Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Engineering (8)
- Mechanical Engineering (4)
- Engineering Science and Materials (2)
- Materials Science and Engineering (2)
- Mechanics of Materials (2)
-
- Aerospace Engineering (1)
- Automotive Engineering (1)
- Civil and Environmental Engineering (1)
- Education (1)
- Environmental Health and Protection (1)
- Environmental Sciences (1)
- Medicine and Health Sciences (1)
- Occupational Health and Industrial Hygiene (1)
- Other Education (1)
- Other Engineering (1)
- Other Mechanical Engineering (1)
- Physical Sciences and Mathematics (1)
- Public Health (1)
- Structural Engineering (1)
- Institution
Articles 1 - 12 of 12
Full-Text Articles in Entire DC Network
Non-Traditional Shape Gfrp Rebars For Concrete Reinforcement, Guillermo G. Claure
Non-Traditional Shape Gfrp Rebars For Concrete Reinforcement, Guillermo G. Claure
Open Access Dissertations
The use of glass-fiber-reinforced-polymer (GFRP) composites as internal reinforcement (rebars) for concrete structures has proven to be an alternative to traditional steel reinforcement due to significant advantages such as magnetic transparency and, most importantly, corrosion resistance equating to durability and structural life extension. In recent years, the number of projects specifying GFRP reinforcement has increased dramatically leading the construction industry towards more sustainable practices. Typically, GFRP rebars are similar to their steel counterparts having external deformations or surface enhancements designed to develop bond to concrete, as well as having solid circular cross-sections; but lately, the worldwide composites industry has taken …
Design Of Gfrp Reinforcement For Concrete Bridge Structural Components, Valentino Rinaldi
Design Of Gfrp Reinforcement For Concrete Bridge Structural Components, Valentino Rinaldi
Open Access Theses
The demand for the development of a more efficient and durable transportation infrastructure is among the priorities of highway authorities worldwide. In the United States, the economic impact of steel corrosion for concrete highway bridges is estimated to exceed 15 percent of the total annual costs. Glass fiber reinforced polymer (GFRP) is highly suitable as internal reinforcement for structures subjected to corrosive environments. A number of projects have demonstrated its viability as an alternative reinforcement for bridge decks and design provisions are currently available in several countries. Nowadays, manufacturers can produce standard bar bends which can be applied to design …
Effect Of Manufacturing Processes On The Loss Factor And Other Mechanical Properties Of Kenaf Fiber-Reinforced Composites, Brian P. Spackman
Effect Of Manufacturing Processes On The Loss Factor And Other Mechanical Properties Of Kenaf Fiber-Reinforced Composites, Brian P. Spackman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The characteristics essential for manufacturing parts and products are not well known for natural fiber-reinforced composite materials. Natural fibers display properties similar to glass fibers, and present a more environmentally friendly option for manufacturing composite materials. This research investigates various parameters in the manufacture of kenaf fiber-reinforced composites including cure time, density, matrix hardener ratio, surface treatment, and fiber length and examines the effect they have on mechanical properties of the composite material. Several samples were created and subjected to a vibrational test. Using known relationships, mechanical properties were extracted from the test results. Samples were found to exhibit repeatable …
Modeling Of Debonding And Crack Propagation In Fibrous Composites Using A Discontinuous Galerkin Approach, Wesley Michael Hicks
Modeling Of Debonding And Crack Propagation In Fibrous Composites Using A Discontinuous Galerkin Approach, Wesley Michael Hicks
Masters Theses
A recently proposed Discontinuous Galerkin (DG) method for modeling debonding and fracture within the context of the finite element method is investigated for problems relating to fiber reinforced composites, namely fiber-matrix interfacial debonding which progresses to matrix fracture. The results are then compared against an existing intrinsic cohesive zone method and a hybrid Discontinuous Galerkin method. The results show that the method can eliminate the problem of artificial compliance that is associated with intrinsic cohesive zone models. Eliminating this stiffness has the positive effect of removing user-defined numerical parameters that are not actually present in the physical system. A key …
Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden
Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden
Dissertations, Master's Theses and Master's Reports - Open
The thermoset epoxy resin EPON 862, coupled with the DETDA hardening agent, are utilized as the polymer matrix component in many graphite (carbon fiber) composites. Because it is difficult to experimentally characterize the interfacial region, computational molecular modeling is a necessary tool for understanding the influence of the interfacial molecular structure on bulk-level material properties. The purpose of this research is to investigate the many possible variables that may influence the interfacial structure and the effect they will have on the mechanical behavior of the bulk level composite. Molecular models are established for EPON 862-DETDA polymer in the presence of …
The Design And Development Of Novel Metal Oxide Nanocomposites For Sunlight Driven Water Cleaning, Kanlaya Pingmuang
The Design And Development Of Novel Metal Oxide Nanocomposites For Sunlight Driven Water Cleaning, Kanlaya Pingmuang
University of Wollongong Thesis Collection 1954-2016
Photocatalytic degradation of environmental pollutants using a visible light-driven photocatalysts has attracted much attention in order to effectively utilize the majority of the solar energy. Bismuth vanadate (BiVO4) has been one of the semiconducting materials used as visible light driven photocatalysts due to its physical and chemical properties and remarkable photocatalytic performance. However, the individual BiVO4 exhibits low efficiency in photodegradation of organic pollutants. The recombination of photogenerated electron and hole pairs and redox potentials of the generated electron are considered as the factors that affect to its photocatalytic efficiency. In this regard, the primary aims of this work are …
Mechanically Active Electrospun Materials, Jaimee Marie Robertson
Mechanically Active Electrospun Materials, Jaimee Marie Robertson
Dissertations - ALL
Electrospinning, a technique used to fabricate small diameter polymer fibers, has been employed to develop unique, active materials falling under two categories: (1) shape memory elastomeric composites (SMECs) and (2) water responsive fiber mats. (1) Previous work has characterized in detail the properties and behavior of traditional SMECs with isotropic fibers embedded in an elastomer matrix. The current work has two goals: (i) characterize laminated anisotropic SMECs and (ii) develop a fabrication process that is scalable for commercial SMEC manufacturing. The former ((i)) requires electrospinning aligned polymer fibers. The aligned fibers are similarly embedded in an elastomer matrix and stacked …
Computational Modelling And Surface Charachterization Of Interface In Polymer Composites By Atomic Force Microscopy, Daljeet Kumar Singh
Computational Modelling And Surface Charachterization Of Interface In Polymer Composites By Atomic Force Microscopy, Daljeet Kumar Singh
All ETDs from UAB
Polymer composites are used in numerous industries due to their high specific strength and high specific stiffness. Such composites have markedly different properties than both the reinforcement and the matrix. Of the several factors which govern the final property of the composite, the interface is the single most factor that influences the stress transfer mechanism from the fiber to the matrix. The interface bond strength is also influenced by the surface treatments applied to the fiber during spinning and weaving. The present study is an effort to characterize and model the fiber-matrix interface in polymer matrix composites. Finite element models …
Design And Analysis Of A Novel Latch System Implementing Fiber-Reinforced Composite Materials, Francisco Guevara
Design And Analysis Of A Novel Latch System Implementing Fiber-Reinforced Composite Materials, Francisco Guevara
Open Access Theses & Dissertations
The use of fiber-reinforced composite materials have increased in the last four decades in high technology applications due to their exceptional mechanical properties and low weight. In the automotive industry carbon fiber have become popular exclusively in luxury cars because of its high cost. However, Carbon-glass hybrid composites offer an effective alternative to designers to implement fiber-reinforced composites into several conventional applications without a considerable price increase maintaining most of their mechanical properties. A door latch system is a complex mechanism that is under high loading conditions during car accidents such as side impacts and rollovers. Therefore, the Department of …
Sound Attenuation Performance Of Fiber-Reinforced Polymer Composite Circumaural Hearing Protection Devices, Steven Christopher Augustine
Sound Attenuation Performance Of Fiber-Reinforced Polymer Composite Circumaural Hearing Protection Devices, Steven Christopher Augustine
USF Tampa Graduate Theses and Dissertations
Personnel who work on the flight deck of an aircraft carrier are exposed to extreme levels of jet engine noise often in excess of 140 decibels (dB). The current circumaural hearing protective devices (CAHPD) employed by flight deck crewmen are inadequate for the level of protection required for these extreme levels of noise. Fiber-reinforced thermoset polymer composite (FRPC) materials such as aramid fibers used in body armor, have high theoretical values of acoustic impedance due to a fundamentally high modulus of elasticity and may offer a superior level of hearing protection over original equipment (OE) thermoplastic CAHPDs. The objective of …
Acoustic Emission Characteristics Of Damage Accumulation In Kevlar® 49 Composites, Eduardo Andrade
Acoustic Emission Characteristics Of Damage Accumulation In Kevlar® 49 Composites, Eduardo Andrade
Open Access Theses & Dissertations
Acoustic emission (AE) data attained during tensile testing of epoxy impregnated Kevlar® 49 (K/Ep) composite strands were reduced and analyzed to monitor progressive damage accumulation during the approach to tensile failure. The K/Ep material tested in this study was chosen due to its similarity to the material-of-construction used in composite overwrapped pressure vessels (COPVs) used on the NASA Space Shuttle Orbiter. Insight into the progressive microstructural degradation of K/Ep strands was gained by monitoring AE event rate and energy. Source location based on energy attenuation and arrival time data was used to differentiate between significant AE attributable to microstructural damage …
Composite Tie Rod Research, Design And Testing For Sae Baja, Amanda M. Nauman
Composite Tie Rod Research, Design And Testing For Sae Baja, Amanda M. Nauman
Williams Honors College, Honors Research Projects
Composite materials have become increasing popular in recent years. For the Baja SAE team, composites are typically only used for body panels. To grow as a team and to earn additional points in design competition, it was decided to explore composite use in mechanical applications, specifically for the tie rods. Research was conducted, looking into composite materials basics, types, and material properties. Additionally, manufacturing was explored, including a few projects separate from the tie rod application. 3D models were created after the materials were selected, and FEA analysis was conducted on the parts. Once theoretical testing was finished, the physical …