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A nonlinear theory of bending and buckling of thin elastic shallow spherical shells

Description: The problem of the finite displacement and buckling, of a shallow spherical dome is investigated both theoretically and experimentally. Experimental results seem to indicate that the classical criterion of buckling is applicable to very shallow spherical domes for which the theoretical calculation was made. A transition to energy criterion for higher domes is also indicated.
Date: August 1954
Creator: Kaplan, A. & Fung, Y. C.
Partner: UNT Libraries Government Documents Department

Buckling tests on eccentrically loaded beam columns

Description: Formulas are obtained for computing the buckling load of rods eccentrically loaded at each end, the computation being extended in particular to the inelastic range. The test results are graphically presented on three sets of curves. Two of these, at least for the elastic range, are independent of the material tested. The third set, which is independent of the material, possesses greater clearness and is therefore used for comparing the test results with the theoretical.
Date: October 1941
Creator: Cassens, J.
Partner: UNT Libraries Government Documents Department

The effect of dynamic loading on the strength of an inelastic column

Description: From Summary: "The maximum loads of idealized inelastic H-section columns whose pinned ends approach each other at a constant rate are presented. The solutions indicate that as the rate of end displacement becomes smaller, the dynamic buckling solutions approach the static solution as a lower limit. The effects of inertia forces are apparently negligible at rates of end displacement comparable to those normally used in static column tests."
Date: March 1954
Creator: Brooks, William A., Jr. & Wilder, Thomas W., III
Partner: UNT Libraries Government Documents Department

Critical combinations of bending, shear, and transverse compressive stresses for buckling of infinitely long flat plates

Description: From Summary: "Three-dimensional interaction surfaces are presented for the computation of elastic buckling stresses for an infinitely long flat plate subjected to combinations of bending, shear, and transverse compression in its plane - a loading approximating that occurring in a shear web. Surfaces are presented for two sets of edge conditions: both edges simply supported and lower edge simply supported, upper edge clamped. Present results are in good agreement with data for one-load and two-load limiting cases previously published."
Date: December 1951
Creator: Johnson, Aldie E., Jr. & Buchert, Kenneth P.
Partner: UNT Libraries Government Documents Department

Principles of moment distribution applied to stability of structures composed of bars or plates

Description: The principles of the cross method of moment distribution, which have previously been applied to the stability of structures composed of bars under axial load, are applied to the stability of structures composed of long plates under longitudinal load. A brief theoretical treatment of the subject, as applied to structures composed of either bars or plates, is included, together with an illustrative example for each of these two types of structure. An appendix presents the derivation of the formulas for the various stiffnesses and carry-over factors used in solving problems in the stability of structures composed of long plates.
Date: 1945
Creator: Lundquist, Eugene E.; Stowell, Elbridge Z. & Schuette, Evan H.
Partner: UNT Libraries Government Documents Department

An Investigation of the Instantaneous and Creep Buckling of Initially Out-of-Round Tubes Subjected to External Pressure

Description: Report regarding a method for predicting the instantaneous and creep buckling characteristics of tubes to lateral external pressures using a small sample of 8.0-in.-o.d. stainless steel tubes. The report includes the development and application of buckling theories. Appendix begins on page 71.
Date: 1963
Creator: Corum, J. M.
Partner: UNT Libraries Government Documents Department

Some design implications of the effects of aerodynamic heating

Description: Report presenting an examination of creep and thermal buckling in order to determine their effect on the design of structures for high-speed aircraft. Consideration is given to the use of insulation as a means of alleviating the effect of aerodynamic heating. Creep did not appear to be a significant factor, but thermal buckling may have a substantial effect on the structural design.
Date: July 28, 1955
Creator: Heldenfels, Richard R.
Partner: UNT Libraries Government Documents Department

Elastic buckling under combined stresses of flat plates with integral waffle-like stiffening

Description: Theory and experiment were compared and found in good agreement for the elastic buckling under combined stresses of long flat plates with integral waffle-like stiffening in a variety of configurations. For such flat plates, 45 degree waffle stiffening was found to be the most effective of the configurations for the proportions considered over the widest range of combinations of compression and shear.
Date: January 1954
Creator: Dow, Norris F.; Levin, L. Ross & Troutman, John L.
Partner: UNT Libraries Government Documents Department

Charts relating the compressive buckling stress of longitudinally supported plates to the effective deflectional and rotational stiffness of the supports

Description: Report presenting a stability analysis of a long flat rectangular plate subjected to uniform longitudinal compressive stress and support along its longitudinal edges and one or more other longitudinal lines by elastic line supports. This was performed in order to provide more information about stabilization methods for thin-wing construction. The effective stiffness of different supports and the buckling observed in different structures is provided.
Date: August 1953
Creator: Anderson, Roger A. & Semonian, Joseph W.
Partner: UNT Libraries Government Documents Department

Charts relating the compressive buckling stress of longitudinally supported plates to the effective deflectional and rotational stiffness of the supports

Description: A stability analysis is made of a long flat rectangular plate subjected to a uniform longitudinal compressive stress and supported along its longitudinal edges and along one or more longitudinal lines by elastic line supports. The elastic supports possess deflectional and rotational stiffness. Such configuration is an idealization of the compression cover skin and internal structure of a wing and tail surfaces. The results of the analysis are presented in the form of charts in which the buckling-stress coefficient is plotted against the buckle length of the plate for a wide range of support stiffnesses. The charts make possible the determination of the compressive buckling stress of plates supported by members whose stiffness may or may not be defined by elementary beam bending and twisting theory but yet whose effective restraint is amenable to evaluation. The deflectional and rotational stiffness provided by longitudinal stiffeners and full-depth webs is discussed and numerical examples are given to illustrate the application of the charts to the design of wing structures.
Date: 1954
Creator: Anderson, Roger A. & Semonian, Joseph W.
Partner: UNT Libraries Government Documents Department

Material Bucklings of Critical and Subcritical Uranium Carbide Fueled Graphite Assemblies: Part 1, Experiment

Description: Introduction: A series of critical and subcritical experiments have been carried out as part of the Advanced Sodium Graphite Reactor (ASGR) Critical Experiments program to provide physics information which would be directly applicable to the AGSR concept.
Date: December 1, 1964
Creator: Hillig, O. R. & Latham, D. W.
Partner: UNT Libraries Government Documents Department

A REMARK ON THE SECOND FUNDAMENTAL THEOREM IN ONE-VELOCITY TRANSPORT THEORY

Description: In one-velocity transport theory with linearly anisotropic scattering, the second fundamental theorem always gives an under-estimate of the average nonescape probability of neutrons from critical slabs, spheres, and cylinders if the buckling is calculated with zero extrapolation length. (auth)
Date: October 31, 1962
Creator: Dresner, L.
Partner: UNT Libraries Government Documents Department

Correlation of creep-buckling tests with theory

Description: Report presenting the results of short-time creep-buckling and creep-bending tests of 2024-T4 aluminum-alloy columns of slenderness ratio 111 are presented. Tests were performed at 600 degrees Fahrenheit and strain measurements were taken with high-temperature electric-resistance strain gages.
Date: May 23, 1956
Creator: Patel, Sharad A.; Kempner, Joseph; Erickson, Burton & Mobassery, Abol H.
Partner: UNT Libraries Government Documents Department

Buckling of a Thin Initially Wrinkled Rectangular Plate

Description: The deformation of a thin elastic plate which is initially wrinkled when the plate is subjected to a constant compressive end thrust is considered. The singularly perturbed bifurcation theory of Reiss and Matkowsky is used. It is found that the initial deformation (imperfection) of the plate leads to solutions which explain the experimentally observed decrease in the buckling load from that predicted by bifurcation theory and the smooth transition to a buckled solution.
Date: August 1981
Creator: Matkowsky, Bernard J.; Putnick, Leonard J. & Reiss, Edward L.
Partner: UNT Libraries Government Documents Department

An investigation of the effects of rapid skin heating on box beams loaded in bending

Description: Report presenting testing of two beams of three web types which were loading in bending and subjected to rapid skin heating at rates from about 50 to 70 degrees Fahrenheit per second. The investigation was meant to determine some of the effects that rapid skin heating would have on the buckling and failing strength of multiweb-wing structures. The three types of web tested included the channel web, corrugated web, and truss web.
Date: March 23, 1955
Creator: Pride, Richard A.
Partner: UNT Libraries Government Documents Department

Charts giving critical compressive stress of continuous flat sheet divided into parallelogram-shaped panels

Description: From Summary: "Charts giving the compressive-buckling stress coefficients for sheet panels of a shape occurring in swept-wing plan forms are presented. The panels are assumed to be a part of a continuous flat sheet divided by nondeflecting supports into parallelogram-shaped areas. The stability analysis was performed by the energy method and the results show that, over a wide range of panel aspect ratio, such panels are decidedly more stable than equivalent rectangular panels of the same area."
Date: July 1951
Creator: Anderson, Roger A.
Partner: UNT Libraries Government Documents Department

Residual stress mapping by micro X-ray diffraction: Application to the study of thin film buckling

Description: Thin films deposited by Physical Vapour Deposition techniques on substrates generally exhibit large residual stresses which may be responsible of spontaneous detachment of the film from its substrate and in the case of compressive stresses, thin film buckling. Although these effects are undesirable for future applications, one may take benefit of it for thin film mechanical properties investigation. Since the 80's, a lot of theoretical works have been done to develop mechanical models with the aim to get a better understanding of driven mechanisms giving rise to this phenomenon and thus to propose solutions to avoid such problems. Nevertheless, only a few experimental works have been done on this subject to support these theoretical results and nothing concerning local stress/strain measurement mainly because of the small dimension of the buckling (few tenth mm). This paper deals with the application of micro beam x-ray diffraction available on synchrotron radiation sources for stress/ strain mapping analysis of gold thin film buckling.
Date: November 6, 2002
Creator: Goudeau, P.; Villain, P.; Tamura, N.; Celestre, R.S. & Padmore, H.A.
Partner: UNT Libraries Government Documents Department

Dynamic plastic buckling of spherical shells during collapse

Description: Conditions are established that lead to the growth of initial displacement imperfections (buckling) of complete spherical shells during significant inward motion. This preliminary study is limited to axisymmetric buckling modes only. Shell thickening during inward motion is taken into account, and its effect is found to be important for the stability and maximum growth of a given initial imperfection mode. Upper and lower bounds on the initial, uniform impulsive velocity loading are found (in terms of spherical shell geometry and material parameters) such that growth of initial displacement imperfections remains less than a prescribed multiplier when initial inward velocity lies outside the bounded region. 10 refs., 8 figs.
Date: January 1, 1989
Creator: Duffey, T.A.
Partner: UNT Libraries Government Documents Department

BAND-1--A DATA REDUCTION PROGRAM FOR THE IBM-704

Description: BAND-1 is an IBM-704 program to reduce the experimental data obtained from measurements of the neutron activation distribution within a critical facility. The data reduction consists of correcting the measured data, sorting and ordering it, and calculating the critical buckling parameters by means of a least squares analysis. (auth)
Date: May 1, 1961
Creator: Anderson, B.L.; Hemphill, A.P.; Jarvis, P.H. & Kettler, R.E.
Partner: UNT Libraries Government Documents Department

Direct Strength Method for Web Crippling of Cold-formed Steel C and Z Sections Subjected to Interior One Flange Loading and End One Flange Loading

Description: The main objective of this research is to extend the “Direct strength method” for determining the web crippling strength of cold-formed steel C and Z sections subjected to End one flange loading and Interior one flange loading conditions. Direct strength method is applied for designing the columns and beams earlier. The existing specifications equation for calculating the web crippling strength of cold-formed steels designed by American Institute of Iron and Steel is very old method and it is based on the extensive experimental investigations conducted at different universities. Calculating the web crippling strength of cold-formed steels using direct strength method is a new technique. In the present research the web crippling strength of cold-formed steels were calculated using Direct Strength Method. The experimental data is collected from the tests that were conducted at different universities. The critical buckling strength of the members were calculated using Abaqus. Microsoft excel is used to generate the equations. The safety and resistance factors for the designed equations were calculated using “Load and resistance factor design” and “Allowable strength design” from North American Cold-Formed Steel Specification, 2012 edition book.
Date: December 2015
Creator: Dara, Martin Luther
Partner: UNT Libraries

Quasi-Static Analysis for Subsidence of Stacked B-25 Boxes

Description: This paper presents a quasi-static technique to evaluate the structural deformation of the four stacked B-25 boxes subjected to the static loads of overlaying soil and to determine the effect of corrosion on the deformation. Although the boxes are subjected to a static load, the structural responses of the boxes vary with time. The analytical results indeed show that the deflection, buckling and post buckling of the components of the stacked boxes occur in sequence rather than simultaneously. Therefore, it is more appropriate to treat the problems considered as quasistatic rather than static; namely, the structural response of the stacked boxes are dynamic but with very long duration. Furthermore, the finite-element model has complex contact and slide conditions between the interfaces of the adjoining components, and thus its numerical solution is more tractable by using explicit time integration schemes. The analysis covers the three corrosion scenarios following various time lengths of initial burial under an interim soil cover. The results qualitatively agree with expected differences in deformation for different degrees of corrosion subsidence potential reduction that can be achieved.
Date: May 24, 2005
Creator: Wu, Tsu-te; Jones, William E. & Phifer, Mark A.
Partner: UNT Libraries Government Documents Department

Some physics issues of carbon stripping foils

Description: Carbon foils are widely used in charge-exchange injection in high intensity hadron accelerators. There are a number of physics issues associated with the use of carbon foils, including stripping efficiency, energy deposition and foil lifetime (temperature rise, mechanical stress and buckling, etc.). This paper will give a brief discussion of these issues.
Date: June 1, 2007
Creator: Chou, W.; Lackey, J.; Tang, Z.; Yoon, P.; /Fermilab; Kostin, M. et al.
Partner: UNT Libraries Government Documents Department