Engineering Commons^™

Reuse And Recycling Drill Cuttings In Concrete Applications, Maziar Foroutan

LSU Master's Theses

Drill cutting (DC) is a major waste produced during petroleum extraction, which could present a major source of contamination to soil and groundwater, if not disposed of properly. The objective of this study aims to test the hypothesis that drill cuttings can be incorporated as an aggregate in the production of concrete, and is suitable for use in controlled, low-strength material (CLSM) for non-structural applications. To achieve this objective, the physical and consensus properties of drill cuttings were characterized. Concrete mixtures were designed for CLSM applications with and without drill cuttings sampled from two sources. Prepared concrete mixes were then …

Tribological And Dynamical Study Of An Automotive Transmission System, Meng Li

LSU Doctoral Dissertations

The transmission system is critical for automotive and heavy duty equipment due to its prominent role in the powertrain system, which is often challenged with degraded torque capacity and harsh dynamic response. Simulation-guided design can provide appropriate guidelines to resolve these problems with virtual analyses. In current study, the tribological and dynamical study of an automatic transmission is performed at two levels: a wet clutch and powertrain. In this dissertation, tribological study is performed for a wet clutch based on the thermohydrodynamic (THD) analysis that takes the following factors into account. • The groove effect (depth, area, and pattern) is …

Investigation Of Residual Stresses In Melt Infiltrated Sic/Sic Ceramic Matrix Composites Using Raman Spectroscopy, Kaitlin Noelle Kollins

Browse all Theses and Dissertations

Ceramic matric composites (CMCs) are being developed for use in extreme operating conditions. Specifically, there is interest to replace superalloys with Silicon Carbide/Silicon Carbide (SiC/SiC) CMCs in the hot section of gas turbine engines because of their lower densities, high temperature performance, and oxidation resistance. Residual stresses in SiC/SiC CMCs are a direct result of the high temperature processing conditions, a mismatch in the coefficients of thermal expansion between composite constituents, and silicon crystallization expansion upon cooldown. Understanding the residual stress state and magnitudes of these stresses will enable better prediction of behavior and life performance in application environments. This …

Healing Mechanism Investigation Of Self-Healing Concrete By Microencapsulated Calcium Nitrate, Gabriel Andres Arce Amador

LSU Doctoral Dissertations

Durability of reinforced concrete structures depends highly on the integrity of the concrete which protects the structure from the environment. However, concrete is a brittle material and as such it is prone to cracking which allows for detrimental agents to penetrate the structure and produce early deterioration. Embedding microcapsules with chemical healing agents in concrete materials for self-healing applications as well as implementing SMAs as reinforcement of concrete structures for self-closing of cracks are both state-of-the-art techniques with enormous potential for enhancement of concrete infrastructure durability. In this work, both techniques are combined as an alternative for superior self-healing of …

Integration Of Shape-Memory Alloys And Self-Healing Microcapsules To Enhance Concrete Durability, Luis Adolfo Bonilla

LSU Doctoral Dissertations

Self-healing is a term that has not been used for building material until a few decades ago. The concept of developing a material that mimics what living organisms do, such as identify and repair damage, rather than interesting, constitutes a necessity in today’s deteriorated infrastructure. Concrete is one of the main building blocks that support our society’s roads, buildings, and dams. Increasing the service life of such structures will have an important socio-economic benefit in our society. Self-healing methods in concrete have been studied in order to minimize human intervention in maintenance procedures. Previous research in this area has provided …

Organic-Inorganic Graphite And Transition Metal Dichalcogenide Based Composites For 3d Printing, Jorge Alfredo Catalan Gonzalez

Open Access Theses & Dissertations

This project was multipronged to help fuse together topics of additive manufacturing and two-dimensional (2D) layered materials, and studying the mechanical and electrical properties of the composites produced. The composites are made from the thermoplastic polymer acting as a matrix and the graphite and 2D transition metal dichalcogenides (TMDs) serving as the filler or reinforcement. Different concentrations of TMD's were added to the matrix to study the effect of composition on the mechanical and electrical properties. To shed insights into the mechanical properties, test coupons were produced as "dog bone" structures for tensile testing using the ASTM D638 type 5 …

Comprehensive Finite Element Modeling Of Ti-6al-4v Cellular Solids Fabricated By Electron Beam Melting, Edel Arrieta

Open Access Theses & Dissertations

Additive manufacturing permits the fabrication of cellular metals which are materials that can be highly customizable and possess multiple and extraordinary properties such as damage tolerance, metamorphic and auxetic behaviors, and high specific stiffness. This makes them the subject of interest for innovative applications. With interest in these materials for energy absorption applications, this work presents the development of nonlinear finite element models in commercial software platforms (MSC Patran/Nastran) that permit the analysis of the deformation mechanisms of these materials under compressive loads. In the development of these models, a detailed multiscale study on the different factors affecting the response …

Dft Study Of Adsorption Of Trimetallic Endohedral Fullerenes On Graphene, Nakul Nitin Karle

Open Access Theses & Dissertations

A density functional theory (DFT) study on the geometric and electronic structure of C60 and Sc3N@C80 along with their adsorption on pristine single layer graphene (SLG) is presented. C60 is found to adsorb in two nearly degenerate configurations: (i) with a pentagon facing the SLG, which is the most stable one, and (ii) with a hexagon facing the SLG in a face-to-face perfect alignment, rarely common in Ï?â??Ï? interactions, 0.06 eV higher in energy. The calculated binding energy of 0.76 eV, which includes dispersion effects, is in good agreement with previous theoretical and experimental reports. On the contrary, Sc3N@C80 adsorption …

Structural And Mechanical Characterization Of Nanocrystalline Tungsten And Tungsten-Based Alloy Thin Films For Extreme Environment Applications, Gustavo Martinez

Open Access Theses & Dissertations

Extreme environments associated with nuclear applications often results in degradation of the physical, mechanical and thermo-mechanical properties of the materials. Tungsten (W) exhibits unique physical and mechanical properties, which makes tungsten a good candidate for nuclear applications; however, intrinsic W exhibits low fracture toughness at all temperatures in addition to a high ductile to brittle transition. In the present work, nanocrystalline W, W-Y and W-Mo alloys were nanoengineered for nuclear applications. Nanocrystalline tungsten coatings with a thickness of ~1 µm were deposited onto Silicon (100) and Sapphire (C-plane) using RF and DC sputtering techniques under various growth conditions. Yttrium content …

Process-Structure-Property Relationship In Magnesium-Based Biodegradable Alloy For Biomedical Applications, Pramanshu Trivedi

Open Access Theses & Dissertations

Magnesium alloys are considered to be the next generation of biomaterials because of their ability to degrade in the physiological environment. We elucidate here the impact of multiaxial forging of Mg-2Zn-2Gd alloy on grain refinement to sub-micron regime and relate the structure to mechanical properties and biological functionality. As-cast and annealed samples were multiaxial forged (MAF) for a total number of two passes with a true strain of ~2/pass. Considering that the microstructure governs the biological response of materials, we studied the constituents of the microstructure in conjunction with the mechanical behavior. The antimicrobial behavior in a Mg-2Zn-2Gd alloy with …

Frontal Crash Analysis Of A Conformable Cng Tank Using Finite Element Analysis, Datta Sandesh Manjunath

Dissertations, Master's Theses and Master's Reports

The purpose of this study is to computationally model and analyze a Conformable Compressed Natural Gas (CNG) fuel tank for frontal crashes using Finite Element Analysis. Researchers have developed a CNG fuel tank, which is conformable, non-conventional and non-cylindrical. This tank increases cost efficiency, volumetric efficiency and cargo efficiency in CNG vehicle applications. A lightweight pickup truck (2015 Chevrolet Silverado) has been used to integrate the CNG tanks and field-testing has been conducted to demonstrate the application.

The report mainly focuses on the effective finite element modeling of the chassis, brackets and tanks using HYPERMESH and RADIOSS. The frontal crash …

Seaweed To Sealant : Multifunctional Polysaccharides For Regenerative Medicine And Drug Delivery Applications, Spencer Lincoln Fenn

Graduate College Dissertations and Theses

Pneumothorax, or a collapsed lung, is a serious medical condition resulting when air or fluid escapes the lung into the chest cavity and prevents the lung from inflating. Few viable means of sealing the damaged and leaking tissues are currently available, leading to longer hospital stays, multiple interventions, and increasing costs of care. The motivation of this dissertation is to engineer a novel polysaccharide-based therapeutic surgical sealant, which can be utilized to seal trauma-induced damage to the outer lining of the lung, i.e. pleura, preventing or reversing lung collapse to restore normal breathing function.

The use of polysaccharides, such as …

Fabrication And Thermoelectric Characterization Of Stretchable Conductive Latex-Based Composites, Cory Michael Arcovitch

Graduate College Dissertations and Theses

Miniaturized stretchable electronic devices that can be bent and strained elastically without breaking, have drawn considerable research interest in recent years for wearable computers and integrated bio-sensor applications. Portable electrical power harvesting remains a critical challenge in flexible electronics materials. One proposed solution has been to convert waste heat from the human body into electricity using thermoelectric materials. Traditionally, however, these materials are brittle ceramic semiconductors with limited fracture resistance under deformation. The primary objective of this thesis is to address this challenge by fabricating and studying the mechanical, thermal and electrical performance of stretchable composites combining natural latex polymer …

Computational Studies On Fluid And Particle Dynamics, Chenguang Zhang

LSU Doctoral Dissertations

This dissertation is divided into two parts. The first part includes chapter 2 to 4, which focus on development and application of numerical algorithm on particle and fluid simulation. Starting with a pure granular system in a driven cavity setup (Chapter 2), we move on to the immersed boundary simulation of fluid solid interaction (Chapter 3). This part ends with a coupled immersed boundary-discrete particle implementation. The second part includes Chapter 5 and Appendix A, each deals with an independent problem and focuses more on the theoretical aspects. Chapter 5 deals with a classic fluid dynamics problem of thermal wave …

Printed Dot Quality In Response To Doctor Blade Angle, Bilge N. Altay, Alexandra Pekarovicova, Paul D. Fleming

Bilge Nazli Altay