Comparison of Handbook and 3-D Finite Element Analysis LEFM Solutions for a Threaded Fastener

2013 ◽  
Author(s):  
Daniel Sommerville ◽  
Minghao Qin ◽  
Matthew Walter
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Crack Growth ◽  
Initial Crack ◽  
Element Analysis ◽  
Linear Elastic ◽  
Similar Work ◽  
Flaw Tolerance ◽  
License Renewal ◽  
Inspection Techniques

As part of license renewal activities, many Boiling Water Reactor utilities must assess the integrity of bolted components within the reactor pressure vessel. Since inspection techniques capable of identifying cracking in the threaded regions of the core plate bolting do not currently exist it is important for flaw tolerance evaluations to be performed with as much accuracy as possible in order to obtain realistic inspection intervals and to assess the degree of redundancy in the bolted joint designs. Both 3-D finite element analysis and handbook linear elastic fracture mechanics solutions are used to assess the flaw tolerance of a core plate bolt design. Consideration of the relevant degradation and crack growth mechanisms is given for both initial crack configuration(s) and crack growth calculations. The 3-D finite element analysis is performed to investigate the effects of various simplifications in the available handbook solutions presented in the literature. The results of the flaw tolerance evaluations using both methods are compared and conclusions drawn regarding the applicability of the available handbook solutions for similar work in the future.

Application of ASME Code Section XI Appendix L Using 3-D Finite Element Analyses

2020 ◽  
Author(s):  
Charles Fourcade ◽  
Minji Fong ◽  
James Axline ◽  
Do Jun Shim ◽  
Chris Lohse ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Crack Growth ◽  
Cyclic Stress ◽  
Finite Element Analyses ◽  
Element Analysis ◽  
Aspect Ratios ◽  
Flaw Tolerance ◽  
Asme Code ◽  
Stress Ratios

Abstract As part of a fatigue management program for subsequent license renewal, a flaw tolerance evaluation based on ASME Code, Section XI, Appendix L may be performed. The current ASME Code, Section XI, Appendix L flaw tolerance methodology requires determination of the flaw aspect ratio for initial flaw size calculation. The flaw aspect ratios listed in ASME Section XI, Appendix L, Table L-3210-2, for austenitic piping for example, are listed as a function of the membrane-to-gradient cyclic stress ratio. The Code does not explicitly describe how to determine the ratio, especially when utilizing complex finite element analyses (FEA), involving different loading conditions (i.e. thermal transients, piping loads, pressure, etc.). The intent of the paper is to describe the methods being employed to determine the membrane-to-gradient cyclic stress ratios, and the corresponding flaw aspect ratios (a/l) listed in Table L-3210-2, when using finite element analysis methodology. Included will be a sample Appendix L evaluation, using finite element analysis of a pressurized water reactor (PWR) pressurizer surge line, including crack growth calculations for circumferential flaws in stainless steel piping. Based on this example, it has been demonstrated that, unless correctly separated, the membrane-to-gradient cyclic stress ratios can result in extremely long initial flaw lengths, and correspondingly short crack growth durations.

scholarly journals Mechanical behavior of ballasted railway track stabilized with polyurethane: A finite element analysis

2018 ◽  
Vol 251 ◽  
pp. 04056 ◽  
Author(s):  
Zelimkhan Khakiev ◽  
Alexander Kruglikov ◽  
Georgy Lazorenko ◽  
Anton Kasprzhitskii ◽  
Yakov Ermolov ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Mechanical Behavior ◽  
Finite Element Simulation ◽  
Elasticity Modulus ◽  
Railway Track ◽  
Binding Agent ◽  
Element Analysis ◽  
Linear Elastic ◽  
Element Simulation

Analysis of mechanical behavior of ballast shoulder of railway track reinforced by polyurethane binding agent has been performed by the method of finite-element simulation Limitation of the model of linear-elastic properties of geocomposite has been displayed. Dependence of elasticity modulus of geocomposite on deformation value has been suggested. Influence of penetration depth of polyurethane binding agent on behavior of railway track construction under different train loads has been studied.

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