicle flow safely and efficiently. This is crucial at intersections which pose high risks of collision and congestion. A traffic analysis at the intersection of Island Grove and E 2nd Street on the FM-4 roadway in Cleburne, TX was conducted to evaluate the sufficiency of the current traffic control device. TxDOT warrants and standards and a field study were utilized and performed to justify the substitution for a traffic signal at the intersection. …


An Assessment Of Methane Cracking Technologies For Hydrogen Production And Reduction Of Greenhouse Gases, Alisa E. Pjetrovic May 2024

An Assessment Of Methane Cracking Technologies For Hydrogen Production And Reduction Of Greenhouse Gases, Alisa E. Pjetrovic

2024 Spring Honors Capstone Projects - Archive

Methane reformation and methane pyrolysis involve separating, or cracking, the components of methane, leading to the production of hydrogen gas, and in the case of pyrolysis, solid carbon. Because methane is known as a leading cause of climate change, these technologies are gaining attention as the global community moves to address methane as a greenhouse gas. This study aims to assess, through a systematic literature review, the current state-of-the-art methane cracking technologies based on seven technology criteria: hydrogen production capability, environmental impact, value of carbon produced, reaction stability, operating temperature requirements, energy requirements, and Technology Readiness Level (TRL). This study …


Emergency Vehicle Prioritization In Connected And Autonomous Traffic., Mohamadreza Haghani May 2024

Emergency Vehicle Prioritization In Connected And Autonomous Traffic., Mohamadreza Haghani

Electronic Theses and Dissertations

Reducing the response time of emergency vehicles (EV) is highly important due to the relationship between response time and fatality rate. Emerging technologies can help reduce response time by enhancing EV prioritization. On the other hand, EV prioritization can negatively impact general traffic especially in cross streets of signalized intersections. In this research, three main objectives were followed. Firstly, creation and dissipation of EVP disruption on arterial cross streets was studied to recommend solutions to prevent this disruption. Secondly, lane-changing and stopping behavior of CAVs were studied in EV prioritization to identify the best lane-changing behavior through minimizing delay. Thirdly, …


Effect Of Swirl Ratio On Simulated Vortech Chamber Vortex Parameters, Samuel Kolar May 2024

Effect Of Swirl Ratio On Simulated Vortech Chamber Vortex Parameters, Samuel Kolar

Civil Engineering Undergraduate Honors Theses

A numerical simulator can use computational fluid dynamics (CFD) to model an experimental tornado-simulating chamber at Texas Tech University (known as VorTECH). Previous studies evaluating this particular CFD model have produced results that compare the touchdown swirl ratio (STD), core radius (rc), maximum tangential velocity at touchdown (Vtmax @ STD), and height of the maximum tangential velocity (zc) reasonably well with experimental data from the VorTECH facility. The effects of swirl ratio beyond STD on important vortex parameters including rc, Vtmax, z …


The Development Of A Convenient And Consistent Methodology For Flight Proficiency To Certify Multi-Rotor Uas Pilots For State Departments Of Transportation, Colin Dees May 2024

The Development Of A Convenient And Consistent Methodology For Flight Proficiency To Certify Multi-Rotor Uas Pilots For State Departments Of Transportation, Colin Dees

All Dissertations

To fly an unmanned aircraft system (UAS), commonly referred to as a “drone,” the Federal Aviation Administration (FAA) requires pilots to pass a knowledge test. There is no requirement at the state or federal level for drone operators to demonstrate the ability to operate a UAS. The National Institute of Science and Technology (NIST) has created an exam for public and private entities to assess basic UAS flight proficiency. It is the only nationally recognized flight proficiency protocol. NIST does not provide a scoring recommendation and leaves it to the user to determine the minimum criteria to pass. There is …


An Adaptive Large Neighborhood Search For The Multi-Vehicle Profitable Tour Problem With Flexible Compartments And Mandatory Customers, Vincent F. Yu, Nabila Yuraisyah Salsabila, Aldy Gunawan, Anggun Nurfitriani Handoko May 2024

An Adaptive Large Neighborhood Search For The Multi-Vehicle Profitable Tour Problem With Flexible Compartments And Mandatory Customers, Vincent F. Yu, Nabila Yuraisyah Salsabila, Aldy Gunawan, Anggun Nurfitriani Handoko

Civil and Environmental Engineering Faculty Publications and Presentations

The home-refill delivery system is a business model that addresses the concerns of plastic waste and its impact on the environment. It allows customers to pick up their household goods at their doorsteps and refill them into their own containers. However, the difficulty in accessing customers’ locations and product consolidations are undeniable challenges. To overcome these issues, we introduce a new variant of the Profitable Tour Problem, named the multi-vehicle profitable tour problem with flexible compartments and mandatory customers (MVPTPFC-MC). The objective is to maximize the difference between the total collected profit and the traveling cost. We model the proposed …


To What Extent Do Water Reuse Treatments Reduce Antibiotic Resistance Indicators? A Comparison Of Two Full-Scale Systems, Ishi Keenum, Jeanette Calarco, Haniyyah Majeed, E. Eldridge Hager-Soto, Charles Bott, Emily Garner, Valerie J. Harwood, Amy Pruden May 2024

To What Extent Do Water Reuse Treatments Reduce Antibiotic Resistance Indicators? A Comparison Of Two Full-Scale Systems, Ishi Keenum, Jeanette Calarco, Haniyyah Majeed, E. Eldridge Hager-Soto, Charles Bott, Emily Garner, Valerie J. Harwood, Amy Pruden

Michigan Tech Publications

Water reuse is an essential strategy for reducing water demand from conventional sources, alleviating water stress, and promoting sustainability, but understanding the effectiveness of associated treatment processes as barriers to the spread of antibiotic resistance is an important consideration to protecting human health. We comprehensively evaluated the reduction of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) in two field-operational water reuse systems with distinct treatment trains, one producing water for indirect potable reuse (ozone/biologically-active carbon/granular activated carbon) and the other for non-potable reuse (denitrification-filtration/chlorination) using metagenomic sequencing and culture. Relative abundances of total ARGs/clinically-relevant ARGs and cultured ARB were …


Surface Coating Method For Cement-Based Materials To Improve Chloride Ion Penetration Resistance Using Amine-Based Co2 Solvent, Seongho Han, Tae Hoon Han, Jae Hong Kim May 2024

Surface Coating Method For Cement-Based Materials To Improve Chloride Ion Penetration Resistance Using Amine-Based Co2 Solvent, Seongho Han, Tae Hoon Han, Jae Hong Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The application of coatings on concrete surfaces serves as a protective shield, guarding the structure against chlorides and averting corrosion of the reinforcement, consequently enhancing its durability. This study investigates the resistance of cement mortar samples to chloride ion penetration when coated with an amine-based carbon dioxide (CO2) solvent. Various factors, including monoethanolamine (MEA) concentrations of 1, 10, and 30 wt.%; water-to-cement ratios (w/cm) of 0.35, 0.4, and 0.5; coating timings on day 3 and day 27; and pre-conditioning methods such as air drying, are investigated for their impact on the performance of chloride penetration resistance. Specifically, pre-conditioning significantly enhanced …


Maximization Of Brackish Water Productivity For The Sustainable Production Of Striped Catfish (Pangasianodon Hypophthalmus) And Grain Sorghum (Sorghum Bicolor (L.) Moench) Cultivated Under An Integrated Aquaculture–Agriculture System, Fahad Kimera, Muziri Mugwanya, Khaled Madkour, Mahmoud A.O. Dawood, Hani Sewilam May 2024

Maximization Of Brackish Water Productivity For The Sustainable Production Of Striped Catfish (Pangasianodon Hypophthalmus) And Grain Sorghum (Sorghum Bicolor (L.) Moench) Cultivated Under An Integrated Aquaculture–Agriculture System, Fahad Kimera, Muziri Mugwanya, Khaled Madkour, Mahmoud A.O. Dawood, Hani Sewilam

Faculty Journal Articles

Freshwater scarcity, salinity, and poor soil fertility are the major challenges affecting both food and feed productions in arid and semi-arid regions of the world. Utilization of brackish water in the production of saline-tolerant fish and valuable field crops under an integrated system is promising in the maximization of yield per crop. The aim of this study, therefore, was to (1) assess the effect of saline aquaculture wastewater on the growth, yield, forage quality, and nutritive composition of sorghum seeds and (2) assess the effect of different water qualities on the survival, growth performance, and health status of Pangasianodon hypophthalmus. …


Developing Guidelines For The Use Of Lightweight Materials In Culvert Preservation, Charlie Sun, Kean H. Ashurst Jr. May 2024

Developing Guidelines For The Use Of Lightweight Materials In Culvert Preservation, Charlie Sun, Kean H. Ashurst Jr.

Kentucky Transportation Center Research Report

This study addresses challenges that arise during highway embankment construction on road widening projects when additional fill is placed above existing culverts. Researchers conducted reduced-scale model laboratory tests to simulate culvert behavior under different loading conditions and to determine how well lightweight materials (LWMs) perform when subjected to changing loads. Testing showed that proximity of LWM to the culvert’s top surface strongly influences the magnitude of strain reductions or increases. Placing LWMs with relatively low elastic modulus closer to the culvert’s top surface led to reduced culvert ceiling strain and increased culvert wall strain. LWMs with relatively high elastic modulus …


Addressing Multimodal Transportation Needs Through Complete Streets Implementation, Eirini Stavropoulou, Nikiforos Stamatiadis, William Staats, Teng Wang, Reginald Souleyrette May 2024

Addressing Multimodal Transportation Needs Through Complete Streets Implementation, Eirini Stavropoulou, Nikiforos Stamatiadis, William Staats, Teng Wang, Reginald Souleyrette

Kentucky Transportation Center Research Report

Since the early 2000s, over 1,600 transportation agencies in the United States have adopted Complete Streets policies. Recently, the Kentucky Transportation Cabinet (KYTC) published its Complete Streets, Roads, and Highways Manual, which aims to implement a safe and equitable transportation system throughout the state, as well as a Complete Streets policy. The manual and policy offer guidance on integrating Complete Streets principles into road design, however, KYTC currently lacks tools or methods to evaluate how well specific projects address Complete Streets goals. This is problematic because systematic assessments are needed to effectively prioritize projects and allocate scarce funding. Based …


Estimation Of Benefits From Pedestrian And Bicycle Improvements, Dionysios Tzamakos, Nikiforos Stamatiadis, William Staats, Teng Wang, Reginald Souleyrette May 2024

Estimation Of Benefits From Pedestrian And Bicycle Improvements, Dionysios Tzamakos, Nikiforos Stamatiadis, William Staats, Teng Wang, Reginald Souleyrette

Kentucky Transportation Center Research Report

Delivering safe mobility for all users of the transportation system is a key priority of the Kentucky Transportation Cabinet (KYTC). Because many system users rely on pedestrian and bicycle facilities, it is critical for KYTC to balance pedestrian and bicycle facility accommodations with those for motorized users. Currently, the Strategic Highway Investment Formula for Tomorrow (SHIFT) — the Cabinet’s systematic approach to scoring and prioritizing proposed roadway projects — awards up to five points (out of a possible total of 100) for pedestrian and bicycle projects. But the agency lacks a robust method for estimating the benefits of pedestrian and …


Modeling Inflation Transmission Among Different Construction Materials, Mohamad Abdul Nabi, Islam H. El-Adaway, Rayan H. Assaad May 2024

Modeling Inflation Transmission Among Different Construction Materials, Mohamad Abdul Nabi, Islam H. El-Adaway, Rayan H. Assaad

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Cost estimating in the construction industry is challenging due to the high uncertainty associated with the supply chain, especially after the COVID-19 pandemic. Some research studies have addressed such problems by developing models that predict material cost. In fact, all material can be interconnected and interrelated with lead-lag relationships such that any inflation in one material's price can be associated with inflation in other materials' prices, referred to as transmission of inflation. Despite the latter, none of the existing studies have investigated inflation transmission among all construction materials. This paper fills this knowledge gap. The authors used a multistep research …


A Review Of Whipple Shield Ballistic Limit Equations, S. Ryan, W. (William) P. Schonberg May 2024

A Review Of Whipple Shield Ballistic Limit Equations, S. Ryan, W. (William) P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Ballistic limit equations (BLEs) are semi-analytical expressions used to predict the risk posed by micrometeoroid and orbital debris (MMOD) impacts on a spacecraft. A foundational BLE, known as the new non-optimum (NNO) equation was published by Eric Christiansen of NASA Johnson Space Center in 1990 for application on Whipple shields – two-plate configurations consisting of a thin sacrificial plate located at some standoff in front of the spacecraft pressure hull or structural wall. Today, BLEs for almost all multi-plate spacecraft structures, e.g., honeycomb sandwich panels, monolithic structures with thermal insulation blankets, etc., are based on the NNO Whipple BLE. We …


Balancing Environmental Clearances With Construction Work Zone Needs, Chris Van Dyke, Steve Waddle, Ying Li May 2024

Balancing Environmental Clearances With Construction Work Zone Needs, Chris Van Dyke, Steve Waddle, Ying Li

Kentucky Transportation Center Research Report

On small, single-span bridge projects (< 100 feet), the Kentucky Transportation Cabinet (KYTC) during project development works to establish an environmentally clear area (ECA) large enough to accommodate contractor operations. An adequately sized ECA gives contractors sufficient room to have materials delivered, park vehicles, store materials, and maneuver equipment around the project site (e.g., cranes, drill rig). If a contractor finds an ECA is too small to support their operations, they are responsible for obtaining additional environmental clearances. Clearing additional areas following the project award can slow down project delivery. To reduce the likelihood of contractors needing to enlarge an ECA, this report includes four documents KYTC can implement immediately to streamline and clarify the environmental clearances process. They include a checklist that project managers can use to coordinate the work of project team members and verify environmental clearances are on track, a combined environmental clearances workflow and best practices document for use by environmental subject-matter experts (SMEs), proposed language that can be inserted into project proposals that describes the environmental clearance process and specifies materials the Cabinet will hand off to contractors showing the location of the ECA, and a one-page explainer for contractors describing the environmental clearances process. Taken together, these deliverables emphasize the importance of early and ongoing coordination among project team members, clearing as much area as practical in and around bridges, and being transparent with contractors about their responsibilities.


Unhsc Performance Curve And O&M Tracking Calculator, Daniel Macadam May 2024

Unhsc Performance Curve And O&M Tracking Calculator, Daniel Macadam

UNH Stormwater Center

No abstract provided.


Engineering Sustainable Bridge Deck Rehabilitation: Evaluating Mechanical And Electro-Chemical Properties Of Rapid-Set Patching Materials And Their Influence On Repair Durability, James Roberts May 2024

Engineering Sustainable Bridge Deck Rehabilitation: Evaluating Mechanical And Electro-Chemical Properties Of Rapid-Set Patching Materials And Their Influence On Repair Durability, James Roberts

All Theses

As the state of the US infrastructure continues to deteriorate over time, a prominent issue especially in the field of reinforced concrete structures has been the ability to properly rehabilitate and extend the design service life of these structures. A majority of our existing reinforced concrete bridges were built in the construction boom during the 60’s, 70’s and 80’s, and were originally designed with a service life of approximately 50 years, thus showing that many structures are close to or have already exceeded their intended service life. Additionally, with a poor history of government infrastructure funding, it is seen to …


Dynamics Of Link Importance Across Flood Disaster Phases And Flood Impacts On Operation Of An Industry, Navin Bhatta May 2024

Dynamics Of Link Importance Across Flood Disaster Phases And Flood Impacts On Operation Of An Industry, Navin Bhatta

All Theses

Transportation damage and disruptions will become increasingly common as the frequency of floods increases due to climate change. Given the size and cost of the transportation network construction, communities' mitigation measures should be supported by evaluations that cover both normal and disaster management phases. This thesis examines the criticality of road segments in the normal, flood response, and recovery phases, considering the effects on emergency services, healthcare, industry, education, recreation, and transit and analyses that whether a flood disrupts the operational trips of a company in Anderson County, South Carolina. A 100-year event and a 500-year flood event provides context …