An Improved Joint Model and Equations for Flexibility of Tubular Joints

1990 ◽  
Vol 112 (2) ◽  
pp. 157-168 ◽  
Author(s):  
Y. Ueda ◽  
S. M. H. Rashed ◽  
K. Nakacho
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Bending Moment ◽  
Joint Model ◽  
Initial Stiffness ◽  
Element Analysis ◽  
Joint Flexibility ◽  
Elastic Plastic ◽  
Tubular Joints ◽  
Different Types

In tubular frames with simple joints, joints may show considerable flexibility in the elastic as well as the elastic-plastic ranges. Such flexibility may have large effects on the behavior of the structure as a whole. In a previous paper, an effective simple model of tubular joints is developed. The model takes account of joint flexibility in the elastic as well as the elastic-plastic ranges based on elastic-fully plastic load-displacement relatioships. In this paper an improved joint model is presented to provide better accuracy while maintaining simplicity. The accuracy of the model is confirmed through comparisons with results of finite element analysis. Equations to evaluate the initial stiffness of tubular T and Y-joints when braces are subjected to axial compression or in-plane bending moment are also presented. Such equations for different types of joints in different loading conditions are needed in order to avoid expensive calculations to evaluate the initial stiffness of joints.

A Study on Effect of Shape Irregularities on Collapse Loads of Pipe Bends with Critical Circumferential Throughwall Crack under In-Plane Closing Bending

2014 ◽  
Vol 592-594 ◽  
pp. 980-984
Author(s):  
Sumesh Sasidharan ◽  
Arunachalam R. Veerappan ◽  
Subramaniam Shanmugam
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Detrimental Effect ◽  
Bending Moment ◽  
Collapse Load ◽  
Element Analysis ◽  
Elastic Plastic ◽  
Circumferential Crack ◽  
Plane Bending

The presence of thorough wall circumferential cracks has a detrimental effect on collapse load of elbows. The existing theoretical solutions do not correctly quantify the weakening effect due to the presence of the circumferential through wall crack in shape imperfect pipe bends. The present study has been done to investigate the effect of ovality and thinning on the collapse moment of 90° elbow with critical throughwall circumferential crack under in-plane bending moment using elastic-plastic finite element analysis considering large geometry change.

Development of J-Integral Solutions for Semi-Elliptical Circumferential Cracked Pipes Subjected to Internal Pressure and Bending Moment

2015 ◽  
Author(s):  
Makoto Udagawa ◽  
Jinya Katsuyama ◽  
Yoshihito Yamaguchi ◽  
Yinsheng Li ◽  
Kunio Onizawa
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Loading Condition ◽  
Bending Moment ◽  
J Integral ◽  
Surface Cracks ◽  
Element Analysis ◽  
Elastic Plastic ◽  
Piping Systems ◽  
Integral Solutions

The J-integral solutions for cracked pipes are important in crack growth calculation and failure evaluation based on the elastic-plastic fracture mechanics. One of the most important crack types in structural integrity assessment for nuclear piping systems is circumferential semi-elliptical surface crack on the inside of the pipes. Although several J-integral solutions have been provided, no solutions were developed at both the deepest and the surface points of circumferential semi-elliptical surface cracks in pipes. In this study, with backgrounds described above, the J-integral solutions of circumferential semi-elliptical surface cracks on the inside of the pipe were developed by numerical finite element analyses. Three dimensional elastic-plastic analyses were performed considering different material properties, pipe sizes, crack dimensions and, especially, combined loading condition of internal pressure and bending moment which is a typical loading condition for nuclear piping systems. The J values at both the deepest and the surface points were extracted from finite element analysis results. Moreover, in order to benefit users in practical applications, a pair of convenient J-integral estimation equations were developed based on the calculated J values at the deepest and the surface points. Finally, the accuracy and applicability of the convenient equations were confirmed by comparing with the provided stress intensity factor solutions in elastic region and with finite element analysis results in elastic-plastic region.

Elastic and elastic-plastic finite element analysis of hollow tubes with axisymmetric internal projections under combined axial and pressure loading

2001 ◽  
Vol 36 (4) ◽  
pp. 373-390 ◽  
Author(s):  
S. J Hardy ◽  
M. K Pipelzadeh ◽  
A. R Gowhari-Anaraki
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Internal Pressure ◽  
Plastic Material ◽  
Axial Loading ◽  
Material Model ◽  
Pressure Loading ◽  
Element Analysis ◽  
Elastic Plastic ◽  
Applied Loading

This paper discusses the behaviour of hollow tubes with axisymmetric internal projections subjected to combined axial and internal pressure loading. Predictions from an extensive elastic and elastic-plastic finite element analysis are presented for a typical geometry and a range of loading combinations, using a simplified bilinear elastic-perfectly plastic material model. The axial loading case, previously analysed, is extended to cover the additional effect of internal pressure. All the predicted stress and strain data are found to depend on the applied loading conditions. The results are normalized with respect to material properties and can therefore be applied to geometrically similar components made from other materials, which can be represented by the same material models.

scholarly journals A Review on Numerical Analysis of RC Flat Slabs Exposed to Fire

2020 ◽  
Vol 27 (1) ◽  
pp. 1-5
Author(s):  
Hanadi Naji ◽  
Nibras Khalid ◽  
Mutaz Medhlom
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Numerical Analysis ◽  
Bending Moment ◽  
Mechanical And Thermal Properties ◽  
Vertical Deflection ◽  
Element Analysis ◽  
Flat Slabs ◽  
Numerical Studies ◽  
The Finite Element Analysis

This paper aims at presenting and discussing the numerical studies performed to estimate the mechanical and thermal behavior of RC flat slabs at elevated temperature and fire. The numerical analysis is carried out using finite element programs by developing models to simulate the performance of the buildings subjected to fire. The mechanical and thermal properties of the materials obtained from the experimental work are involved in the modeling that the outcomes will be more realistic. Many parameters related to fire resistance of the flat slabs have been studied and the finite element analysis results reveal that the width and thickness of the slab, the temperature gradient, the fire direction, the exposure duration and the thermal restraint are important factors that influence the vertical deflection, bending moment and force membrane of the flat slabs exposed to fire. However, the validation of the models is verified by comparing their results to the available experimental date. The finite element modeling contributes in saving cost and time consumed by experiments.

Sign in / Sign up

Export Citation Format

Share Document