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Small Bending and Stretching of Sandwich-Type Shells

Description: "A theory has been developed for small bending and stretching of sandwich-type shells. This theory is an extension of the known theory of homogeneous thin elastic shells. It was found that two effects are important in the present problem, which are not normally of importance in the theory of curved shells: (1) the effect of transverse shear deformation and (2) the effect of transverse normal stress deformation" (p. 1).
Date: 1950
Creator: Reissner, Eric
Partner: UNT Libraries Government Documents Department

Loads Imposed on Intermediate Frames of Stiffened Shells

Description: "The loads imposed on intermediate frames by the curvature of the longitudinal and by the diagonal-tension effects are treated. A new empirical method is proposed for analyzing diagonal-tension effects. The basic formulas of the pure diagonal-tension theory are used, and the part of the total shear S carried by diagonal tension is assumed to be given the expression S (sub DT) = S (1-tau sub o/tau)(sup n) where tau (sub o) is the critical shear stress, tau the total (nominal shear stress), and n = 3 - sigma/tau where sigma is the stress in the intermediate frame. Numerical examples illustrate all cases treated" (p. 1).
Date: February 1939
Creator: Kuhn, Paul
Partner: UNT Libraries Government Documents Department

On the Mechanism of Buckling of a Circular Cylindrical Shell Under Axial Compression

Description: The present paper deals with the buckling of a circular cylindrical shell under axial compression from the viewpoint of energy and the characteristics of deformation. It is shown first, both theoretically and experimentally, that the reason why the buckling of a cylindrical shell is quite different from that of a flat plate is attributable to the existence of a nearly developable surface far apart from the original cylindrical surface. Based upon this result, the experimental fact that the buckling is really not general but local, that is, that the buckled region is limited axially to a range of 1.5 times the wave length of the lobe, is explained by the theoretical result that the minimum buckling load is smaller in the local buckling than in the general buckling case.
Date: July 1955
Creator: Yoshimura, Yoshimaru
Partner: UNT Libraries Government Documents Department

Notes on the Foundations of the Theory of Small Displacements of Orthotropic Shells

Description: Note presenting a survey that has been made of the various systems of equations which have been given in the literature for the analysis of small deflections of thin elastic shell. A new system of equations has been derived for the analysis of shells, which includes the effects of transverse shear and normal stresses.
Date: March 1949
Creator: Hildebrand, F. B.; Reissner, E. & Thomas, G. B.
Partner: UNT Libraries Government Documents Department

A Simplified Method of Elastic-Stability Analysis for Thin Cylindrical Shells 1: Donnell's Equation

Description: "The equation for the equilibrium of cylindrical shells introduced by Donnell in NACA Technical Report no. 479 to find the critical stresses of cylinders in torsion is applied to find critical stresses for cylinders with simply supported edges under other loading conditions. It is shown that by this method solutions may be obtained very easily and the results in each case may be expressed in terms of two nondimensional parameters, one dependent on the critical stress and the other essentially determined by the geometry of the cylinder. The influence of boundary conditions related to edge displacements in the shell median surface is discussed" (p. 1).
Date: June 1947
Creator: Batdorf, S. B.
Partner: UNT Libraries Government Documents Department

Experimental stress analysis of stiffened cylinders with cutouts: Shear load

Description: A cylindrical semimonocoque shell of circular cross section was mounted as a cantilever and loaded by a direct shear at the tip. The cylinder was tested with no cutout, with a rectangular cutout on the tension side, and with the cutout centered on the neutral axis on one side of the cylinder. The cutout was successively enlarged through six sizes varying from 30 degrees to 130 degrees in circumference and from 1 and 2 bays in length. Strain measurements were made with resistance-type wire strain gages near the cutout on the stringers, the skin, and the rings for each case, and the stresses obtained are presented in tables. (author).
Date: July 1954
Creator: Schlechte, Floyd R. & Rosecrans, Richard
Partner: UNT Libraries Government Documents Department

Static Longitudinal Stability Characteristics of a Series of 90-Millimeter Artillery Shells at Mach Numbers of 0.8, 0.9, 1.0, and 1.2

Description: Wind-tunnel tests have been made to determine the static longitudinal stability of several models of a short-range artillery shell at Mach numbers of 0.8, 0.9, 1.0, and 1.2. The results of the tests indicated that the best of the spool-shaped shells was statically stable in pitch at all test Mach numbers for an angle-of-attack range up to about 10 degrees. The best of the finned shells was stable to a maximum angle of attack of about 6 degrees.
Date: April 10, 1956
Creator: Spooner, Stanley H.
Partner: UNT Libraries Government Documents Department

Basic Differential Equations in General Theory of Elastic Shells

Description: "The shell shall be considered as a three-dimensional continuous medium; for the coordinate surface, the middle surface of the shell shall be assumed parallel to the bounding surfaces. Let alpha and beta be the curvilinear orthogonal coordinates of this surface, coinciding with the lines of principal curvatures, and gamma the distance along the normal from the point (alpha,beta) of the coordinate surface to any point (alpha, beta, gamma) of the shell" (p. 1).
Date: February 1951
Creator: Vlasov, V. S.
Partner: UNT Libraries Government Documents Department

Stress Analysis of Circular Semimonocoque Cylinders With Cutouts by a Perturbation Load Technique

Description: "A method is presented for analyzing the stresses about a cutout in a circular cylinder of semimonocoque construction. The method involves the use of so-called perturbation solutions which are superposed on the stress distribution that would exist in the structure with no cutout in such a way as to give the effects of a cutout. The method can be used for any loading case for which the structure without the cutout can be analyzed and is sufficiently versatile to account for stringer and shear reinforcement about the cutout" (p. 1).
Date: September 1954
Creator: McComb, Harvey G., Jr.
Partner: UNT Libraries Government Documents Department

On the Flutter of Cylindrical Shells and Panels Moving in a Flow of Gas

Description: The equations of shells are taken in the form of the general technical theory of shallow shells and shells of medium length. The aerodynamic forces acting on a shell are taken into account only as forces of excess pressure according to the formula proposed by A.A. Iliushin in reference 3.
Date: September 1958
Creator: Stepanov, R. D.
Partner: UNT Libraries Government Documents Department

On the Calculation of Shallow Shells

Description: This paper considers a sufficiently thin shallow shell of nonzero Gaussian curvature. It also presents a system of symmetrically constructed differential equations, constructed by the mixed method through the stress function and the displpacement function.
Date: December 1956
Creator: Ambartsumyan, S. A.
Partner: UNT Libraries Government Documents Department

Stability of the Cylindrical Shell of Variable Curvature

Description: "This report is a first attempt to devise a calculation method for representing the buckling behavior of cylindrical shells of variable curvature. The problem occurs, for instance, in dimensioning wing noses, the stability of which is decisively influenced by the variability of curvature. The calculation is made possible by simplifying the stability equations (permissible for the shell of small curvature) and by assuming that the curvature 1/R as a function of the arc lengths can be represented by a very few Fourier terms" (p. 1).
Date: July 1951
Creator: Marguerre, Karl
Partner: UNT Libraries Government Documents Department

Contribution to the Design of Plywood Shells

Description: "The writer sets out to prove by calculation and experiment that by extensive utilization of the skin to carry axial load (reduction of stringer spacing) the stringer sections can be made small enough to afford a substantial saving in structural weight. This saving ranges from 5 to about 40 percent" (p. 1).
Date: October 1942
Creator: Blumrich, S.
Partner: UNT Libraries Government Documents Department

Stability of Cylindrical and Conical Shells of Circular Cross Section, with Simultaneous Action of Axial Compression and External Normal Pressure

Description: "We consider in this report the determination of the upper limit of critical loads in the case of simultaneous action of a compressive force, uniformly distributed over plane cross sections, and of isotropic external normal pressure on cylindrical or conical shells of circular cross section. As a starting point we use the differential equations for neutral equilibrium of conical shells which have been used for the solution of the problem of stability of conical shells under torsion and under axial compression; upon solution of the problem it is possible to satisfy all boundary conditions, in contrast to the report where no attention is paid to the fulfillment of the boundary conditions, and to the report where only part of the boundary conditions are satisfied by solution of the problem according to Galerkin's method" (p. 1).
Date: April 1958
Creator: Mushtari, K. M. & Sachenkov, A. V.
Partner: UNT Libraries Government Documents Department

A Low-Speed Investigation of the Magnus Effects on a Sting-Mounted Model of a Typical Mortar Shell

Description: Memorandum presenting an investigation made in the stability tunnel with a 2.3-scale spinning model of a typical mortar shell. The tests were made to measure the aerodynamic forces and moments acting on a typical spinning mortar shell. Results regarding the basic configuration, effect of changes in tail configuration, effect of changes in the nose configuration, and comparison of mortar shell and antisubmarine rocket are provided.
Date: January 2, 1957
Creator: Lichtenstein, Jacob H.
Partner: UNT Libraries Government Documents Department

Principle and Application of Complementary Energy Method for Thin Homogeneous and Sandwich Plates and Shells With Finite Deflections

Description: Note presenting the principle of complementary energy in the nonlinear elasticity theory, which is shown to be derivable from the principle of potential energy by a Legendre type of transformation. The expression of the complementary energy is derived for homogeneous and sandwich plates and shells with large deflections. The stress-strain relations are derived for homogeneous shells, sandwich plates, and sandwich shells.
Date: February 1952
Creator: Wang, Chi-Teh
Partner: UNT Libraries Government Documents Department

Torsional Stiffness of Thin-Walled Shells Having Reinforcing Cores and Rectangular, Triangular, or Diamond Cross Section

Description: A theoretical investigation is presented of the torsional stiffness of thin-walled aerodynamic surfaces filled with cores which stabilize the skins. Rectangular, slender triangular, and slender diamond cross sections are considered. Results for the torsional stiffness constants are shown graphically.
Date: October 1956
Creator: McComb, Harvey G., Jr.
Partner: UNT Libraries Government Documents Department

Calculation of Load Distribution in Stiffened Cylindrical Shells

Description: "Thin-walled shells with strong longitudinal and transverse stiffening (for example, stressed-skin fuselages and wings) may, under certain simplifying assumptions, be treated as static systems with finite redundancies. In this report the underlying basis for this method of treatment of the problem is presented and a computation procedure for stiffened cylindrical shells with curved sheet panels indicated. A detailed discussion of the force distribution due to applied concentrated forces is given, and the discussion illustrated by numerical examples which refer to an experimentally determined circular cylindrical shell" (p. 1).
Date: June 1938
Creator: Ebner, H. & K├Âller, H.
Partner: UNT Libraries Government Documents Department

Torsional Stiffness of Thin-Walled Shells Having Reinforcing Cores and Rectangular, Triangular, or Diamond Cross Section

Description: "A theoretical investigation has been made of the Saint-Venant torsion of certain composite bars. These bars are composed of two materials -- one material in the form of a thin-walled cylindrical shell and the other material in the form of a core which fills the interior of the shell and is bonded to it. An approximate boundary-value problem is formulated on assumptions similar to those of the theory of torsion of hollow thin-walled shells (Bredt theory)" (p. 771).
Date: June 7, 1956
Creator: McComb, Harvey G., Jr.
Partner: UNT Libraries Government Documents Department

On the Theory of Anisotropic Shallow Shells

Description: A numerical analysis of thin-walled shallow shells is presented. Equations of equilibrium and relations between deformations and stresses are included along with fundamental differential equations.
Date: December 1956
Creator: Ambartsumyan, S. A.
Partner: UNT Libraries Government Documents Department

On the Theory of Thin Shallow Shells

Description: This report is concerned with the theory of thin shallow shells. It does not employ the lines of curvature as the coordinate system, but employs "almost cartesian coordinates" or the coordinates obtained by cutting the surface into two mutually orthogonal systems of parallel planes.
Date: December 1956
Creator: Nazarov, A. A.
Partner: UNT Libraries Government Documents Department

Computation of Thin-Walled Prismatic Shells

Description: "We consider a prismatic shell consisting of a finite number of narrow rectangular plates and having in the cross-section a finite number of closed contours (fig. 1(a)). We shall assume that the rectangular plates composing the shell are rigidly joined so that there is no motion of any kind of one plate relative to the others meeting at a given connecting line. The position of a point on the middle prismatic surface is considered to be defined by the coordinate z, the distance to a certain initial cross-section z = O, end the coordinate s determining its position on the contour of the cross-section" (p. 1).
Date: June 1949
Creator: Vlasov, V. Z.
Partner: UNT Libraries Government Documents Department