Engineering Commons^™

Behavior Of Prestressed Concrete Bridges With Closure Pour Connections And Diaphragms, Gercelino Ramos

Masters Theses

Accelerated Bridge Construction (ABC) has gained substantial popularity in new bridge construction and bridge deck replacement because it offers innovative construction techniques that result in time and cost savings when compared to traditional bridge construction practice. One technology commonly implemented in ABC to effectively execute its projects is the use of prefabricated bridge components (precast/prestressed bridge components). Precast/prestressed bridge components are fabricated offsite or near the site and then connected on-site using small volume closure pour connections. Diaphragms are also commonly used to strengthen the connection between certain prefabricated components used in ABC, such as beam elements. Bridges containing closure …

The Promise Of Vr Headsets: Validation Of A Virtual Reality Headset-Based Driving Simulator For Measuring Drivers’ Hazard Anticipation Performance, Ganesh Pai Mangalore

Masters Theses

The objective of the current study is to evaluate the use of virtual reality (VR) headsets to measure driving performance. This is desirable because they are several orders of magnitude less expensive and, if validated, could greatly extend the powers of simulation. Out of several possible measures of performance that could be considered for evaluating VR headsets, the current study specifically examines drivers’ latent hazard anticipation behavior both because it has been linked to crashes and because it has been shown to be significantly poorer in young drivers compared to their experienced counterparts in traditional driving simulators and in open …

Sustainable Travel Incentives Optimization In Multimodal Networks, Hossein Ghafourian

Masters Theses

Tripod, an integrated bi-level transportation management system, is a smartphone application from the potential user’s point of view which would be instantly accessed prior to performing the trip. Since there are constantly several alternatives for any trip, Tripod considers a series and combination of various parameters, including departure time, mode and route, and rewards for each alternative with a number of redeemable points for goods and services called “Tokens”. The framework responsible for computing the optimized number of tokens awarded to the set of available alternatives in order to minimize the system-wide energy consumption under a constrained Token budget, is …

Kc 4.3: Rural Landscapes Of The 20th Century, Stefania Landi, Concetta Lenza, Denise Ulivieri

ISCCL Scientific Symposia and Annual General Meetings // Symposiums scientifiques et assemblées générales annuelles de l'ISCCL // Simposios científicos yy las Asambleas Generales Anuales

During the 20^th Century, rural landscapes all over the world underwent rapid transformations as a result of many factors - including new socio-political and economic conditions, new agricultural practices and the mechanization of agriculture - resulting in radical transformations of land uses and in the introduction of new infrastructures and facilities, necessary for the storage and distribution of an ever increasing amount of products. Based on the existing documents and bibliography relevant to the topic (ICOMOS-IFLA, Principles concerning rural landscapes as heritage, 2017; ICOMOS-ISC20C, Madrid-New Delhi Document. Approaches to the conservation of twentieth-century cultural heritage, 2017; Meeus, Wijermans, Vroom, …

Panel 1 Paper 1.3: Le Paysage Rural Patrimonial, Outil Et Projet Au Service De La Lutte Contre Le Réchauffement Climatique, Régis Ambroise

ISCCL Scientific Symposia and Annual General Meetings // Symposiums scientifiques et assemblées générales annuelles de l'ISCCL // Simposios científicos yy las Asambleas Generales Anuales

Cette intervention fait référence au paragraphe de la résolution19GA 2017/30 du Conseil International des Monuments et des Sites indiquant que « la 19° Assemblée générale de l’ICOMOS… salue l’adoption de l’accord de Paris et encourage tous les membres de l’ICOMOS à renforcer leurs efforts pour appuyer sa mise en œuvre et identifier les réponses qui s’appuient sur le patrimoine ou les paysages culturels… ». Elle prend l’exemple de la façon dont les paysages de terrasses ont été abordés ces dernières années dans trois situations différentes : en France, dans le Guizhou en Chine et dans le Priorat en Espagne.

En …

Finite Element Simulation Of Bonded And Mechanically Anchored Shear Interfaces Of Externally Applied Frp Sheets To Concrete And Wood-Concrete Composites, Alaa Al-Sammari

Doctoral Dissertations

Composite construction is prevalent in advanced structural systems where components of different materials are combined in the same structure to improve the performance of strong and economic structural sections. Maintaining continuity between the different structural components to produce monolithic structural behavior is challenging because of differences in the mechanical properties of these materials in terms of stiffness, strength, and ductility. The different components of the composite section are typically joined using adhesives and/or mechanical anchors to produce partial or full composite action. This dissertation discusses two types of shear interfaces intended to result in structural composite behavior. The first type …

Northeastern Species In Hybrid Cross Laminated Timber, Hamid Kaboli

Doctoral Dissertations

Known in the building industry throughout the world, Cross Laminated Timber (CLT) is a massive timber building material with outstanding structural, fire, and seismic properties. CLT is a cost-competitive, sustainable construction material is a good candidate as a substitute material for concrete, masonry, and steel, in mid-rise and high-rise buildings. CLT is perpendicular layers of dimensional lumbers usually laminated together and forming a massive structural panel. This dissertation explores the viability of utilizing Massachusetts grown Eastern Hemlock and Eastern White Pine in CLT panels as pure or in conjunction with other high-value wood products. 59% of Massachusetts’ lands are covered …

Evaluation Of The Effect Of Bottom Bar Splice Location On Performance Of Beams In Reinforced Concrete Perimeter Frames, Jorge Rivera Cruz

Doctoral Dissertations

The American Concrete Institute (ACI) Building Code Requirements for Structural Concrete and Commentary (ACI 318-14) indirectly accounts for resistance to progressive collapse by providing requirements for structural integrity in concrete structures. ACI 318-14 structural integrity requirements are intended to provide alternate load paths so that progressive collapse is avoided in the event of the unintended loss of an interior support. ACI 318-14 §9.7.7.5 requires that splices of structural integrity reinforcement be designed as Class B splices near mid-span for top reinforcement and near the support for bottom reinforcement. However, ACI 318-14 does not provide a clear definition for the support …

Laboratory Study Of The Geotechnical Properties Of Abraded Railway Ballast With Natural And Clay Mix Fouling, Andrew Rohrman

Doctoral Dissertations

With 140,000 miles of active track, railroad freight is the largest method of transporting goods in the United States. An important component of the railroad substructure is the gravel-size aggregate placed below the tracks, called ballast. The ballast is responsible for draining water away from the track, resisting forces from traffic loading, maintaining track position, and reducing loads to acceptable pressures for the subgrade. Ballast is typically selected to be highly angular and uniformly graded, but these characteristics are constantly changing under dynamic traffic loading. As the ballast is loaded, the particles abrade against each other, grinding off stone dust …

Mechanical Performance Of Structural Systems With Missing Members: From Buildings To Architected Materials, Panagiotis Pantidis

Doctoral Dissertations

Structural systems are potentially subjected to damage initiating scenarios throughout the course of their service time. Depending on the nature and extent of the damaging event, they may experience significant reduction or even complete loss of their mechanical performance. This dissertation delves into the mechanics of structural systems under the notion of missing members from their domain, investigating types of structural systems: a) multi-story steel framed buildings, and b) materials with a truss-lattice microstructure. Part I of the dissertation investigates the performance of multi-story steel framed buildings under a column removal scenario, developing an analytical framework for their quasi-static robustness …

Equity And Efficiency In Multi-Modal Transportation Systems, Nicholas M. Fournier

Doctoral Dissertations

The land-use pattern for many cities is a central business district surrounded by sprawling suburbs. This pattern can lead to an inefficient and congestion-prone transportation system due to a reliance on automobiles, because high-capacity transit is not efficient in low-density areas where insufficient travelers can access transit. This also poses an equity concern as the monetary cost of faster and more expensive travel disproportionately burdens low income travelers. This dissertation presents a deterministic approximation of a discrete choice model for mixed access and mainline transportation modes, meaning that travelers may use different modes to access a mainline system, such as …

Modeling The Effect Of New Commuter Bus Service On Demand And The Impact On Ghg Emissions: Application To Greater Boston, Christopher Lyman

Masters Theses

The transportation sector is considered one of the major contributors to greenhouse gas (GHG) emissions in metropolitan areas, and any efforts to reduce these emissions requires strategic management of multiple transportation modes. This paper presents a method to identify opportunities to reduce GHG emissions by expanding commuter bus services and incentives to shift commuters from private cars to transit. The approach uses a nested multinomial logit model for mode choice in a region that includes driving alone, carpooling, walking, cycling, and using four possible transit modes (ferry, commuter rail, rapid transit and bus) by walk access or driving access. A …

The Success, Morphology, And Performance Of Oxygenic Photogranules Under Light-Induced Stress Conditions, Samuel Downes

Environmental & Water Resources Engineering Masters Projects

No abstract provided.

Modeling And Optimizing Routing Decisions For Travelers And On-Demand Service Providers, Xinlian Yu

Doctoral Dissertations

This thesis investigates the dynamic routing decisions for individual travelers and on-demand service providers (e.g., regular taxis, Uber, Lyft, etc). For individual travelers, this thesis models and predicts route choice at two time-scales: the day-to-day and within-day. For day-to-day route choice, methodological development and empirical evidences are presented to understand the roles of learning, inertia and real-time travel information on route choices in a highly disrupted network based on data from a laboratory competitive route choice game. The learning of routing policies instead of simple paths is modeled when real-time travel information is available, where a routing policy is defined …

A Multiline Anchor Concept For Floating Offshore Wind Turbines, Casey Fontana

Doctoral Dissertations

Floating offshore wind turbines (FOWTs) hold great potential for the renewable energy industry, but capital costs remain high. In efforts to increase FOWT substructure efficiency and reduce costs, this thesis investigates a novel multiline anchor concept in which FOWTs share anchors instead of being moored separately. The goal of this thesis is to evaluate the force dynamics, design, and potential cost reduction of the system. Anchor forces are simulated using the NREL 5 MW reference turbine and OC4-DeepCwind semisubmersible platform, and multiline anchor force is computed as the vector sum of the contributing mooring line tensions. The use of a …

Applications Of Machine Learning Methods In Macroscopic Crash Analysis For Transportation Safety Management, Somaye Garmroudi Dovirani

Doctoral Dissertations

Transportation Safety Planning (TSP) is a statewide-scale tool and combines transportation planning processes with safety aims to increase safety and reduce transportation fatalities and injuries. Traffic safety, which continues to remain a critical issue worldwide, has led to a myriad of modeling techniques to improve analytical capabilities with respect to crash modeling and prediction. State and metropolitan transportation planning processes must be consistent with Strategic Highway Safety Plans. This research aims to identify models and methods to improve the ability to capture variables that have the most significant impact on traffic safety through crash prediction modeling. In order to achieve …

Application Of Ground Penetrating Radar For Use In Thermal Conductivity Site Investigations, Aaron J. Rubin

Doctoral Dissertations

Measurement of soil thermal conductivity in-situ is important for many practical geotechnical and civil engineering applications. However, for a variety of reasons it can be difficult to measure in-situ. A novel method to estimate the thermal conductivity of sands based on electrical relative permittivity (dielectric constant) measurements and GPR data is presented. First, an analytical model to estimate thermal conductivity of soils was developed and validated using a database of thermal conductivity measurements. The new thermal conductivity model was then compared to existing models using a larger database of new and pervious thermal conductivity measurements conducted on a wide range …

Analysis Of Adhesive Anchorage Systems Under Extreme In-Service Temperature Conditions, Rachel Wang

Masters Theses

Adhesive anchorage systems have found widespread use in structural applications, including bridge widening, concrete repair and rehabilitation, and barrier retrofitting. Because these applications typically require adhesive anchorage systems to be installed outdoors, the effects of climate conditions and day-to-day temperature fluctuations on adhesive behavior and performance should be considered. The purpose of this thesis is to simulate pullout tests of adhesive anchorage systems for threaded rod and reinforcing bars and to emulate effects under various temperature conditions through the use of finite element analysis. Results from the finite element simulation are then compared to the physical tests conducted at UMass …

Performance Of Concrete Tunnel Systems Subject To Fault Displacement, Michael Morano

Masters Theses

A Finite Element Analysis (FEA) investigation of concrete tunnel systems traversing seismic faults is carried out to determine how to effectively mitigate the stresses induced in the liner when subject to fault displacement. A parametric study of various fault parameters, both in the damage zone and competent rock, is carried out to determine the site conditions which induce the most stress on the tunnel liner system. Results indicate that friction angle, cohesion, and elastic modulus of fault zones have varying effects on the stresses induced on the liner. The width of damage zone and expected displacements are also investigated and …

High Fidelity Modeling Of Cold-Formed Steel Single Lap Shear Screw Fastened Connections, Rita Kalo

Masters Theses

Cold-formed steel connections are commonly fastened using self-tapping self-drilling screws. The behavior of these connections can differ based on the screw manufacturer or the cold-formed steel product used, both of which have a large selection available for use in industry. Because of their popularity and the many possible variations of these connections, researchers have frequently tested screw connections to characterize their behavior. However, repeatedly conducting this type of experiment is time consuming and expensive. Therefore, the purpose of this work was to create finite element models that can successfully predict the behavior of single lap shear screw connections, a common …

Evaluation Of New Methods For Determining The Minimum And Maximum Index Densities Of Sand, Hossein Ganji

Geotechnical Engineering Masters Projects

This thesis presents the results of a laboratory testing program that evaluated the applicability of a new-established method for determining minimum and maximum dry density values by Norwegian Geotechnical Institute (NGI). Seven fine to medium grained cohesionless sand batches with different inclusion of fines content were selected for a series of testing programs in compliance with American Society for Testing and Materials (ASTM) and NGI recommendations. All three methods of ASTM D4254 – 16 and method 1B of ASTM D4253 – 16 were applied for minimum and maximum dry density determination, respectively. The results compared with the NGI minimum and …

Evaluation Of Helical Piles As Anchors For Floating Offshore Wind Turbine Foundation Systems, Martha Shannon Harris

Geotechnical Engineering Masters Projects

The development of floating offshore wind energy is essential for growth of the renewable energy industry, and to decrease the reliance on fossil fuels and emission of greenhouse gasses. Advances in ease of construction and installation of turbines can make the floating offshore wind industry more marketable and feasible on a large scale; this can in part be achieved by innovation in foundation anchoring systems.

This thesis presents an evaluation of helical pile foundations for offshore deep-water application as anchors for floating offshore wind systems with catenary mooring lines in clay and sandy soils. This research outlines the influence of …

Evaluation Of Two Real Time Methods For Assessing Thm Precursor Concentrations, Griffin Moriarty

Environmental & Water Resources Engineering Masters Projects

Conventional drinking water treatment generally requires maintenance of a disinfectant residual, most commonly free or combined chlorine. Since the discovery of disinfection byproducts (DBPs), utilities have relied on a broad range of water quality parameters to help them achieve compliance with DBP regulations. Most notably, dissolved organic carbon (DOC) and ultraviolet absorbance at 254 nm (UV254) have been used to assess DBP precursor levels in near-real time. These are often compared to actual system DBP concentrations or to results from laboratory DBP precursor tests resulting in a site-specific precursor-DBP model. The DOC or UV254 models are often inaccurate, requiring re-calibration, …

An Assessment Of Lead And Copper In School Drinking Water, Kaavya Raghavan Ram

Environmental & Water Resources Engineering Masters Projects

Metal contamination in drinking water, especially heavy metals such as lead, and corrosion issues, pose a threat to human health and have received increasing attention in recent years. This study reports on the results of ‘The Massachusetts Assistance Program for Lead in School Drinking Water’ and provides a better understanding of the dynamics of sampling protocols, premise plumbing and their influence on lead and copper concentrations. ‘The Massachusetts Assistance Program for Lead in School Drinking Water’ that was announced in April 2016, implemented tap-based water sampling for lead and copper at K-12 public schools and Early Education and Childcare centers …

Developing A Toolkit For Citizen Scientists' Evaluation Of Drinking Water Quality, Leighann D'Andrea

Environmental & Water Resources Engineering Masters Projects

This project evaluated tools for citizen science by assessing the potential to monitor drinking water quality at home with commercially sold, or off the shelf, test kits. The first objective was to compare the results of off the shelf test kits with laboratory-obtained values as performed in a controlled environment by trained laboratory personnel. The second objective was to provide potential citizen scientists with a selection of test kits to determine if they could successfully use the kits. These two objectives contributed to the end goal of understanding whether test kits on the market existed that could be used by …

Modeling Nature-Based Solutions For Climate Resilience, Mason Saleeba

Environmental & Water Resources Engineering Masters Projects

Riparian wetlands can serve as nature-based infrastructure that slow the rapid movement of water during high flow events. As the recurrence of high flow events increases due to global climate change, an improved understanding of the potential of wetland landscapes to provide flood mitigation is needed. This research addresses both the impacts of climate change and land cover on extreme flow events in the Otter Creek watershed in Vermont. The upstream portion of the basin is modeled with the Soil and Water Assessment Tool (SWAT) to investigate the impacts of climate change on extreme flow events. A Hydrologic Engineering Center's …

Over-Citing Or Under-Citing? A Gis-Based Analysis Of The Relationship Between Crashes And Citations, Mitchell Page

Transportation Engineering Masters Projects

In July of 2017, the Boston Globe published an article titled “Driving Through These Towns in Mass.? Watch Your Speed” [1] that among other elements, included a series of maps and a brief summary identifying Massachusetts municipalities that had the most traffic violations issued between 2010 and 2016. The article stated that the Massachusetts State Police issued the most citations of any police agency in the state, and that many citations were given along major highways, especially Interstate 90 and major highways and routes that intersect it, such as Interstate 84 and Route 20. Despite the public attention-grabbing nature of …

Modelling The Surrogate Safety Of Various Left-Turn Phase Sequences, Rohith Prakash Panthangi

Transportation Engineering Masters Projects

Left-turns are the most complex maneuvers in a signalized intersection. Based on the flow of the traffic volume through a given intersection, the left-turn phasing may be controlled in various fashions such as: protected only, permissive only, and protected/permissive. Following the introduction of the flashing yellow arrow (FYA) to the 2009 Edition of the Manual on Uniform Traffic Control Devices (MUTCD), many state agencies have implemented these indications for their left-turn permissive movements. Similar to the existing circular green (CG) permissive indication, the FYA requires drivers to yield to oncoming vehicles before making their left-turn. However, given the novelty of …

Driver Performance Due To Unmanned Aerial System Applications In The Vicinity Of Surface Transportation, Alyssa M. Ryan

Transportation Engineering Masters Projects

Unmanned aerial systems (UAS), or drones, have become increasingly utilized for a myriad of applications in the vicinity of the roadway and can offer a low-cost alternative to many labor-intensive data collection techniques, including infrastructure inspection, roadway marking data collection, and more. To collect much of this data with a desired degree of accuracy, UAS must be flown near moving vehicles, pedestrians, and/or bicyclists. However, UAS, and their pilot/crew, have the potential to be a distraction to drivers. A study by Hurwitz et al. suggests that UAS operations are more distracting to drivers as the UAS traverses closer to the …

Driver Behaviour And Performances On In-Vehicle Display Based Speed Compliance, Aamani Ramanathan Parthasarthy

Transportation Engineering Masters Projects

Traffic Control Devices (TCDs) are integral to driver-to-infrastructure (D2I) and vehicleto- infrastructure (V2I) interactions. The non-conformation (or non-perception) with signage on the part of the driver leads to several compounded safety problems. The need exists for a more robust, low-cost, and user-centric mechanism of delivering information to the driver that can directly bear on the safety of the driver. Technology has now advanced to the point where we can deliver information from a real-world physical environment to the driver in a non-invasive manner using holographic display [1]. With this rapid advancement in-vehicle display (IVD) technology, the transportation industry must undergo …