Showing papers on "Static analysis published in 1973"
1 Jan 1973
TL;DR: This chapter aims at presenting fundamental concepts for the implementation of the finite-element method, with primary emphasis on static analysis based upon the displacement method.
Abstract: Publisher Summary This chapter aims at presenting fundamental concepts for the implementation of the finite-element method, with primary emphasis on static analysis based upon the displacement method. The correct interpretation of information feedback from the user's side in the course of the development of a large-scale system should have a significant effect upon its applicability. Thus the ideal developers of computer software for the application of finite element methods would be design engineers with several years of experience in the development of large computer systems and with some basic understanding of numerical analysis. The internal data are handled in the internal machine representation, thus excluding transferability between computers with different word length. All internal data handling can be concentrated in a separate data retrieval package with sufficient parametric generality to enable its adaptation to a large spectrum of computer configurations. The solution of the linear load-deflection equations is usually the most time-consuming computation step in the displacement method. As the finite-element method is ideally suited for analyzing highly complex structures, problems with several thousand unknowns occur frequently.
36 citations
1 Apr 1973
TL;DR: In this paper, the field method for linear static analysis of open branch shells of revolution under asymmetric loads has been proposed, which eliminates the well-known numerical problem of long subintervals associated with the rapid growth of extraneous solutions.
Abstract: The field method is developed for arbitrary open branch domains subjected to general linear boundary conditions. Although closed branches are within the scope of the method, they are not treated here. The numerical feasibility of the method has been demonstrated by implementing it in a computer program for the linear static analysis of open branch shells of revolution under asymmetric loads. For such problems the field method eliminates the well-known numerical problem of long subintervals associated with the rapid growth of extraneous solutions. Also, the method appears to execute significantly faster than other numerical integration methods.
7 citations
1 Jul 1973
TL;DR: In this paper, the NASTRAN structural analysis program was used to investigate the dynamic properties of thin primary mirrors suitable for use in large orbiting astronomical telescopes, including mode shapes and modal frequencies for several thin, homogeneous, isotropic mirrors.
Abstract: The NASTRAN structural analysis program was used to investigate the dynamic properties of thin primary mirrors suitable for use in large orbiting astronomical telescopes. An analysis is included of the mode shapes and modal frequencies for several thin, homogeneous, isotropic mirrors. Typical cases include two different mirror diameters, two different diameter-to-thickness ratios, and both a mirror without and a mirror with a central hole that is 22 percent of the mirror diameter. The finite-element structural model is evaluated by comparing the NASTRAN generated results with theoretical values for a simply supported, flat, circular mirror. The same model is then used for evaluating the spherical mirrors. The mode shapes and frequencies of a 0.762-meter-diameter mirror with a 60-to-1 diameter-to-thickness ratio and a three-point rigid kinematic (not overconstrained) mount are calculated and plotted for comparison with results obtained previously from the SAMIS structural analysis program for this same mirror. A static analysis is also shown for comparison with experimentally obtained influence coefficients.
1 citations