Author: John Vieira Publisher: ISBN: Category : Feasibility studies Languages : en Pages : 55
Book Description
The feasibility of using photoelasticity and moire methods to obtain dynamic three-dimensional stress distributions was investigated. The photoelasticity methods considered include scattered light techniques, embedded polariscopes, and embedded photoelastic layers in optically insensitive materials. During the course of the program the physical and optical properties of a number of model materials were determined, the effect of stress upon Polaroid materials was established, and several preliminary model studies were conducted using impact loadings. As a result of these experiments, the embedded polariscope technique has been selected as the most suitable method for immediate application to dynamic three-dimensional problems. The instrumentation and calibration procedures required for studies of this type are discussed. (Author).
Author: W. F. Riley Publisher: ISBN: Category : Languages : en Pages : 55
Book Description
In this research program the feasibility of using photoelasticity and moire methods to obtain dynamic three-dimensional stress distributions was investigated. The photoelasticity methods considered include scattered light techniques, embedded polariscopes, and embedded photoelastic layers to optically insensitive materials. During the course of the program the physical and optical properties of a number of model materials were determined, the effect of stress upon Polaroid materials was established, and several preliminary model studies were conducted using impact loadings. As a result of these experiments, the embedded polariscope technique has been selected as the most suitable method for immediate application to dynamic three-dimensional problems. The instrumentation and calibration procedures required for studies of this type are discussed.
Author: Kirtland Air Force Base (N.M.). Air Force Weapons Laboratory Publisher: ISBN: Category : Atomic bomb Languages : en Pages : 400
Book Description
This report contains summaries of all research reports dealing with nuclear weapons effects on hardened structures, published under Project 1080 by the AFWL Structures Branch (formerly the AFSWC Structures Division) and predecessor organizations from July 1951 to February 1964. Section I contains edited abstracts of unnumbered reports, technical memoranda, technical notes, technical reports, and technical documentary reports. Section II lists all reports by document number (unnumbered reports are listed chronologically); Section III lists reports by subject area; and Section IV lists reports by contractor.
Author: Publisher: ISBN: Category : Aeronautics Languages : en Pages : 1028
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Author: M. M. Leven Publisher: Elsevier ISBN: 1483158543 Category : Technology & Engineering Languages : en Pages : 494
Book Description
Photoelasticity presents the development of photoelasticity. This book discusses the principle of optical equivalence of stressed isotropic bodies. Organized into 29 chapters, this book begins with an overview of the progress in three-dimensional photoelasticity. This text then summarizes the approximate theoretical analysis by the strain-energy technique and derives the basic equations for the evaluation of P and Q by graphical integration. Other chapters consider the importance of stress concentrations in the domain of strength of materials, particularly where fatigue is present. This book discusses a well the various instructive fractures and indicates that the strength of bakelite is determined by the maximum tensile stresses as computed by advanced methods of stress analysis. The final chapter deals with the two fundamental problems in three-dimensional photoplasticity and explains the general stress-optic law under plastic flow without unloading. This book is a valuable resource for designers as well as mechanical and civil engineers.
Author: Louis Jean Thompson Publisher: ISBN: Category : Artificial satellites Languages : en Pages : 70
Book Description
The Aerospace Nuclear Safety Program at Sandia Corporation requires an independent assessment of the safety of all nuclear power supplies used in aerospace under all conditions from factory shipment through re-entry from space. The effects of impact against any point on the earth by a nuclear power supply or its components must be evaluated as part of this assessment. This report: (1) evluates the fundamental mechanisms involved in soil impacts by cylindrical projectiles with velocities of 500-700 feet per second; (2) defines the problem of specifying impact targets which closely simulate various portions of the earth's surface; and (3) describes an analytical and experimental program intended to obtain the information needed to properly specify a simulated earth target for use in Aerospace Nuclear Safety impact tests.
Author: John H. Hubbard Publisher: ISBN: Category : Photomechanical processes Languages : en Pages : 77
Book Description
The report presents the results of a study into the experimental techniques of full field representation applicable to stress analysis in three dimensions. The simple case of the distribution of stress on the boundary of a circular discontinuity in an elastic half space was examined from the viewpoint of existing theory and verified by model analysis employing eight experimental approaches. Two models were two dimensional in nature and provided an experimental standard for the other models as well as a demonstration of the flexibility of experimental stress analysis. The most accurate representation of stress distribution for the three dimensional models were the Frozen Stress and Scatterred Light models. Less accurate representations were obtained with the Composite, Embedded Polariscope and Embedded Moire Models. Finally, the feasibility was investigated of applying the techniques of Holography to photoelastic model. Each of these approaches is discussed in detail, and the advantages and disadvantages of each critically examined. (Author).
Author: R. Weller Publisher: ISBN: Category : Photoelasticity Languages : en Pages : 42
Book Description
A method has been developed for making photoelastic analyses of three-dmensional stress systems by utilizing the polarization phenomena associated with the scattering of light. By this method, the maximum shear and the directions of the three principal stresses at any point within a model can be determined, and the two principal stresses at a free-bounding surface can be seaparately evaluated. Polarizing light is projected into the model through a slit so that it illuminates a plane section. The light is continuously analyzed along its path by scattering and the state of stress in the illuminated section is obtained. By means of a series of such sections, the entire stress field may be explored. The method was used to analyze the stress system of a simple beam in bending. The results were found to be in good agreement with those expected from elementary theory.
Author: John Vieira
Author: W. F. Riley
Author: Kirtland Air Force Base (N.M.). Air Force Weapons Laboratory
Author: 
Author: Defense Documentation Center (U.S.)
Author: 
Author: M. M. Leven
Author: Louis Jean Thompson
Author: John H. Hubbard
Author: R. Weller