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Nondestructive Evaluation And Structural Health Monitoring Of Manufacturing Flaws And Operational Damage In Composite Structures, Robin James

Theses and Dissertations

Advanced composite materials have begun to be used extensively in the manufacturing of aerospace structures. Composite aerospace structures can develop complex types of damages during the manufacturing stages and operational lifetime. This creates an indispensable demand for appropriate nondestructive evaluation (NDE) and structural health monitoring (SHM) methods that are tailored to specific types of damage. This dissertation addresses innovative methods for NDE and SHM of manufacturing flaws and operational damage in composite structures.

For the NDE of manufacturing flaws in carbon fiber reinforced polymer (CFRP) composites, an eddy current testing (ECT) NDE method has been developed by conducting multiphysics modeling …

Detection Of Delaminations In Carbon Fiber Reinforced Polymers Embedded With Terfenol-D Particles Using Machine Learning, Christopher Nelon

All Theses

The characterization of the damage state of a system provides insight into its performance and safety during operation. In composite materials, specifically, fiber-reinforced polymers, delaminations form from the evolution of cracks in a matrix that leads to adhesion failure between adjacent laminae. Nondestructive evaluation (NDE) seeks to characterize the state of a material or system during non-operational times. A previously proposed NDE method employs embedded magnetostrictive particles between laminae of carbon fiber reinforced polymer (CFRP) for damage sensing. The phenomenon of magnetostriction couples the mechanical state of a material with its magnetic state so that a change in the local …

Nondestructive Evaluation Of Solid Cargo Inside Cylindrical Containers By Using Linear And Nonlinear Acoustic Resonance Spectroscopy, Kevin Yi-Wei Lin

Electronic Theses and Dissertations

The Nondestructive Evaluation (NDE) of cylindrical containers is of critical importance because of their ubiquity in industrial applications. However, there is a paucity of research in the literature on NDE studies of solid cargo inside cylindrical containers. This dissertation consists of three connected projects investigating the application of linear and nonlinear Acoustic Resonance Spectroscopy (ARS) to the NDE of solid cargo inside sealed cylindrical containers. In these projects, the container of interest varied from extremely complicated to very simplified, and the studies extended from applied to basic physics problems. The first study was focused on an empty Transnuclear-32 (TN-32) nuclear …

Physics-Based Approaches For Structural Health Monitoring And Nondestructive Evaluation With Ultrasonic Guided Waves, Md Yeasin Bhuiyan

Theses and Dissertations

The engineering infrastructures have a growing demand for damage monitoring systems to avoid any potential risk of failure. Proper damage monitoring solutions are of a great interest to this growing demand. The structural health monitoring (SHM) and nondestructive evaluation (NDE) offer appropriate online and offline damage monitoring solutions for a variety of mechanical and civil infrastructures that includes unmanned aerial vehicles (UAV), spaceships, commercial aircraft, ground transportation, wind turbines, nuclear spent fuel storage tanks, bridges, naval ships, and submarines. The fundamentals of the ultrasonic SHM and NDE consist of multi-disciplinary fields. The dissertation addresses SHM and NDE using ultrasonic guided …

Phase I Inspection Of The Stay Cable System On The Us 231 William H. Natcher Bridge Over The Ohio River, Theodore Hopwood Ii, Sudhir Palle, Danny Wells, Bobby W. Meade, Jared Fairchild, Christopher Goff

Kentucky Transportation Center Research Report

The US 231 Natcher Bridge was opened in 2002. By 2006 cracking was observed in the plastic piping that protected the stay cable strands from the environment at both the deck and tower anchorages. Over time the extent of cracking increased and an investigation was initiated to assess the types of deterioration impacting the cables, their causes and their impacts on the integrity of the stay cables.

From 2012-2015, a series of in-depth field inspections were performed using visual and nondestructive testing. Most of this work focused on the piping at the deck anchorages. The inspections disclosed voids in cable …

Modern Statistical Methods And Uncertainty Quantification For Evaluating Reliability Of Nondestructive Evaluation Systems, Jeremy Scott Knopp

Browse all Theses and Dissertations

The reliability of Nondestructive Evaluation (NDE) is an important input for risk analysis for sustainment of aging infrastructure. Reliability has typically been quantified via probability of detection (POD) studies. There are three problems with POD modeling methodologies provided in the most recent guidance on the subject:

1) Current models do not estimate the extremes of a POD curve very well because of the assumption that the POD curve approaches zero as flaw size goes to zero, and the POD curve approaches one as the flaw size goes to infinity.

2) The existing 2-parameter logit/probit models can be misused since there …

Develop Sonic Infrared Imaging Nde For Local Damage Assessment In Civil Structures, Qi He

Wayne State University Dissertations

Nondestructive Evaluation (NDE) is an interdisciplinary field of study, which is concerned with the development of analysis techniques and measurement technologies for the quantitative characterization of materials, tissues and structures. Ultrasonic IR Imaging is a novel NDE technique, which combines a short ultrasonic pulse excitation and infrared imaging to detect defects in materials and structures. In this technique, a sound pulse with a frequency in the range of 20-40kHz is infused on a target material for a short duration (usually less than one second). The sonic/ultrasonic sound waves travel into the material and cause rubbing and clapping between the surfaces …

Fusion Of Microwave And Eddy Current Data For A Multi-Modal Approach In Evaluating Corrosion Under Paint And In Lap Joints, Kapil Gupta, Mohammad Tayeb Ahmad Ghasr, Sergey Kharkovsky, R. Zoughi, R. Joe Stanley, Ajay Padwal, Matthew O'Keefe, Donald D. Palmer, J. Blackshire, Gary Steffes, N. Wood

Electrical and Computer Engineering Faculty Research & Creative Works

Critical aircraft structures are susceptible to hidden corrosion. Find-it and fix-it approaches are inefficient as it relates to managing the problems associated with corrosion. More comprehensive corrosion information may be obtained using data fusion from several detection and evaluation methods. To this end, microwave, conventional and pulsed eddy current data from a multi-layer corroded panel, representing an aircraft lap joint, are fused and used as inputs to a structural analysis model to obtain a comprehensive snapshot of the corroded environment. This paper presents the data fusion algorithm and the structural analysis model along with a discussion of the results.

Pattern Recognition For Nondestructive Evaluation, S. Morris, P. O'Rorke, William E. Bond, M. M. Amirfathi, Daniel C. St. Clair

Computer Science Faculty Research & Creative Works

The issues involved in automating nondestructive evaluation (NDE) techniques are outlined. Attention is given to research focused on the application of machine learning techniques to the construction and maintenance of knowledge-based systems which are capable of evaluating the readings from nondestructive tests that have been performed on aircraft components. Preliminary results obtained from this research are described. In particular, the authors discuss the application of a symbolic machine learning algorithm, ID3, to the NDE problem. ID3 has been used by Douglas Aircraft to classify defects in sets of standard NDE reference blocks. Based on the preliminary results, a need for …

Periodic Nondestructive Evaluation Of In-Service Metal Bridges, Theodore Hopwood Ii, Robert C. Deen

Kentucky Transportation Center Research Report

Metal bridges are subject to in-service fracture problems mainly caused by fatigue. This report considers the prevention of bridge failure by the performance of periodic nondestructive evaluations. Differences in visual and other nondestructive inspect ions are discussed. The use of preliminary inspection strategies for proper testing also is presented. The suitability of common types of nondestructive testing for bridge inspections also are included.