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2019

Composites

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Retrofit Of Corroded Corrugated Metal Culverts Using Gfrp Slip-Liner, Rahulreddy Chennareddy Dec 2019

Retrofit Of Corroded Corrugated Metal Culverts Using Gfrp Slip-Liner, Rahulreddy Chennareddy

Civil Engineering ETDs

Culverts are water conveyance structures, typically used to allow water flow and maintain a balance between the flow streams without interrupting structures such as highways and bridges. Corrugated metal pipes (CMPs) have been used as culverts in North America since the 1950s because of their low cost and simple construction method. Today, the corrosion of CMPs is a major problem faced by all U.S. Departments of Transportation. There is an urgent need to provide an efficient solution, one that is corrosion-resistant, to retrofit thousands of corroded CMPs across the country. High specific strength, high strength to weight ratio, corrosion resistance, …


Multi-Scale Analysis Of Multifunctional Composites And 3d Printed Polymers, Daniel Branden Perez Dec 2019

Multi-Scale Analysis Of Multifunctional Composites And 3d Printed Polymers, Daniel Branden Perez

Open Access Dissertations

Methods of multi-scale analysis through combined physical testing and computational FEM were used to investigate structural battery composites and 3D printed polymers. Multifunctional composite structural batteries are materials capable of storing electrical energy while providing structural rigidity. Two battery cell configurations were considered: a carbon paper based cell with copper and aluminum foils, and a woven carbon fiber-based battery with nickel and iron deposition coatings. Flexural simulations were performed through simulated and physical three-point bend testing. Unidirectional carbon fiber layers in the place of the carbon paper can lead to up to a 233.73 GPa stiffness, significantly greater than the …


Amorphous-Crystalline Brush Block Copolymers: Phase Behavior, Rheology And Composite Design, Gayathri Kopanati Oct 2019

Amorphous-Crystalline Brush Block Copolymers: Phase Behavior, Rheology And Composite Design, Gayathri Kopanati

Doctoral Dissertations

Bottlebrush block copolymers are polymers with chemically distinct polymer side chains grafted onto a common backbone. The unique architecture induced properties make these materials attractive for applications such as photonic materials, stimuli responsive actuators and drug delivery vehicles to name a few. This dissertation primarily investigates the phase transitions and rheological behavior of amorphous-crystalline bottlebrush brush block copolymers and their composites. The temperature induced phase behavior is investigated using time resolved synchrotron X-ray source. Irrespective of volume fraction and backbone length, the samples display strong segregation even at high temperatures (200 °C) and there is no accessible order-disorder transition in …


Effect Of Pyrolysis Conditions On Sewage Sludge Derived Biochars For High Value Composites Applications, Paola Giudicianni, Maurizio Troiano, Roberto Solimene, Raffaele Ragucci, Mauro Giorcelli, Alberto Tagliaferro, Mattia Bartoli Sep 2019

Effect Of Pyrolysis Conditions On Sewage Sludge Derived Biochars For High Value Composites Applications, Paola Giudicianni, Maurizio Troiano, Roberto Solimene, Raffaele Ragucci, Mauro Giorcelli, Alberto Tagliaferro, Mattia Bartoli

Bio-Char II: Production, Characterization and Applications

The economy of the whole wastewater treatment system is significantly burdened by the increasing amounts of sewage sludge due to the progressive implementation of the Urban Waste Water Treatment Directive 91/271/EEC and by the complexity of the treatments required for guaranteeing a safe handling and a proper end-of-life of the sludge. For this reason, thermal treatments of sewage sludge have been studied in the past for their efficient valorization in terms of energy and/or matter recovery. Among them, pyrolysis represents a viable route aiming at the recycling of resources without production of harmful substances to the humans or the environment. …


Molecular Weight And Thermal Properties Of Fiber Reinforced Polyamide-Based Composites Throughout The Direct Long-Fiber Reinforced Thermoplastic Process, Mingyu Yang Aug 2019

Molecular Weight And Thermal Properties Of Fiber Reinforced Polyamide-Based Composites Throughout The Direct Long-Fiber Reinforced Thermoplastic Process, Mingyu Yang

Electronic Thesis and Dissertation Repository

The D-LFT process is an efficient and cost-effective process and includes two twin-screwextruders, a conveyer, and a compression molding machine. It is imperative to understand how the process sequence affects molecular weight and thermal properties of composite materials during the D-LFT process. The main objective of this study was to characterize variation in molecular weight and thermal properties of two types of polyamide (PA)-based composite materials (glass fiber reinforced PA6 composites and carbon fiber reinforced PA66 composites) through the D-LFT process. Samples were taken from different locations along the D-LFT process and characterized using triple detection gel permeation chromatography (GPC), …


Adaptive Paddle Board, Alexander Holthaus, Alexander Holthaus, Garrett Holmes, Garett Jones Jun 2019

Adaptive Paddle Board, Alexander Holthaus, Alexander Holthaus, Garrett Holmes, Garett Jones

Mechanical Engineering

This Final Design Review (FDR) document outlines the Adaptive Paddle Board senior project, done by four Mechanical Engineering Students at California Polytechnic State University and provides detail on the project and what the team has accomplished. The goal was to create a universally adaptive paddle board that can be used by the Central California Adaptive Sports Center for a wide range of persons with disabilities. This document highlights current research from patents and existing products, details regarding customer specifications, results from concept generation, the manufacturing and testing that went into the final design, and the process taken to get there. …


Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin Jun 2019

Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin

Honors Theses

Structural health monitoring has the potential to allow composite structures to be more reliable and safer, then by using more traditional damage assessment techniques. Structural health monitoring (SHM) utilizes individual sensor units that are placed throughout the load bearing sections of a structure and gather data that is used for stress analysis and damage detection. Statistical time based algorithms are used to analyze collected data and determine both damage size and probable location from within the structure. While traditional calculations and life span analysis can be done for structures made of isotropic materials such as steel or other metals, composites …


C6 Wheels, Samuel L. Pizot, Luke Martin, Josh Warner, Jonah Levis Jun 2019

C6 Wheels, Samuel L. Pizot, Luke Martin, Josh Warner, Jonah Levis

Mechanical Engineering

This document details the C6 Wheels project being undertaken for senior design. The objective is to design and manufacture carbon fiber reinforced polymer wheels for the Cal Poly Formula Society of Automotive Engineers (FSAE) team. The wheel shells will be used on FSAE’s competition vehicles. FSAE requested the wheels to improve the handling characteristics of their vehicles by reducing the unsprung and rotational mass. They have attempted carbon fiber wheels previously but have not yet run any on their vehicles. FSAE specifically proposed the design of carbon fiber shells with an aluminum center as opposed to full carbon fiber wheels …


Tribology Of Wc Reinforced Sic Ceramics: Influence Of Counterbody, Sandan Kumar Sharma, B. Venkata Manoj Kumar, Young-Wook Kim Jun 2019

Tribology Of Wc Reinforced Sic Ceramics: Influence Of Counterbody, Sandan Kumar Sharma, B. Venkata Manoj Kumar, Young-Wook Kim

Friction

Hot pressed silicon carbide (SiC) composites prepared with 0, 10, 30 or 50 wt% tungsten carbide (WC) are subjected to dry sliding wear against WC-Co and steel ball. In particular an attempt has been made to answer the following important questions: (i) How does the load (from 5 to 20 N) effect sliding wear behaviour of SiC-ceramics against WC-Co and steel counterbodies? (ii) Is there any effect of WC content on friction and wear characteristics of SiC ceramics? (iii) Does the dominant material removal mechanism of SiC ceramics change with the addition of WC or counterbody? (iv) What is the …


Silk Fibroin And Hydroxyapatite Composites For Bioresorbable Bone Fixation Devices, Bryant Heimbach Apr 2019

Silk Fibroin And Hydroxyapatite Composites For Bioresorbable Bone Fixation Devices, Bryant Heimbach

Doctoral Dissertations

Every year there are approximately 9 million bone fractures in the United States, and 30% of these require an internal fixation device to help heal. Currently, the gold standard for fixation devices relies on the use of metals because of their high mechanical properties and bioinertness. However, metal implants often require a second surgery to remove them because they cause stress shielding and metal ion leaching. Current bioresorbable fixation devices on the market have poor mechanical properties and are limited to use in non-load-bearing applications (i.e. maxillofacial fractures). As such, there remains a gap in the fracture fixation devices on …


Vibration-Based In-Situ Detection And Quantification Of Delamination In Composite Plates, Hanfei Mei, Asaad Migot, Mohammad Faisal Haider, Roshan Joseph, Md Yeasin Bhuiyan, Victor Giurgiutiu Apr 2019

Vibration-Based In-Situ Detection And Quantification Of Delamination In Composite Plates, Hanfei Mei, Asaad Migot, Mohammad Faisal Haider, Roshan Joseph, Md Yeasin Bhuiyan, Victor Giurgiutiu

Faculty Publications

This paper presents a new methodology for detecting and quantifying delamination in composite plates based on the high-frequency local vibration under the excitation of piezoelectric wafer active sensors. Finite-element-method-based numerical simulations and experimental measurements were performed to quantify the size, shape, and depth of the delaminations. Two composite plates with purpose-built delaminations of different sizes and depths were analyzed. In the experiments, ultrasonic C-scan was applied to visualize the simulated delaminations. In this methodology, piezoelectric wafer active sensors were used for the high-frequency excitation with a linear sine wave chirp from 1 to 500 kHz and a scanning laser Doppler …


Vibration-Based In-Situ Detection And Quantification Of Delamination In Composite Plates, Hanfei Mei, Asaad Migot, Mohammad Faisal Haider, Roshan Joseph, Md Yeasin Bhuiyan, Victor Giurgiutiu Apr 2019

Vibration-Based In-Situ Detection And Quantification Of Delamination In Composite Plates, Hanfei Mei, Asaad Migot, Mohammad Faisal Haider, Roshan Joseph, Md Yeasin Bhuiyan, Victor Giurgiutiu

Faculty Publications

This paper presents a new methodology for detecting and quantifying delamination in composite plates based on the high-frequency local vibration under the excitation of piezoelectric wafer active sensors. Finite-element-method-based numerical simulations and experimental measurements were performed to quantify the size, shape, and depth of the delaminations. Two composite plates with purpose-built delaminations of different sizes and depths were analyzed. In the experiments, ultrasonic C-scan was applied to visualize the simulated delaminations. In this methodology, piezoelectric wafer active sensors were used for the high-frequency excitation with a linear sine wave chirp from 1 to 500 kHz and a scanning laser Doppler …


Wet Lay-Up Technique For Manufacturing Of Advanced Laminated Composites, Abdel-Hamid Mourad, Nizar Zaaroura, Nizamudeen Cherupurakal Mar 2019

Wet Lay-Up Technique For Manufacturing Of Advanced Laminated Composites, Abdel-Hamid Mourad, Nizar Zaaroura, Nizamudeen Cherupurakal

Karbala International Journal of Modern Science

Incorporation of nanofillers into laminated composites is expected to produce a material with improved performance for many potential industrial applications. The focus of this work is to produce advanced composites by simple wet lay-up technique. The impact of adding three different nanofillers (multi-wall carbon nanotubes (MWCNT), silicon carbide (SiC) and aluminum oxide (Al2O3),) on the thermal and mechanical stability of woven Kevlar KM2Plus/epoxy composites was investigated. Silicon carbide and aluminum oxide were added at different weight percentages up to 3wt%, whereas the addition of multi-wall carbon nanotubes was limited to 1wt%. The mechanical behavior was evaluated through three-point bending tests. …


Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce Mar 2019

Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce

Joshua M. Pearce

In order to assist researchers explore the full potential of distributed recycling of post-consumer polymer waste, this article describes a recyclebot, which is a waste plastic extruder capable of making commercial quality 3-D printing filament. The device design takes advantage of both the open source hardware methodology and the paradigm developed by the open source self-replicating rapid prototyper (RepRap) 3-D printer community. Specifically, this paper describes the design, fabrication and operation of a RepRapable Recyclebot, which refers to the Recyclebot’s ability to provide the filament needed to largely replicate the parts for the Recyclebot on any type of RepRap 3-D …


Investigation Of Design, Manufacture, Analysis, And Test Of A Composite Connecting Rod Under Compression, Thomas Juhl Rohrbach Mar 2019

Investigation Of Design, Manufacture, Analysis, And Test Of A Composite Connecting Rod Under Compression, Thomas Juhl Rohrbach

Master's Theses

Composite materials hold great potential for the replacement of traditional materials in machines utilized on a daily basis. One such example is within an engine block assembly where massive components inherently reduce the efficiency of the system they constitute. By replacing metal elements such as connecting rods, cylinder caps, or a crank shaft with composite alternatives, a significant increase in performance may be achieved with respect to mechanical strength, thermal stability, and durability, while also reducing mass. Exploration of this technology applied to a connecting rod geometry was investigated through a combination of process development, manufacturing, numerical analysis and testing. …


Designed Conducting Polymer Composites That Facilitate Long-Lived, Light-Driven Oxygen And Hydrogen Evolution From Water In A Photoelectrochemical Concentration Cell (Pecc), Mohammed Alsultan, Khalid Zainulabdeen, Pawel W. Wagner, Gerhard F. Swiegers, Holly Warren Jan 2019

Designed Conducting Polymer Composites That Facilitate Long-Lived, Light-Driven Oxygen And Hydrogen Evolution From Water In A Photoelectrochemical Concentration Cell (Pecc), Mohammed Alsultan, Khalid Zainulabdeen, Pawel W. Wagner, Gerhard F. Swiegers, Holly Warren

Australian Institute for Innovative Materials - Papers

Light-driven water-splitting to generate hydrogen and oxygen from water is typically carried out in an electrochemical cell with an external voltage greater than 1.23 V applied between the electrodes. In this work, we examined the use of a concentration/chemical bias as a means of facilitating water-splitting under light illumination without the need for such an externally applied voltage. Such a concentration bias was created by employing a pH differential in the liquid electrolytes within the O2-generating anode half-cell and the H2-generating cathode half-cell. A novel, stretchable, highly ion-conductive polyacrylamide CsCl hydrogel was developed to connect the two half-cells. The key …


Selective Atomic-Level Etching On Short S-Glass Fibres To Control Interfacial Properties For Restorative Dental Composites, Kiho Cho, Guannan Wang, Raju Raju, Jian Fang, Ginu Rajan, Martina Stenzel, Paul Farrar, Gangadhara B. Prusty Jan 2019

Selective Atomic-Level Etching On Short S-Glass Fibres To Control Interfacial Properties For Restorative Dental Composites, Kiho Cho, Guannan Wang, Raju Raju, Jian Fang, Ginu Rajan, Martina Stenzel, Paul Farrar, Gangadhara B. Prusty

Faculty of Engineering and Information Sciences - Papers: Part B

Interfacial bonding between fibre and matrix is most critical to obtain enhanced mechanical properties of the resulting composites. Here we present a new surface tailoring method of selective wet etching and organosilicon monomers (3-(Trimethoxysilyl) propyl methacrylate, TMSPMA) deposition process on the short S-Glass fibre as a reinforcing material, resulting in increased mechanical retention and strong chemical bonding between glass fibres and polymer resin (a mixture of triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA) monomers). The effect of surface modification on fibre matrix interfacial strength was investigated through microdroplet tests. An S-Glass fibre treated with piranha solution (a mixture of …


Bending Response Of Timber Mortise And Tenon Joints Reinforced With Filler-Modules And Frp Gussets, Andrew Robert Pacifico Jan 2019

Bending Response Of Timber Mortise And Tenon Joints Reinforced With Filler-Modules And Frp Gussets, Andrew Robert Pacifico

Graduate Theses, Dissertations, and Problem Reports

In 2013, the California Bay Area (CBA) passed a set of ordinances to ensure that their 10,000 plus timber soft-story buildings were prepared for seismic events, through nondestructive evaluation methods. Many property owners are searching for an affordable retrofitting system that will also meet CBA’s new laws focusing on installations by the mandated deadlines in 2020. Over the past three to four decades, Fiber Reinforced Polymer (FRP) composites have found their way into the civil infrastructure sector for rehabilitation. The objective of this study is to evaluate the bending behavior retrofitted mortise and tenon timber joints reinforced with engineered wood …


Composites Of Poly(Dimethylsiloxane) And Silica Nanoparticles As An Approach To Manipulating The Conductivity Of Stretchable Gold Films, Brittany Ives Jan 2019

Composites Of Poly(Dimethylsiloxane) And Silica Nanoparticles As An Approach To Manipulating The Conductivity Of Stretchable Gold Films, Brittany Ives

Electronic Theses and Dissertations

Stretchable conductors play a fundamental role in wearable electronics as device electrodes and interconnects. Polydimethylsiloxane (PDMS) is conventionally used as the platform for stretchable conductors which are fabricated by depositing a thin layer of gold metal onto the surface. These gold films fail electrically under minimal strains (15-20% linear elongation) due to uncontrolled crack propagation through the metal film. Adding a rough microstructured polymer layer onto the PDMS surface preserves electrical conductivity in metal films to higher elongations of 60% due to the numerous sites for strain localization. However, such heterogeneous layered systems are vulnerable to delamination, leading to device …


Short Beam Shear Strength Evaluations Of Gfrp Composites: Correlations Through Accelerated And Natural Aging, William Todd Barker Jan 2019

Short Beam Shear Strength Evaluations Of Gfrp Composites: Correlations Through Accelerated And Natural Aging, William Todd Barker

Graduate Theses, Dissertations, and Problem Reports

Fiber Reinforced Polymers (FRP) composites have been materials of interest in replacing or reinforcing steel, wood, and concrete, but lack of understanding of degradation under physical and chemical aging is a main concern. Through many years of research, the understanding of aging or durability of GFRPs has improved. To be able to evaluate aging related degradation rates, an accelerated aging methodology under varying environments is introduced. Accelerated aging is a concept used to age composites in a lab controlled environment under varying pH conditions (2 to 13) and temperatures (~ -20° to +160°F). Once acceleratedly aged testing is completed, Arrhenius …


Freeform Extrusion Fabrication Of Advanced Ceramics And Ceramic-Based Composites, Wenbin Li Jan 2019

Freeform Extrusion Fabrication Of Advanced Ceramics And Ceramic-Based Composites, Wenbin Li

Doctoral Dissertations

"Ceramic On-Demand Extrusion (CODE) is a recently developed freeform extrusion fabrication process for producing dense ceramic components from single and multiple constituents. In this process, aqueous paste of ceramic particles with a very low binder content ( < 1 vol%) is extruded through a moving nozzle to print each layer sequentially. Once one layer is printed, it is surrounded by oil to prevent undesirable water evaporation from the perimeters of the part. The oil level is regulated just below the topmost layer of the part being fabricated. Infrared radiation is then applied to uniformly and partially dry the top layer so that the yield stress of the paste increases to avoid part deformation. By repeating the above steps, the part is printed in a layer-wise fashion, followed by post-processing. Paste extrusion precision of different extrusion mechanisms was compared and analyzed, with an auger extruder determined to be the most suitable paste extruder for the CODE system. A novel fabrication system was developed based on a motion gantry, auger extruders, and peripheral devices. Sample specimens were then produced from 3 mol% yttria stabilized zirconia using this fabrication system, and their properties, including density, flexural strength, Young's modulus, Weibull modulus, fracture toughness, and hardness were measured. The results indicated that superior mechanical properties were achieved by the CODE process among all the additive manufacturing processes. Further development was made on the CODE process to fabricate ceramic components that have external/internal features such as overhangs by using fugitive support material. Finally, ceramic composites with functionally graded materials (FGMs) were fabricated by the CODE process using a dynamic mixing device"--Abstract, page iv.