scholarly journals Experimental Study and Development of Design Formula for Estimating the Ultimate Strength of Curved Plates

2021 ◽  
Vol 11 (5) ◽  
pp. 2379
Author(s):  
Jeong-Hyeon Kim ◽  
Doo-Hwan Park ◽  
Seul-Kee Kim ◽  
Myung-Sung Kim ◽  
Jae-Myung Lee
Keyword(s):  
Aspect Ratio ◽  
Ultimate Strength ◽  
Large Deflection ◽  
Slenderness Ratio ◽  
Compressive Load ◽  
Element Analysis ◽  
Shipbuilding Industry ◽  
Design Formula ◽  
Deflection Analysis ◽  
Collapse Behavior

The curved plate has been extensively used as a structural member in many industrial fields, especially the shipbuilding industry. The present study investigated the ultimate strength and collapse behavior of the simply supported curved plate under a longitudinal compressive load. To do this, experimental apparatuses for evaluating the buckling collapse test of the curved plates was developed. Then, a series of buckling collapse experiments was carried out by considering the flank angle, slenderness ratio, and aspect ratio of plates. To examine the fundamental buckling and collapse behavior of the curved plate, elastoplastic large deflection analysis was performed using the commercial finite element analysis program. On the basis of both the experimental and FE analysis, the effects of the flank angle, slenderness ratio, and aspect ratio on the characteristics of the buckling and collapse behavior of the curved plates are discussed. Finally, the empirical design formula for predicting the ultimate strength of curved plates was derived. The proposed empirical formula is a good indicator for estimating the behavior of the curved plate.

scholarly journals Numerical Investigation on Ultimate Compressive Strength of Welded Stiffened Plates Built by Steel Grades of S235–S390

2019 ◽  
Vol 9 (10) ◽  
pp. 2088 ◽  
Author(s):  
Chenfeng Li ◽  
Sen Dong ◽  
Tingce Wang ◽  
Weijun Xu ◽  
Xueqian Zhou
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Yield Strength ◽  
Ultimate Strength ◽  
Simulation Analysis ◽  
Compressive Load ◽  
Welding Residual Stress ◽  
Stiffened Plates ◽  
Element Analysis ◽  
Collapse Behavior

The welded stiffened plate is widely used in naval architecture and offshore engineering as a basic structural member. The aim of this study is to investigate the effect of welding residual stress and steel grade on the ultimate strength of stiffened plates under uniaxial compressive load by non-linear finite element analysis. Nineteen stiffened plates built with three types of stiffeners with various column slenderness ratios provided in the ISSC’2000 VI.2 benchmark calculations are employed in the present study. The commercial finite element code ABAQUS is applied to simulate the collapse behavior of the stiffened plates and verified against the benchmark calculations. Fabrication-related imperfections, such as initial deflections and residual stresses, are accounted for in the simulations. The ultimate strength of stiffened plates built in common shipbuilding steels, namely S235, S315, S355 and S390, are investigated by varying the yield strength of materials in the simulation. Analysis of the numerical results shows that the welding residual stress reduces the ultimate strength of stiffened plates, and increase in yield strength of the material can effectively improve the ultimate strength of common ship stiffened plates; and quantitative analyses of their influences have also been performed.

PHOTOGRAMMETRY MEASUREMENTS OF INITIAL IMPERFECTIONS FOR THE ULTIMATE STRENGTH ASSESSMENT OF PLATES

2021 ◽  
Vol 156 (A4) ◽  
Author(s):  
A Cubells ◽  
Y Garbatov ◽  
C Guedes Soares
Keyword(s):  
Finite Element ◽  
Ultimate Strength ◽  
Compressive Load ◽  
Initial Imperfection ◽  
Maximum Load ◽  
Surface Shape ◽  
Element Analysis ◽  
Strength Assessment ◽  
Load Carrying ◽  
Geometrical Imperfections

The objective of the present study is to develop a new approach to model the initial geometrical imperfections of ship plates by using Photogrammetry. Based on images, Photogrammetry is able to take measurements of the distortions of plates and to catch the dominant surface shape, including the deformations of the edges. Having this data, it is possible to generate faithful models of plate surface based on third order polynomial functions. Finally, the maximum load- carrying capacity of the plates is analysed by performing a nonlinear finite element analysis using a commercial finite element code. Three un-stiffened and four stiffened plates have been modelled and analysed. For each plate, two initial imperfection models have been generated one, based on photogrammetric measurements and the other, based on the trigonometric Fourier functions. Both models are subjected to the same uniaxial compressive load and boundary conditions in order to study the ultimate strength.

Finite Element Analysis of Longitudinal Bending Collapse of Container Ship Considering Bottom Local Loads

2016 ◽  
Author(s):  
Akira Tatsumi ◽  
Masahiko Fujikubo
Keyword(s):  
Finite Element ◽  
Ultimate Strength ◽  
Container Ship ◽  
Element Analysis ◽  
Local Loads ◽  
Hull Girder ◽  
Longitudinal Bending ◽  
Collapse Behavior ◽  
Large Container ◽  
Collapse Region

The purpose of this research is to clarify the effect of bottom local loads on the hull girder collapse behavior of large container ship (8000TEU class) A 1/2+1+1/2 hold model of container ship is analyzed using implicit finite element method. The results reveal two major causes of reduction of hull girder ultimate strength due to local loads. One is biaxial compressive stresses induced at outer bottom. Thus, smaller hogging moment can induce a collapse of bottom panels. The other is a reduction of effectiveness of inner bottom that is on the tension side of local bending. As a result, the container ship attains hull girder ultimate strength with smaller spread of collapse region compared to that under pure bending.

Ultimate Strength of Dented Narrow Stiffened Panels Subjected to Compressive Loads

2012 ◽  
Author(s):  
Mingcai Xu ◽  
C. Guedes Soares
Keyword(s):  
Ultimate Strength ◽  
Compressive Load ◽  
Tensile Tests ◽  
Nonlinear Fem ◽  
Element Analysis ◽  
Stiffened Panels ◽  
Geometry Model ◽  
The Finite Element Analysis ◽  
Compressive Loads ◽  
Local Dent

This paper investigates the collapse behaviour of stiffened panels with a local dent under axial compressive load. The damage on plates is simulated by quasi-static nonlinear FEM, which accounts for the residual stresses caused by a dent and the springback of the stiffened panels. The material properties used in the finite element analysis have been evaluated by tensile tests. To prescribe appropriate boundary conditions, extended stiffened panels with three bays models are adopted in FE analyses. The resistance of the stiffened panels to denting is analyzed first. The effects of residual stress, geometry model and dent depth of stiffened panels on the ultimate strength and the springback of the stiffened panels are analyzed.

scholarly journals Buckling Behavior and Effective Width Design Method for Thin Plates with Holes under Stress Gradient

2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Yanli Guo ◽  
Xingyou Yao
Keyword(s):  
Aspect Ratio ◽  
Ultimate Strength ◽  
Design Method ◽  
Slenderness Ratio ◽  
Stress Gradient ◽  
Perforated Plate ◽  
Fe Analysis ◽  
Effective Width ◽  
Buckling Behavior ◽  
Buckling Coefficient

This paper aims at investigating the elastic buckling behavior and the effective width method (EWM) to predict the ultimate strength of the simply supported rectangular plates under gradient stress (SSRPSG) with circular or rectangular holes. The analytical models of SSRPSG with circular or rectangular holes were established by using the finite-element (FE) software ABAQUS. The FE parametric study covered the aspect ratio, slenderness ratio, and stress gradients of plate and the dimension and spacing of holes. The FE analysis included eigenvalue buckling analysis and ultimate strength analysis. The eigenvalue results show that the buckling coefficient of the perforated plate gradually decreases, and subsequently, it gradually increases with the increase of the dimension of the hole. The buckling mode changes from the buckling including hole to the buckling of plate strip adjacent to hole at the section of the hole. The increasing stress gradient causes an increasing effect on buckling coefficient. The buckling coefficients are less affected by the aspect ratio and the slenderness ratio of the perforated plate and the spacing of hole when the hole spacing meets a certain limitation. The buckling coefficient equations of the SSRPSG with circular or rectangular holes were developed according to results obtained by FE analysis. Finally, the effective width design method was developed based on FE results and developed buckling coefficient equations. The comparisons on ultimate strength between FE results and the predicted results for SSRPSG with circular and rectangular holes and between the predicted results and test results for perforated columns and beams indicate that the proposed effective width design method is accurate, which can be used to predict the ultimate strength of SSRPSG with circular or rectangular holes.

On Buckling and Ultimate Strength of Perforated Plate Panels under Axial Compression: Experimental and Numerical Investigations with Design Formulations

2008 ◽  
Author(s):  
Ul-Nyeon Kim ◽  
Ick-Heung Choe ◽  
Jeom Kee Paik
Keyword(s):  
Finite Element ◽  
Ultimate Strength ◽  
Steel Plate ◽  
Slenderness Ratio ◽  
Plate Thickness ◽  
Shipbuilding Industry ◽  
Perforated Plates ◽  
Stiffened Panels ◽  
Buckling Strength ◽  
Plate Panels

It has been recognized that the current shipbuilding industry design practice for perforated plates is not relevant with relatively large opening size and/or with large plate thickness, and it is believed that this problem has caused structural damage accidents in actual ship structures with opening. The motive of the present study was initiated to resolve this issue by introducing a new design formulation of the critical buckling strength for perforated plates which is now pertinent to the structural design application at a safety side. For this purpose, a series of experimental and numerical studies are undertaken on buckling and ultimate strength of plates and stiffened panels with an opening and under axial compressive actions. A total of 90 perforated plates and also a total of 9 stiffened panels with an opening are tested until and after the ultimate strength is reached, where important parameters of influence such as the plate aspect ratio, the plate slenderness ratio, the opening size and shape, and the opening location are varied. Elastic-plastic large deflection finite element analyses are performed on the test structures. Existing and newly-derived design formula solutions of buckling and ultimate strength on the test plate panels are compared with experimental results and nonlinear finite element computations, indicating that the critical buckling strength formulation developed in the present study as well as an existing ultimate strength formula is useful for design and strength assessment of steel plate panels with an opening. The experimental database on buckling collapse of steel plate panels with an opening will be very useful for future use. Details of experiments and numerical computations together with insights developed from the present study are documented.

Ultimate Strength and Collapse Behavior of Ring-Stiffened Cylindrical Shells Under External Pressure With Shell Buckling or Stiffener Torsional Buckling

2020 ◽  
Author(s):  
Daisuke Shiomitsu ◽  
Daisuke Yanagihara
Keyword(s):  
Ultimate Strength ◽  
Slenderness Ratio ◽  
Cylindrical Shells ◽  
Deformation Mode ◽  
Initial Deflection ◽  
Localized Deformation ◽  
Torsional Buckling ◽  
Shell Buckling ◽  
Collapse Behavior ◽  
Stiffened Cylindrical Shells

Abstract A series of ultimate strength analyses of ring-stiffened cylindrical shells with various dimensions and scantlings is carried out applying the nonlinear finite element method. The detailed buckling/plastic collapse behavior including the influence of initial deflection applied in the ultimate strength analyses is investigated. In most past studies, detailed classification of collapse modes and investigation of the influence of the initial deflection mode have not been sufficiently conducted. In this study, firstly the ultimate strength analyses of 288 cases varying the dimensions of the ring-stiffened cylindrical shell and the attachment direction of the stiffeners, inside or outside, are performed. From the results, the collapse modes are classified into five modes, which are stiffener-torsional buckling collapse (localized deformation mode and mode to keep strength after the ultimate strength), shell buckling collapse (localized deformation mode and mode with kinking lines), and combined collapse of the buckling modes. A slenderness ratio is proposed using elastic buckling strength and pressure when the circumferential stress reaches the yield stress, and the possibility of estimating the ultimate strength is indicated.

scholarly journals Combined Effects of Geometric and Material Non—linearities on One Dimensional Structural Members

2018 ◽  
Vol 1 (1) ◽  
pp. 5-8
Author(s):  
R.Ramgopal Varma ◽  
G. Venkateswazra Rao
Keyword(s):  
Large Deflection ◽  
Compressive Load ◽  
Linear Analysis ◽  
Combined Effects ◽  
Structural Members ◽  
Axial Compressive Load ◽  
Linear Behavior ◽  
Non Linear ◽  
Deflection Analysis ◽  
Convergence Study

Combined effects of geometric and material non-linearities on a uniform column subjected to an axial compressive load are presented in the present note. A simple, direct iterative numerical method has been proposed to study the geometric and material non-linear behavior of columns subjected to varying boundary conditions. Introduction of material non-linearity in the large deflection analysis of columns subjected to an axial compressive load reveals a reduction in Euler stress obtained when compared to the effect of geometric non-linear analysis and increase in the same when compared to the eflect of material non-linear analysis. A convergence study has been carried outfor the results obtained from the proposed iterative method to prove the efficacy.  

scholarly journals Ultimate strength of square plate with rectangular opening under axial compression

1970 ◽  
Vol 4 (1) ◽  
pp. 15-26 ◽  
Author(s):  
M Suneel Kumar ◽  
P Alagusundaramoorthy ◽  
R Sundaravadivelu
Keyword(s):  
Finite Element ◽  
Ultimate Strength ◽  
Axial Compression ◽  
Slenderness Ratio ◽  
Area Ratio ◽  
Design Equation ◽  
Element Analysis ◽  
Finite Element Software ◽  
Loading Direction ◽  
Square Plate

Unstiffened plates are integral part of ship structures, offshore oil platforms, lock gates and floating docks. Openings are provided in these plates for access and maintenance. Provision of opening influences the ultimate strength of plate elements. In this paper the effect of increase in the size of rectangular opening along the loading direction on the ultimate strength is determined using nonlinear finite element analysis. A general purpose finite element software ANSYS is used for carrying out the study. The software is validated for the ultimate strength of unstiffened plate under axial compression. A parametric study is done for different plate slenderness ratios and by varying the area ratio of opening to plate to determine the effect of ultimate strength on the size of rectangular opening. It is found that increase in area ratio along the loading direction decreases the ultimate strength. The variation in ultimate strength varies linearly for plate slenderness ratio less than 2.23 and varies nonlinearly for plate slenderness ratio beyond 2.23 for area ratio ranging between 0.02 - 0.18. Based on nonlinear regression analysis, a design equation is proposed for square plate with rectangular opening under axial compression. Keywords: Unstiffened Plate, Ultimate Strength, Rectangular Opening, Axial Compression, Design Equation   DOI: 10.3329/jname.v4i1.913 Journal of Naval Architecture and Marine Engineering 4(2007) 15-26

Characteristics of Buckling and Ultimate Strength and Collapse Behaviour of Cylindrically Curved Plates Subjected to Axial Compression

2008 ◽  
Vol 33-37 ◽  
pp. 1195-1200 ◽  
Author(s):  
Joo Shin Park ◽  
Kazuhiro Iijima ◽  
Tetsuya Yao
Keyword(s):  
Ultimate Strength ◽  
Axial Compression ◽  
Numerical Solutions ◽  
Slenderness Ratio ◽  
Axial Loading ◽  
Initial Imperfection ◽  
Least Square Method ◽  
Least Square ◽  
Circular Cylinders ◽  
Collapse Behavior

In the present paper, to clarify and examine the fundamental buckling behaviours of cylindrically curved plates subjected to axial loading, a series of elastic and elasto-plastic large deflection analyses as well as elastic eigen buckling analysis are performed together with the comparisons with the buckling behaviours of circular cylinder. On the basis of the numerical results, the effects of curvature, magnitude of initial imperfection, slenderness ratio and aspect ratio on the characteristics of the buckling and post buckling collapse behavior of cylindrically curved plates and circular cylinders under axial compression are discussed. The buckling strength and ultimate strength formulae of the cylindrically curved plate are empirically derived based on the FEM series analysis by curve fitting using least square method. The validity of the ultimate strength formulations developed in this study has to some extent been verified through comparison with nonlinear numerical solutions.

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