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.

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.

The Investigation of Significance of the Geometrical Nonlinearity for 1-D Crack Stress Intensity Factor Calculation in Slightly Distorted Thin-Walled Pressurized Pipe

2015 ◽  
Author(s):  
Igor Orynyak ◽  
Andrii Oryniak
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Cross Section ◽  
Crack Depth ◽  
Geometrical Nonlinearity ◽  
Circumferential Stress ◽  
Thickness Ratio ◽  
Inner Pressure ◽  
Thin Walled

The consideration of a geometrical nonlinearity is a common practice for the thin-walled structures. The relevance here are two well-known cases treated in ASME codes. First one is accounting for reduction of the pipe bends flexibility due to the inner pressure. The second one is the retarded increasing (and subsequent saturation) of additional local bending stress with increasing of inner pressure in a pipe with initial cross section form distortion. In both cases the rerounding effect and decreasing of local flexibilities take place. The crack can be treated as the concentrated flexibility and it is quite natural to expect that the stress intensity factor should grow nonlinearly with applied load. Two cases of SIF calculation for 1-D long axial surface crack in a pipe loaded by inner pressure are considered here: a) cross section has an ideal circular form: b) the form has a small distortion and crack is located in the place of maximal additional bending stresses. The theoretical analysis is based on: a) the well known crack compliance method [1] and b) analytical linearized solution obtained for deformation of the curved beam in case of action of fixed circumferential stress due to pressure written in the form convenient for transfer matrix method application. It was shown that for moderately deep crack (crack depth to the wall thickness ratio is 0.5 and bigger) and typical dimensions of pipes used for oil and gas transportation (radius to thickness ratio is 25–40) and loading which can reach up to 200 to 300 MPa, the effect investigated can be quite noticeable and can lead to 5–15 percent reduction of calculated SIF as compared with linear calculation. The analytical results are supported by nonlinear FEM calculation.

Experimental and Numerical Study of the Energy Absorbed with Various Thickness of Thin Rectangular and Square Sections

2012 ◽  
Vol 229-231 ◽  
pp. 1120-1124
Author(s):  
Sajjad Dehghanpour ◽  
Sobhan Dehghanpour
Keyword(s):  
Numerical Analysis ◽  
Energy Absorption ◽  
Cross Section ◽  
Numerical Study ◽  
Rectangular Cross Section ◽  
Lateral Loading ◽  
Thin Walled

Impact is one of very important subjects which always have been considered in mechanical science. Nature of impact is such that which makes its control a hard task. Therefore it is required to present the transfer of impact to other vulnerable part of a structure, when it is necessary, one of the best method of absorbing energy of impact , is by using Thin-walled tubes these tubes collapses under impact and with absorption of energy, it prevents the damage to other parts. Purpose of recent study is to survey the deformation and energy absorption of tubes with different type of cross section (rectangular or square) and with similar volumes, height, mean cross section, and material under loading. Lateral loading of tubes are quasi-static type and beside as numerical analysis, also experimental experiences has been performed to evaluate the accuracy of the results. Results from the surveys is indicates that in a same conditions which mentioned above, samples with square cross section ,absorb more energy compare to rectangular cross section, and also by increscent in thickness, energy absorption would be more.

Buckling Analysis of Double-Limb Lipped Channel Section Member under Axial Load

2011 ◽  
Vol 243-249 ◽  
pp. 268-273
Author(s):  
Qing Ma ◽  
Jin Song Lei ◽  
Wen Zhi Yin
Keyword(s):  
Bearing Capacity ◽  
Axial Load ◽  
Slenderness Ratio ◽  
Ultimate Bearing Capacity ◽  
Thickness Ratio ◽  
Distortional Buckling ◽  
Element Analysis ◽  
Channel Section ◽  
The Finite Element Analysis ◽  
Breadth Ratio

Double-limb lipped channel section steel member is formed by connecting two single limb members with bolts in order to improve the buckling performance. In order to research the buckling form and ultimate bearing capacity of members with different slenderness ratios under axial load, nonlinear analysis of buckling performance is done to this kind of section using the finite element analysis software ANSYS. The influence on bearing capacity caused by height-breadth ratio of section, height-thickness ratio of web and breadth-thickness ratio of flange is analyzed. The results show that: (1) for larger slenderness ratio, complete buckling occurs to the column mainly and the slenderness ratio has larger influence on buckling bearing capacity, while for smaller slenderness ratio, local distortional buckling occurs more; (2) in a certain range, the increase of height-breadth ratio could raise the ultimate bearing capacity of member, but excessive height-breadth ratio would make the ultimate bearing capacity decrease, (3) the increase of both height-thickness ratio and breadth-thickness ratio would decrease the ultimate bearing capacity.

Studying the Critical Buckling Load of FG Beam Using ANSYS

2021 ◽  
Vol 1039 ◽  
pp. 7-22
Author(s):  
Khetam S. Ateah ◽  
Luay S. Alansari
Keyword(s):  
Power Law ◽  
Thermal Load ◽  
Mechanical Load ◽  
Functionally Graded ◽  
Thickness Ratio ◽  
Buckling Load ◽  
Mode Number ◽  
Critical Buckling Load ◽  
Fg Beam ◽  
Power Law Index

In this article, the critical buckling load of functionally graded beam is calculated using ANSYS APDL Software (version 17.2) under mechanical and thermal load. In mechanical load, the effects of length to thickness ratio, power law index and mode number on the non-dimension critical buckling load of fixed-fixed and fixed-free FG beam. The results show that the length to thickness ratio is not effect on the non-dimension critical buckling load while the power law index and mode number effect on the non-dimension critical buckling load. In thermal load, the critical buckling load for fixed-fixed and pinned-pinned FG beam depend on length to thickness ratio, power law index and mode number. The results show that the critical buckling load increases with decreasing length to thickness ratio.

Pretwisted Beams and Columns

1956 ◽  
Vol 23 (2) ◽  
pp. 165-175
Author(s):  
John Zickel
Keyword(s):  
Cross Section ◽  
Buckling Load ◽  
Structural Members ◽  
Moments Of Inertia ◽  
Principal Moments Of Inertia ◽  
Constant Rate ◽  
Thin Walled ◽  
The Cross ◽  
Stiffening Factor

Abstract A theory is developed for the behavior of pretwisted structural members of thin-walled section with slight initial bending. The stresses are at first determined along and perpendicular to the fibers and are then transformed to stresses in the cross section and along the axis. Although the development is perfectly general the integrations are only indicated for doubly symmetric sections. The buckling of doubly symmetric columns which are initially straight but are pretwisted at a constant rate is treated in detail. The results show that columns of decidedly unequal principal moments of inertia can be strengthened up to 90 per cent, but columns of equal moments of inertia are weakened by initial twist. In analogy to the Euler load of the buckling theory for straight, untwisted columns, a reduced Euler load is defined. The buckling load is the product of this reduced Euler load and a stiffening factor.

Simulation of Compress Buckling Performance of Composite Stiffened Panel

2012 ◽  
Vol 184-185 ◽  
pp. 1189-1193
Author(s):  
Qing Shao ◽  
Yu Ting He ◽  
Teng Zhang ◽  
Hai Wei Zhang ◽  
Qing Shan Kang
Keyword(s):  
Cross Section ◽  
Optimization Design ◽  
Engineering Application ◽  
Buckling Load ◽  
Stiffened Panel ◽  
Critical Buckling Load ◽  
Cross Section Area ◽  
Section Area ◽  
Calculation Results ◽  
Composite Stiffened Panel

Finite element method is applied to analyze the buckling performance of composite stiffened panel. Compress buckling critical loads of six types panels with T or Z-section stiffeners are calculated by FEM. The emulational calculation results show that with same cross section area, critical buckling load of panel with T-section stiffeners increases with the reduction of stiffener pitch and the increase of stiffener numbers, while the buckling load of panel with Z-section stiffeners increases to a certain level and then keep almost changeless. To T-section stiffener panels, the relation between thickness of skin and buckling load is approximately quadratic trinominal. Conclusions obtained can offer a referenced measure for the optimization design and engineering application of the structure.

Experimental and finite element studies on buckling of skew plates under uniaxial compression

2015 ◽  
Vol 22 (3) ◽  
pp. 287-296 ◽  
Author(s):  
Srinivasa Chikkol Venkateshappa ◽  
Suresh Yalaburgi Jayadevappa ◽  
Prema Kumar Wooday Puttiah
Keyword(s):  
Finite Element ◽  
Aspect Ratio ◽  
Uniaxial Compression ◽  
Laminated Composite ◽  
Buckling Load ◽  
Element Solution ◽  
Skew Angle ◽  
Critical Buckling Load ◽  
Aluminum 7075 ◽  
Experimental Values

AbstractExperimental studies were made on isotropic skew plates made of aluminum 7075-T6 and laminated composite skew plates under uniaxial compression with unloaded edges completely free and one loaded edge restrained completely and the other loaded edge restrained except translationally in the direction of loading. Experimental values of the buckling load have been determined using five different methods. The buckling load has also been determined using CQUAD8 finite element of MSC/NASTRAN. Comparison is made between the various experimental values of buckling load and the finite element solution. The effects of the skew angle and the aspect ratio on the critical buckling load of isotropic skew plates made of aluminum 7075-T6 have been studied. The effects of the skew angle, aspect ratio, and the laminate stacking sequence on the critical buckling load of laminated composite skew plates have also been studied. The critical buckling load is found to increase with the increase in the skew angle and decrease with the increase in aspect ratio. Method IV yields the highest value for critical buckling load and Method III the lowest value for critical buckling load. Among the various experimental values, the one given by Method IV is closest to the finite element solution, and the discrepancy between them is less than about 5% in the case of isotropic skew plates and about 10–15% in the case of laminated composite skew plates.

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.

scholarly journals Design Buckling Curves for Clamped Orthotropic Laminated Plates

2004 ◽  
Vol 13 (5) ◽  
pp. 096369350401300 ◽  
Author(s):  
Nicholas G. Tsouvalis ◽  
Vassilios J. Papazoglou
Keyword(s):  
Uniaxial Compression ◽  
Pure Shear ◽  
Ritz Method ◽  
Laminated Plates ◽  
Buckling Load ◽  
Orthotropic Plates ◽  
Critical Buckling Load ◽  
Lamination Theory ◽  
Plane Bending

Non-dimensional design buckling curves for clamped rectangular orthotropic plates are presented in this study. These curves provide the critical buckling load of thin, symmetric, cross-ply laminated plates as a function of the laminate's rigidities and aspect ratio for the following seven configurations of the applied in-plane loads: uniform uniaxial compression, triangular uniaxial compression, uniaxial in-plane bending, pure shear, uniform uniaxial compression combined with shear, triangular uniaxial compression combined with shear, and uniaxial in-plane bending combined with shear. Approximate mathematical formulae are also provided. The Classical Lamination Theory, in conjunction with the Rayleigh-Ritz method, has been used for the determination of the critical buckling load. The validity of the study is confirmed by comparing its results with other both theoretical and numerical ones.

Sign in / Sign up

Export Citation Format

Share Document