Approximate limit load evaluation of structural frames using linear elastic analysis

2007 ◽  
Vol 29 (3) ◽  
pp. 296-304 ◽  
Author(s):  
Claudia C. Marin-Artieda ◽  
Gary F. Dargush
Keyword(s):  
Limit Load ◽  
Elastic Analysis ◽  
Linear Elastic ◽  
Structural Frames ◽  
Load Evaluation ◽  
Approximate Limit

Stress Analysis and Design for Cyclic Loading

2000 ◽  
Vol 122 (4) ◽  
pp. 427-430
Author(s):  
P. Carter
Keyword(s):  
Thermal Loading ◽  
Limit Load ◽  
Elastic Analysis ◽  
Analysis And Design ◽  
Linear Elastic ◽  
Inelastic Analysis ◽  
Nonlinear Elastic Analysis ◽  
Comprehensive Framework ◽  
Nonlinear Elastic ◽  
Effective Design

A finite element implementation of rapid cycle analysis is described and demonstrated. It forms part of a comprehensive framework for static structural analysis which consists of: linear elastic analysis, limit load or nonlinear elastic analysis, and rapid cycle analysis. This approach allows for complex material and loading behavior, but is computationally more efficient and easier to perform than full inelastic analysis. It indicates more complex behavior than can be inferred from linear elastic analysis. The objective of this paper is to calculate shakedown, reverse plasticity, ratcheting, and the increase in strain rate as a result of cyclic mechanical and thermal loading. Results are presented in the form of interaction diagrams, similar to the O’Donnell-Porowski plot in the ASME BPV Code, which are effective design tools. [S0094-9930(00)01604-8]

Estimating Lower Bound Limit Loads for Structures Subjected to Multiple Loads

2015 ◽  
Vol 137 (4) ◽  
Author(s):  
C. Hari Manoj Simha ◽  
Reza Adibi-Asl
Keyword(s):  
Lower Bound ◽  
Elastic Stress ◽  
Limit Load ◽  
Selection Method ◽  
Elastic Analysis ◽  
Limit Loads ◽  
Linear Elastic ◽  
Multiple Loads ◽  
Cracked Structures ◽  
Appl Math

It is shown that the extended variational theorem of Mura et al. (1965, “Extended Theorems of Limit Analysis,” Q. Appl. Math., 23(2), pp. 171–179) can be applied to structures subjected to more than one load and be used to compute lower bound limit load multipliers. In particular, the multiplier proposed by Simha and Adibi-Asl (2011, “Lower Bound Limit Load Estimation Using a Linear Elastic Analysis,” ASME J. Pressure Vessel Technol., 134(2), p. 021207), which can be computed using an elastic stress field, is shown to be a lower bound. Furthermore, it is demonstrated that lower bound limit load for cracked structures may also be computed using a subvolume selection method. No iterations or elastic modulus adjustment are required. Several analytical and numerical examples that illustrate the procedure are presented.

Comparison of Limit Load, Linear and Nonlinear FE Analyses of Stresses in a Large Nozzle-to-Shell Diameter Ratio Application

2004 ◽  
Author(s):  
Michael A. Porter ◽  
Steven R. Massey ◽  
Dennis H. Martens
Keyword(s):  
Limit Load ◽  
Diameter Ratio ◽  
Elastic Analysis ◽  
Tube Sheet ◽  
Finite Element Analyses ◽  
Linear Elastic ◽  
Modeling Techniques ◽  
Linear And Nonlinear ◽  
Load Analysis ◽  
Comparison Of The Results

The analyses address a nominal 62-inch diameter nozzle in a nominal 124-inch diameter shell with a reinforcement pad. The nozzle is in a channel of a heat exchanger. This results in stiffening of the shell (adjacent to the nozzle) by the tube sheet and the channel head. The results of a WRC 297 analysis, linear elastic analysis, limit load analysis and plastic analysis are compared. The finite element analyses were accomplished utilizing commercial software and typical modeling techniques. As there is significant variance in the results derived with the different methodologies, the authors discuss the comparison of the results.

Reference Volume Consideration in the mα-Tangent Method Based Linear Elastic Analysis

2011 ◽  
Author(s):  
R. Adibi-Asl ◽  
M. M. Hossain ◽  
S. L. Mahmood ◽  
P. S. R. Gudimetla ◽  
R. Seshadri
Keyword(s):  
Finite Element ◽  
Rapid Determination ◽  
Limit Load ◽  
Elastic Analysis ◽  
Element Analysis ◽  
Limit Loads ◽  
Linear Elastic ◽  
Reference Volume ◽  
Tangent Method

Limit loads for pressure components are determined on the basis of a single linear elastic finite element analysis by invoking the concept of kinematically active (reference) volume in the context of the “mα-tangent” method. The resulting technique enables rapid determination of lower bound limit load for pressure components by eliminating the kinematically inactive volume. This method is applied to a number of practical components with different percentages of inactive volume. The results are compared with the corresponding inelastic finite element results, or available analytical solutions.

Lower Bound Limit Load Estimation Using a Linear Elastic Analysis

2012 ◽  
Vol 134 (2) ◽  
Author(s):  
C. Hari Manoj Simha ◽  
R. Adibi-Asl
Keyword(s):  
Lower Bound ◽  
Deformation Theory ◽  
Elastic Stress ◽  
Limit Load ◽  
Load Estimation ◽  
Elastic Analysis ◽  
Numerical Examples ◽  
Linear Elastic ◽  
Plastic Localization ◽  
Appl Math

We present a scheme that utilizes one elastic stress field (no iterations) to compute lower bound limit load multipliers of structures that collapse through gross (or localized) plasticity. A criterion to distinguish between these collapse modes is presented. For structures that collapse through gross plasticity, we demonstrate that the m′ multiplier proposed by Mura et al. (1965, Extended Theorems of Limit Analysis,” Q. Appl. Math., 23(2), pp. 171–179) is a lower bound in the context of deformation theory. For structures that undergo plastic localization at collapse, we present a criterion that identifies (approximately) the subvolumes of the structure that participate in the collapse. Multiplier m′ is computed over the selected subvolumes, denoted as m'S, and demonstrated to be a lower bound multiplier in the context of deformation theory. We consider numerical examples of structures that collapse by localized or gross plasticity and show that our proposed multiplier is lower than the corresponding multiplier obtained through elastic–plastic analysis and the proposed multiplier is not overly conservative.

scholarly journals Variation Simulation of Fixtured Assembly Processes for Compliant Structures Using Piecewise-Linear Analysis

2005 ◽  
Author(s):  
Michael L. Stewart ◽  
Kenneth W. Chase
Keyword(s):  
Piecewise Linear ◽  
Element Model ◽  
Linear Analysis ◽  
Elastic Analysis ◽  
Variation Analysis ◽  
Linear Elastic ◽  
Final Assembly ◽  
Compliant Part ◽  
Assembly Operations ◽  
Variation Simulation

While variation analysis methods for compliant assemblies are becoming established, there is still much to be done to model the effects of multi-step, fixtured assembly processes statistically. A new method is introduced for statistically analyzing compliant part assembly processes using fixtures. This method yields both a mean and a variant solution, which can characterize an entire population of assemblies. The method, called Piecewise-Linear Elastic Analysis, or PLEA, is developed for predicting the residual stress, deformation and springback variation resulting from fixtured assembly processes. A comprehensive, step-by-step analysis map is presented for introducing dimensional and surface variations into a finite element model, simulating assembly operations, and calculating the error in the final assembly. PLEA is validated on a simple, laboratory assembly and a more complex, production assembly. Significant modeling issues are resolved as well as the comparison of the analytical to physical results.

Implementation of p and h-p Versions of the Finite Element Method

1992 ◽  
Author(s):  
Ye-Chen Lai ◽  
Timothy C. S. Liang ◽  
Zhenxue Jia
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Elastic Analysis ◽  
Two Dimensional ◽  
The Finite Element Method ◽  
Shape Functions ◽  
Linear Elastic ◽  
Finite Element Software ◽  
Analysis Process ◽  
Adaptive Analysis

Abstract Based on hierarchic shape functions and an effective convergence procedure, the p-version and h-p adaptive analysis capabilities were incorporated into a finite element software system, called COSMOS/M. The range of the polynomial orders can be varied from 1 to 10 for two dimensional linear elastic analysis. In the h-p adaptive analysis process, a refined mesh are first achieved via adaptive h-refinement. The p-refinement is then added on to the h-version designed mesh by uniformly increasing the degree of the polynomials. Some numerical results computed by COSMOS/M are presented to illustrate the performance of these p and h-p analysis capabilities.

Linear-elastic analysis of seismic responses of porcelain post electrical equipment

2019 ◽  
Vol 201 ◽  
pp. 109848 ◽  
Author(s):  
Qiang Xie ◽  
Chang He ◽  
Bin Jiang ◽  
Zhenyu Yang
Keyword(s):  
Electrical Equipment ◽  
Elastic Analysis ◽  
Seismic Responses ◽  
Linear Elastic
Sign in / Sign up

Export Citation Format

Share Document