Download or read book Residual Damage Analysis written by Burl Edward Dishongh and published by . This book was released on 1990 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Residual Strength of Stiffened Panels with Multiple Site Damage written by M. F. J. Koolloos and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book DLTS Analysis of Residual Damage in Low dose Ion implanted Silicon written by and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Progressive Damage Methodology for Residual Strength Predictions of Notched Composite Panels written by Timothy W. Coats and published by . This book was released on 1998 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Progressive Damage Methodology for Residual Strength Predictions of Center Crack Tension Composite Panels written by Timothy William Coats and published by . This book was released on 1996 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact Damage Resistance and Residual Property Assessment of 0 45 90 S Scs 6 Timetal 21s written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-05 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impact damage resistance and residual mechanical properties of (0/ +/- 45/90)s SCS-6/Timetal 21S composites were evaluated. Both quasi-static indentation and drop-weight impact tests were used to investigate the impact behavior at two nominal energy levels (5.5 and 8.4 J) and determine the onset of internal damage. Through x-ray inspection, the extent of internal damage was characterized non-destructively. The composite strength and constant amplitude fatigue response were evaluated to assess the effects of the sustained damage. Scanning electron microscopy was used to characterize internal damage from impact in comparison to damage that occurs during mechanical loading alone. The effect of stacking sequence was examined by using specimens with the long dimension of the specimen both parallel (longitudinal) and perpendicular (transverse) to the 0 deg fiber direction. Damage in the form of longitudinal and transverse cracking occurred in all longitudinal specimens tested at energies greater than 6.3 J. Similar results occurred in the transverse specimens tested above 5.4 J. Initial load drop, characteristic of the onset of damage, occurred on average at 6.3 J in longitudinal specimens and at 5.0 J in transverse specimens. X-ray analysis showed broken fibers in the impacted region in specimens tested at the higher impact energies. At low impact energies, visible matrix cracking may occur, but broken fibers may not. Matrix cracking was noted along fiber swims and it appeared to depend on the surface quality of composite. At low impact energies, little damage has been incurred by the composite and the residual strength and residual life is not greatly reduced as compared to an undamaged composite. At higher impact energies, more damage occurred and a greater effect of the impact damage was observed. Miller, Jennifer L. and Portanova, Marc A. and Johnson, W. Steven Langley Research Center RTOP 505-63-50-04...
Download or read book Loss and Damage from Climate Change written by Reinhard Mechler and published by Springer. This book was released on 2018-11-28 with total page 563 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an authoritative insight on the Loss and Damage discourse by highlighting state-of-the-art research and policy linked to this discourse and articulating its multiple concepts, principles and methods. Written by leading researchers and practitioners, it identifies practical and evidence-based policy options to inform the discourse and climate negotiations. With climate-related risks on the rise and impacts being felt around the globe has come the recognition that climate mitigation and adaptation may not be enough to manage the effects from anthropogenic climate change. This recognition led to the creation of the Warsaw International Mechanism on Loss and Damage in 2013, a climate policy mechanism dedicated to dealing with climate-related effects in highly vulnerable countries that face severe constraints and limits to adaptation. Endorsed in 2015 by the Paris Agreement and effectively considered a third pillar of international climate policy, debate and research on Loss and Damage continues to gain enormous traction. Yet, concepts, methods and tools as well as directions for policy and implementation have remained contested and vague. Suitable for researchers, policy-advisors, practitioners and the interested public, the book furthermore: • discusses the political, legal, economic and institutional dimensions of the issue• highlights normative questions central to the discourse • provides a focus on climate risks and climate risk management. • presents salient case studies from around the world.
Download or read book Cumulative Damage Analysis in Structural Fatigue written by LF. Impellizzeri and published by . This book was released on 1970 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of residual stress on fatigue is studied using electron microscopy on fracture surfaces of specimens tested under spectrum loading. The level of residual stress that exists at the point of stress concentration is shown to be one of the parameters affecting striation spacing. A review of numerous variable amplitude test results generated by government agencies and aerospace companies further suggests that a straightforward technique quantitatively defining the effect of continually changing residual stress patterns should provide a reliable tool for predicting cumulative damage in fatigue. The two major difficulties relating to the utilization of residual stress considerations in a cumulative damage rule are: (a) determining the level of residual stress existing at the notch root; and (b) computing its effect on N, cycles to failure. A cumulative damage rule including the developments in (a) and (b) above is presented. Essentially, the rule involves the use of conventional ?n/N computations, except the selection of a value for N is affected by the levels and variations of residual stress existing at a discontinuity. Loading parameters that affect fatigue-life predictions using the cumulative damage rule include peak load level, load ratio, block size, and load-level sequence. Typical laboratory spectrum-test results that are investigated include the NASA gust spectrum. Specimens tested to this spectrum sustained 9 blocks to failure in a low-high sequence, 26 blocks in a high-low sequence, and 20 blocks in a high-low-high-sequence. Corresponding life predictions are 10.9, 25.2, and 19.6 blocks to failure.
Download or read book Advanced Durability and Damage Tolerance Design and Analysis Methods for Composite Structures Lessons Learned from NASA Technology Development Programs written by Charles E. Harris and published by . This book was released on 2003 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Residual Stress Analysis Around Foreign Object Damage Using Synchrotron Diffraction written by P. Frankel and published by . This book was released on 2006 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis Methods for Progressive Damage of Composite Structures written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-22 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document provides an overview of recent accomplishments and lessons learned in the development of general progressive damage analysis methods for predicting the residual strength and life of composite structures. These developments are described within their State-of-the-Art (SoA) context and the associated technology barriers. The emphasis of the authors is on developing these analysis tools for application at the structural level. Hence, modeling of damage progression is undertaken at the mesoscale, where the plies of a laminate are represented as a homogenous orthotropic continuum. The aim of the present effort is establish the ranges of validity of available models, to identify technology barriers, and to establish the foundations of the future investigation efforts. Such are the necessary steps towards accurate and robust simulations that can replace some of the expensive and time-consuming "building block" tests that are currently required for the design and certification of aerospace structures. Rose, Cheryl A. and Davila, Carlos G. and Leone, Frank A. Langley Research Center COMPOSITE STRUCTURES; AIRCRAFT STRUCTURES; DAMAGE ASSESSMENT; RESIDUAL STRENGTH; STRUCTURAL ANALYSIS; MATHEMATICAL MODELS; LESSONS LEARNED; MESOSCALE PHENOMENA; LAMINATES; CONTINUUMS; PREDICTIONS
Download or read book A Progressive Damage Model and Analysis Methodology for Predicting the Residual Strength of Composite Laminates written by CE. Harris and published by . This book was released on 2006 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The durability and damage tolerance of laminated composites are critical design considerations for airframe composite structures. Therefore, the ability to model damage initiation and growth and predict the life of laminated composites is necessary to achieve efficient and economical structural designs. The purpose of the research presented in this paper is to experimentally verify the application of the damage model developed by the authors to predict progressive damage development in a toughened material system. Damage growth, stiffness degradation, and residual strength were experimentally determined for cross-ply and quasi-isotropic IM7/5260 graphite/bismaleimide laminates due to monotonic and tension-tension fatigue. The damage model, which has been implemented into a finite element code, was used to predict the stiffness loss and residual strength of unnotched and notched laminates. The model predictions were in good agreement to experimental results for several different fatigue loading histories and several different laminate stacking sequences.
Download or read book A Progressive Damage Methodology for Residual Strength Predictions of Notched Composite Panels written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-28 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The translaminate fracture behavior of carbon/epoxy structural laminates with through-penetration notches was investigated to develop a residual strength prediction methodology for composite structures. An experimental characterization of several composite materials systems revealed a fracture resistance behavior that was very similar to the R-curve behavior exhibited by ductile metals. Fractographic examinations led to the postulate that the damage growth resistance was primarily due to fractured fibers in the principal load-carrying plies being bridged by intact fibers of the adjacent plies. The load transfer associated with this bridging mechanism suggests that a progressive damage analysis methodology will be appropriate for predicting the residual strength of laminates with through-penetration notches. A progressive damage methodology developed by the authors was used to predict the initiation and growth of matrix cracks and fiber fracture. Most of the residual strength predictions for different panel widths, notch lengths, and material systems were within about 10% of the experimental failure loads. Coats, Timothy W. and Harris, Charles E. Langley Research Center RTOP 538-13-11-05...
Download or read book Analysis of Residual Strength of Flat and Curved Panels with and Without Stiffeners with Multiple site Damage written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact Damage Resistance and Residual Property Assessment of 0 45 90 s SCS 6 Timetal 21S written by and published by . This book was released on 1995 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SSC written by United States. Ship Structure Committee and published by . This book was released on 1997 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book USAF Damage Tolerant Design Handbook written by and published by . This book was released on 1984 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:
