Review and Comparison of Buckling Methodologies for ASME B&PV Code, Section III, Subsection NF Linear Piping Restraints

2016 ◽  
Author(s):  
Shrikant Nargund ◽  
Dennis K. Williams
Keyword(s):  
Finite Element ◽  
Large Deformation ◽  
Plastic Material ◽  
Slenderness Ratio ◽  
Structural Member ◽  
Buckling Load ◽  
Material Behavior ◽  
Deformation Method ◽  
Critical Buckling Load ◽  
Hexahedral Elements

Piping supports and restrains are required to follow the design requirements as mentioned in ASME B&PV Code, Section III, Subsection NF. One of the requirements indicates the necessity of calculating the critical buckling stresses for the members that are subjected to a compressive loading. This paper discusses the prescribed requirements in the Code that specifically address the considerations of the stability and buckling load capacities of linear piping restraints (i.e., struts). The finite element modeling of various strut geometries and the results of the buckling analyses of a slender (slenderness ratio Kl/r greater than or equal to 100) structural members using various finite element solution techniques are presented herein. Specifically, three types of finite element analysis are conducted in an effort to define the critical buckling load for the subject structural member, and include the traditional linear (Eigen value) Euler method; the nonlinear, second order large deformation method; and finally, the nonlinear large deformation method that incorporates nonlinear elastic-plastic material behavior. These techniques are employed for a hollow cylindrical structural member (i.e., a strut assembly) with varying cross sections along its length. Finite element model consists of three dimensional hexahedral elements in combination with beam elements for the general purpose a finite element solver ANSYS. The critical buckling load is calculated in each case, thereby predicting the load at which instability will occur in the structural member. The results obtained from the aforementioned techniques are then compared both numerically and qualitatively with an appropriate explanation of the purpose and usefulness of each particular result with respect to the intent of the ASME B&PV Code, Section III, Subsection NF requirements. The results show significant variations (as expected) based on differences in the assumptions and techniques employed in the respective analyses.

Review and Comparison of Buckling Methodologies for ASME B&PV Code Linear Piping and Component Restraints

2017 ◽  
Author(s):  
Phillip Wiseman ◽  
Zara Z. Hoch ◽  
Shrikant S. Nargund
Keyword(s):  
Finite Element ◽  
Large Deformation ◽  
Plastic Material ◽  
Slenderness Ratio ◽  
Beam Theory ◽  
Euler Method ◽  
Buckling Load ◽  
Material Behavior ◽  
Finite Element Analyses ◽  
Deformation Method

Piping and component restraints are required to follow the design requirements as mentioned in ASME Boiler and Pressure Vessel Code, Section III, Subsection NF. One of the requirements indicates the necessity of calculating the critical buckling stresses for the members that are subjected to a compressive loading. This paper discusses the prescribed requirements in the Code that specifically address the considerations of the stability and buckling load capacities of linear piping and component restraints (i.e., struts). The finite element modeling of various strut geometries and the results of the buckling analyses of slender structural members (slenderness ratio, Kl/r, greater than or equal to 100) using various finite element solution techniques are presented herein. Specifically, three types of finite element analyses are conducted in an effort to define the critical buckling load for the subject structural member. These three finite element analyses include the traditional linear (Eigen value) Euler method; the nonlinear, second order large deformation method; and finally, the nonlinear large deformation method that incorporates nonlinear elastic-plastic material behavior. Additionally, two closed form solutions using strain energy method and Euler-Bernoulli beam theory are conducted on the same strut geometries. The results obtained from the aforementioned techniques are then compared both numerically and qualitatively with an appropriate explanation of the purpose and usefulness of each particular result with respect to the intent of the ASME B&PV Code, Section III, Subsection NF requirements. The results show significant variations based on differences in the assumptions and techniques employed in the respective analyses and simply applying the identical margin of safety to each technique does not yield consistent outcomes. As a result of the discussion we get an insight about the axial compression allowable stress equations and factors as defined in the ASME B&PV Code and how they should be refined depending on the type of buckling analysis we choose to conduct.

scholarly journals Non-Linear Buckling Analysis of Axially Loaded Column with Non-Prismatic I-Section

2019 ◽  
Vol 5 (3) ◽  
pp. 263
Author(s):  
Adrian Pramudita Dharma ◽  
Bambang Suryoatmono
Keyword(s):  
Finite Element ◽  
Cross Section ◽  
Cross Sections ◽  
Plastic Material ◽  
Slenderness Ratio ◽  
Buckling Load ◽  
Coefficient Of Determination ◽  
Average Cross Section ◽  
Perfectly Plastic ◽  
Elastic Perfectly Plastic

In order to use material efficiently, non-prismatic column sections are frequently employed. Tapered-web column cross-sections are commonly used, and design guides of such sections are available. In this study, various web-and-flange-tapered column sections were analysed numerically using finite element method to obtain each buckling load assuming the material as elastic-perfectly plastic material. For each non-prismatic column, the analysis was also performed assuming the column is prismatic using average cross-section with the same length and boundary conditions. Buckling load of the prismatic columns were obtained using equation provided by AISC 360-16. This study proposes a multiplier that can be applied to the buckling load of a prismatic column with an average cross-section to acquire the buckling load of the corresponding non-prismatic column. The multiplier proposed in this study depends on three variables, namely the depth tapered ratio, width tapered ratio, and slenderness ratio of the prismatic section. The equation that uses those three variables to obtain the multiplier is obtained using regression of the finite element results with a coefficient of determination of 0.96.

Shakedown Limit Load Determination for a Kinematically Hardening 90-Degree Pipe Bend Subjected to Constant Internal Pressure and Cyclic Bending

2007 ◽  
Author(s):  
Hany F. Abdalla ◽  
Mohammad M. Megahed ◽  
Maher Y. A. Younan
Keyword(s):  
Finite Element ◽  
Internal Pressure ◽  
Plastic Material ◽  
Kinematic Hardening ◽  
Limit Load ◽  
Material Behavior ◽  
Pipe Bend ◽  
Cyclic Bending ◽  
Perfectly Plastic ◽  
Shakedown Limit

A simplified technique for determining the shakedown limit load of a structure employing an elastic-perfectly-plastic material behavior was previously developed and successfully applied to a long radius 90-degree pipe bend. The pipe bend is subjected to constant internal pressure and cyclic bending. The cyclic bending includes three different loading patterns namely; in-plane closing, in-plane opening, and out-of-plane bending moment loadings. The simplified technique utilizes the finite element method and employs small displacement formulation to determine the shakedown limit load without performing lengthy time consuming full cyclic loading finite element simulations or conventional iterative elastic techniques. In the present paper, the simplified technique is further modified to handle structures employing elastic-plastic material behavior following the kinematic hardening rule. The shakedown limit load is determined through the calculation of residual stresses developed within the pipe bend structure accounting for the back stresses, determined from the kinematic hardening shift tensor, responsible for the translation of the yield surface. The outcomes of the simplified technique showed very good correlation with the results of full elastic-plastic cyclic loading finite element simulations. The shakedown limit moments output by the simplified technique are used to generate shakedown diagrams of the pipe bend for a spectrum of constant internal pressure magnitudes. The generated shakedown diagrams are compared with the ones previously generated employing an elastic-perfectly-plastic material behavior. These indicated conservative shakedown limit moments compared to the ones employing the kinematic hardening rule.

scholarly journals Vibration and Buckling Characteristics of Functionally Graded Graphene Nanoplatelets Reinforced Composite Beams with Open Edge Cracks

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1412 ◽  
Author(s):  
Meifung Tam ◽  
Zhicheng Yang ◽  
Shaoyu Zhao ◽  
Jie Yang
Keyword(s):  
Fundamental Frequency ◽  
Slenderness Ratio ◽  
Weight Fraction ◽  
Graphene Nanoplatelets ◽  
Functionally Graded ◽  
Buckling Load ◽  
Critical Buckling Load ◽  
Reinforced Composite ◽  
Edge Cracks ◽  
Open Edge

This paper investigates the free vibration and compressive buckling characteristics of functionally graded graphene nanoplatelets reinforced composite (FG-GPLRC) beams containing open edge cracks by using the finite element method. The beam is a multilayer structure where the weight fraction of graphene nanoplatelets (GPLs) remains constant in each layer but varies along the thickness direction. The effective Young’s modulus of each GPLRC layer is determined by the modified Halpin-Tsai micromechanics model while its Poisson’s ratio and mass density are predicted according to the rule of mixture. The effects of GPLs distribution pattern, weight fraction, geometry, crack depth ratio (CDR), slenderness ratio as well as boundary conditions on the fundamental frequency and critical buckling load of the FG-GPLRC beam are studied in detail. It was found that distributing more GPLs on the top and bottom surfaces of the cracked FG-GPLRC beam provides the best reinforcing effect for improved vibrational and buckling performance. The fundamental frequency and critical buckling load are also considerably affected by the geometry and dimension of GPL nanofillers.

Analytical Solution of Sidewise Buckling of Two-Hinged Circular Arch under Concentrated Force

2013 ◽  
Vol 676 ◽  
pp. 170-174
Author(s):  
Ju Tao Kuang ◽  
Ai Rong Liu ◽  
Qi Ca Yu ◽  
Jiang Dong Deng
Keyword(s):  
Finite Element ◽  
Analytical Solution ◽  
Lateral Displacement ◽  
Displacement Function ◽  
Buckling Load ◽  
The Finite Element Method ◽  
Concentrated Force ◽  
Critical Buckling Load ◽  
Circular Arch ◽  
Good Agreement

By the setting torsional and lateral displacement function of sidewise buckling of two-hinged circular arch under concentrated force, the single-arch structure's bending, torsional deformation and external force potential can be constructed. An analytical solution for the lateral critical buckling load of two-hinged arch is first deduced by using the energy method; the results are also compared and analyzed by the finite element method. The results show that the analytical solution of single arch’s lateral critical buckling load is in good agreement with the finite element numerical solution, and the validity of the formula is proven.

scholarly journals A Numerical Study of the Effect of Component Dimensions on the Critical Buckling Load of a GFRP Composite Strut under Uniaxial Compression

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 931 ◽  
Author(s):  
Quoc Hoan Doan ◽  
Duc-Kien Thai ◽  
Ngoc Long Tran
Keyword(s):  
Uniaxial Compression ◽  
Cross Section ◽  
Numerical Study ◽  
Slenderness Ratio ◽  
Thickness Ratio ◽  
Buckling Load ◽  
Critical Buckling Load ◽  
Channel Section ◽  
Gfrp Composite ◽  
Thin Walled

In the practical design of thin-walled composite columns, component dimensions should be wisely designed to meet the buckling resistance and economic requirements. This paper provides a novel and useful investigation based on a numerical study of the effects of the section dimensions, thickness ratio, and slenderness ratio on the critical buckling load of a thin-walled composite strut under uniaxial compression. The strut was a channel-section-shaped strut and was made of glass fiber-reinforced polymer (GFRP) composite material by stacking symmetrical quasi-isotropic layups using the autoclave technique. For the purpose of this study, a numerical finite element model was developed for the investigation by using ABAQUS software. The linear and post-buckling behavior analysis was performed to verify the results of the numerical model with the obtained buckling load from the experiment. Then, the effects of the cross-section dimensions, thickness ratio, and slenderness ratio on the critical buckling load of the composite strut, which is determined using an eigenvalue buckling analysis, were investigated. The implementation results revealed an insightful interaction between cross-section dimensions and thickness ratio and the buckling load. Based on this result, a cost-effective design was recommended as a useful result of this study. Moreover, a demarcation point between global and local buckling of the composite strut was also determined. Especially, a new design curve for the channel-section GFRP strut, which is governed by the proposed constitutive equations, was introduced to estimate the critical buckling load based on the input component dimension.

Buckling of laminated composite cylindrical skew panels

2015 ◽  
Vol 30 (9) ◽  
pp. 1175-1199
Author(s):  
Srinivasa Venkateshappa Chikkol ◽  
Prema Kumar Puttiah Wooday ◽  
Suresh Jayadevappa Yelaburgi
Keyword(s):  
Finite Element ◽  
Aspect Ratio ◽  
Laminated Composite ◽  
Buckling Load ◽  
Finite Element Solution ◽  
Element Solution ◽  
Skew Angle ◽  
Critical Buckling Load ◽  
Aluminum 7075 ◽  
Experimental Values

Experimental studies were made on isotropic cylindrical skew panels made of Aluminum 7075-T6 and laminated composite cylindrical skew panels under uniaxial compression. The experimental values of the critical buckling load ( Pcr) were determined using five different methods. The values of Pcr were also determined using MSC/Nastran and CQUAD8 finite element. The experimental values of the Pcr obtained by different methods were compared with the finite element solution. The effects of the skew angle and aspect ratio on the critical buckling load of isotropic cylindrical skew panels made of Aluminum 7075-T6 were studied. The effects of the skew angle, aspect ratio, and the laminate stacking sequence on the critical buckling load of laminated composite cylindrical skew panels were also studied. It is found that the method IV (based on a plot of applied load ( P) vs. average axial strain) yields the highest value for Pcr and method III (based on a plot of P vs. square of out-of-plane-deflection) the lowest value for Pcr. The experimental values given by method IV are seen to be closest to the finite element solution, the discrepancy being in the range of 5–23% for laminated composite cylindrical skew panels. For isotropic panels, it is found that the value Pcr initially increases with an increase in the skew angle and later decreases as the skew angle increases beyond 15°. For laminated composite panels, the Pcr value decreases as the aspect ratio increases for all laminate stacking sequences.

A New Shape of Snaked-Lay Pipeline

2011 ◽  
Vol 250-253 ◽  
pp. 2829-2832
Author(s):  
Yu Xiao Liu ◽  
Tao Ge ◽  
Xin Li ◽  
Jing Zhou
Keyword(s):  
Finite Element ◽  
Nonlinear Finite Element ◽  
Buckling Load ◽  
Lateral Buckling ◽  
Critical Buckling Load ◽  
Post Buckling ◽  
The Moment

Snaked-lay pipeline is an effective method for control lateral buckling of pipeline, which is used widely. For design of snaked-lay pipeline the key is how to control lateral buckling of pipeline, namely, the lateral buckling is triggered at the designed location, the moment and strain of post buckling are acceptable. A new shape of snaked-lay pipeline is presented. Based on ANSYS, nonlinear finite element of pipeline is built. Comparisons show that the critical buckling load, moment and strain of post-buckling are all reduced for the new shape of snaked-lay pipeline.

The Study on the Effect of the Lateral Braces on the out-of-Plane Stability of Web Openings Circular Steel Arches

2014 ◽  
Vol 501-504 ◽  
pp. 624-627
Author(s):  
Li Yun Jiang ◽  
Ming Li ◽  
Sen Hao Yang
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Large Deformation ◽  
Buckling Load ◽  
Elastic Buckling ◽  
Radial Load ◽  
Buckling Mode ◽  
Web Openings ◽  
Research Results ◽  
Out Of Plane

The paper adopts large deformation elastic buckling finite element method, researches the out-of-plane stability of lateral braced web openings circular steel arches under the distributed radial load and considers the effects of rise-span ratio, arch foot condition, brace rigidity and brace quantity. Research results demonstrate that the out-of-plane buckling load of web openings circular arches increases with the rise of rise-span ratio and increases with the improvement of arch foot constraint. Buckling half waves increase gradually with the increase of lateral brace stiffness. When brace stiffness reaches the brace critical stiffness, the out-of-plane buckling load of steel arches increases will no longer increase with the rise of the brace stiffness, and the buckling mode of steel arches will transit from out-of-plane instability to in-plane instability. The improvement degree of lateral brace to the bucking load of web openings circular steel arches depends on the lateral brace quantity and the size of the brace intervals.

Sign in / Sign up

Export Citation Format

Share Document