Energy Absorption and Deformation Modes of Thin PVC Tubes Internally Grooved When Subjected to Axial Plastic Collapse

1989 ◽  
Vol 203 (1) ◽  
pp. 1-8 ◽  
Author(s):  
A G Mamalis ◽  
D E Manolakos ◽  
G L Viegelahn ◽  
W Johnson
Keyword(s):  
Failure Modes ◽  
Experimental Investigations ◽  
Collapse Mechanism ◽  
Plastic Collapse ◽  
Constant Depth ◽  
The Mean ◽  
Thin Walled ◽  
Energy Absorbing ◽  
Deformation Modes ◽  
Good Agreement

Theoretical and experimental investigations into the quasi-static plastic collapse of thin-walled PVC tubes containing a number of geometrical discontinuities in the form of internal axial grooves of constant depth, with the aim of providing information about its behaviour as an energy-absorbing device, are reported. An inextensional collapse mechanism for folding the shell in a non-symmetrical diamond fold mode, taking into account stationary, circumferential, inclined and travelling plastic hinges, is considered. The failure modes and the mean postbuckling load necessary to perform the operation are discussed. Predicted results based on the collapse modes encountered, when compared with those obtained experimentally were found to be in good agreement.

scholarly journals Structural behaviour of composite slab with high performance concretes

2021 ◽  
Author(s):  
Haile Mengistu
Keyword(s):  
High Performance ◽  
Failure Modes ◽  
Experimental Investigations ◽  
Structural Behaviour ◽  
Interface Shear ◽  
Composite Slab ◽  
Composite Slabs ◽  
Energy Absorbing ◽  
Steel Deck ◽  
Bond Characteristics

Composite slabs with profiled steel deck and concrete toping have gained wide acceptance as they lead to faster, lighter and economical construction. Extensive research works have been conducted on the behaviour of composite slabs to study their structural behavior and steel-concrete interface shear bond resistance which primarily governs the failure. However, the use of emerging highly durable engineered cementitous composite (ECC) in composite slab is new and no research has been conducted yet. High strain hardening and intrinsic crack width characteristics of ECC can significantly improve structural performance of composite slabs through enhancing ductility, energy absorbing capacity and steel-concrete shear bond. In this study, experimental investigations are conducted to evaluate the shear bond characteristics of composite slabs made with ECC and conventional self-consolidating concrete (SCC) using Code based m-k method. Twelve slab specimens having variable shear span and two types of profiled steel deck were tested under four point loading. The performance of ECC and SCC composite slabs are compered based on load-deflection response, stress-strain development in concrete and steel, failure modes, energy absorbing capacity and steel-concrete shear bond parameters (m and k) and bond stress.

scholarly journals Behaviour of composite framed shear wall system

2021 ◽  
Author(s):  
Muhammad Akram
Keyword(s):  
Shear Strength ◽  
Failure Modes ◽  
Shear Wall ◽  
Steel Tube ◽  
Analytical Models ◽  
Experimental Investigations ◽  
Concrete Core ◽  
Deformation Response ◽  
Energy Absorbing ◽  
Wall System

This research investigated the behaviour of a novel form of composite framed shear wall system (CFSWS) under lateral loading. The CFSWS consisted of a composite wall (made of two skins of profiled steel sheeting and an infill of concrete) connected to pinned steel or fixed concrete filled steel tube (CFST) frame. The experimental investigations on one and two-storey four CFSWS models of 1/6th scale provided information on shear load-deformation response, shear strength/stiffness, energy absorbing capacity, stress-strain characteristics and failure modes. The failure of CFSWS was associated with buckling of steel sheets and development of diagonal concrete core cracking as well as the wall-frame fastener and CFST frame joint failure. Overall, the failure was governed by wall failure rather than frame. Analytical models for the shear strength of CFSWS were developed and found to be in close agreement with experiments. This research confirmed the viability of using novel CFSWS in practical construction.

Energy-Absorbing Characteristics of the Stiffened Thin-Walled Tubes Subjected to Axial Crushing

2013 ◽  
Vol 437 ◽  
pp. 158-163
Author(s):  
Wei Liang Dai ◽  
Xu Guang Li ◽  
Qing Chun Wang
Keyword(s):  
Energy Absorption ◽  
Specific Energy ◽  
Absorption Capacity ◽  
Test Results ◽  
Energy Absorption Capacity ◽  
Specific Energy Absorption ◽  
Axial Crushing ◽  
The Mean ◽  
Thin Walled ◽  
Energy Absorbing

Energy absorbing characteristics of the non-stiffened and stiffened single hat sections subjected to quasi-static axial crushing were experimentally investigated. First non-stiffened hat sections were axially crushed, then structures with different stiffened methods (stiffened in hat and stiffened in the plate) were tested, finally energy absorption capacities of these structures were compared. Test results showed that, for the appropriate designed stiffened tube, the mean crush force and mass specific energy absorption were increased significantly compared to the non-stiffened. Stiffened in hat section showed a little more energy absorption capacity than that stiffened in the plate, but the structure may sustain a global bending.

Energy Absorption of Axial Members With the Inclusion of Functionally Graded Cellular Structure

2015 ◽  
Author(s):  
Muhammad Ali ◽  
Khairul Alam ◽  
Eboreime Ohioma
Keyword(s):  
Energy Absorption ◽  
Cellular Structure ◽  
Tube Wall ◽  
Axial Loading ◽  
Hybrid Structure ◽  
Functionally Graded ◽  
Shell Elements ◽  
Thin Walled ◽  
Energy Absorbing ◽  
Deformation Modes

Axial members are commonly used in automotive structures and are responsible for absorbing significant portion of impact energy in the event of an accident. This study was conducted to investigate the effects of inclusion of functionally graded cellular structures in thin walled members under compressive axial loading. A compact functionally graded cellular structure was introduced inside a 352 mm long square tube with side length and wall thickness of 74 mm and 3.048 mm, respectively. The tube wall material was aluminum. The cellular structure’s geometry was observed in the cross-section of a banana peel that has a specific graded cellular packing in a confined space. This packing enables the peel to protect the internal soft core from external impacts. The same cellular pattern was used to construct the structure in present study. The study was conducted using non-linear finite element analysis in ABAQUS. The hybrid structure (tube and graded cellular structure) was fixed on one side and on the other (free end) side, was struck by a rigid mass of 300 Kg travelling at a velocity of 35 mph (15.64 m/s) along the axis of the square tube and perpendicular to the in-plane direction of the graded cellular structure. The tube and cell walls were discretized using reduced integration, hourglass control, 4 nodes, and hexahedral shell elements. The impact plate was modeled with 4 node rigid shell elements. General contact conditions were applied to define surface interaction among graded structure, square tube, and rigid plate. The parameters governing the energy absorbing characteristics such as deformation or collapsing modes, crushing/ reactive force, and energy curves, were evaluated. The results showed that the inclusion of graded cellular structure increased the energy absorption capacity of the square tube by 41.06%. The graded structure underwent progressive stepwise, layer by layer, crushing mode and provided lateral stability to the square tube thus delaying local tube wall collapse and promoting outward convex localized folds on the tube’s periphery as compared to highly localized and compact deformation modes that are typically observed in an empty square tube under axial compressive loading. The variation in deformation mode, large contact areas, presence of graded cellular structure resulted in enhanced stiffness of the hybrid structure, and therefore, high energy absorption by the structure. The results of this preliminary study show a potential of functionally graded cellular materials to significantly improve the energy absorbing capacities of thin walled members under axial loading by altering member’s crushing deformation modes.

scholarly journals Structural behaviour of composite slab with high performance concretes

2021 ◽  
Author(s):  
Haile Mengistu
Keyword(s):  
High Performance ◽  
Failure Modes ◽  
Experimental Investigations ◽  
Structural Behaviour ◽  
Interface Shear ◽  
Composite Slab ◽  
Composite Slabs ◽  
Energy Absorbing ◽  
Steel Deck ◽  
Bond Characteristics

Composite slabs with profiled steel deck and concrete toping have gained wide acceptance as they lead to faster, lighter and economical construction. Extensive research works have been conducted on the behaviour of composite slabs to study their structural behavior and steel-concrete interface shear bond resistance which primarily governs the failure. However, the use of emerging highly durable engineered cementitous composite (ECC) in composite slab is new and no research has been conducted yet. High strain hardening and intrinsic crack width characteristics of ECC can significantly improve structural performance of composite slabs through enhancing ductility, energy absorbing capacity and steel-concrete shear bond. In this study, experimental investigations are conducted to evaluate the shear bond characteristics of composite slabs made with ECC and conventional self-consolidating concrete (SCC) using Code based m-k method. Twelve slab specimens having variable shear span and two types of profiled steel deck were tested under four point loading. The performance of ECC and SCC composite slabs are compered based on load-deflection response, stress-strain development in concrete and steel, failure modes, energy absorbing capacity and steel-concrete shear bond parameters (m and k) and bond stress.

scholarly journals Design and Numerical Simulation of Pyramidal Prefolded Patterned Thin-Walled Tubes

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Junxian Zhou ◽  
Chuang Dong ◽  
Bingzhi Chen ◽  
Xu Niu
Keyword(s):  
Energy Absorption ◽  
High Performance ◽  
Geometric Analysis ◽  
Deformation Mode ◽  
Absorption Efficiency ◽  
Energy Absorption Efficiency ◽  
Thin Walled ◽  
Comparative Results ◽  
Energy Absorbing ◽  
Deformation Modes

An improved pyramidal prefolded pattern was designed and applied to thin-walled tubes. This delicately designed pattern modularizes the tube to control the folding process and act as an inducer to trigger deformation modes with outstanding crushing performance. Dynamic crushing tests were conducted numerically; the simulation results reveal that the patterned square tube developed a deformation mode with shorter wavelength, better load consistencies, and higher energy-absorption efficiency (up to 29%) than that of the traditional counterpart. Moreover, geometric analysis was performed and structural improvements were conducted by applying the optimal geometric parameters onto an octagonal profile. The designed patterned octagonal tube collapsed into a highly efficient deformation mode known as diamond mode. Furthermore, the comparative results show that patterned octagonal tubes demonstrated an energy absorption up to 90.1% higher than that of a conventional square column while improving the geometric compliance. These findings enrich research on patterned tubes and provide new explorations for the development of high-performance energy-absorbing structures.

Plastic Collapse Analysis of Slender Circular Tubes Subjected to Large Deformation Pure Bending

2002 ◽  
Vol 5 (4) ◽  
pp. 241-257 ◽  
Author(s):  
Mohamed Elchalakani ◽  
Raphael Grzebieta ◽  
Xiao-Ling Zhao
Keyword(s):  
Large Deformation ◽  
Plastic Material ◽  
Kinematic Model ◽  
Deformation Energy ◽  
Collapse Mechanism ◽  
Plastic Collapse ◽  
Pure Bending ◽  
External Work ◽  
Plastic Mechanism ◽  
Thin Walled

This paper presents a plastic mechanism analysis for thin-walled circular hollow section (CHS) tubes deforming in a multi-lobe or diamond collapse mode under large deformation pure bending. The fold formation process was such that the shell curvature flattened on the compression side transforming into a definite number of flat triangles attached to each other. The collapse proceeded progressively by folding about the base and sides of these triangular planes and over traveling hinge lines. The collapse mechanism was similar to the diamond crush mode. An existing kinematic model for an axially compressed thin-walled circular tube was modified to predict the collapse curve of a thin-walled tube under bending. Inextensional deformation and rigid plastic material behaviour were assumed in the derivation of the deformation energy. Ovalisation was observed during the test and its deformation energy was determined and found significant. An expression for the plastic collapse moment was obtained by equating the total energy absorbed in bending, rolling and ovalisation to the external work carried out during a given cycle of deformation. Comparisons of the predicted post-buckling moments and slopes of the collapse curves with those obtained from experiments carried out by the authors on cold-formed circular hollow sections show very good agreement.

A Study on Bending Behaviours of Aluminium Foam-Filled Tubes

2014 ◽  
Vol 620 ◽  
pp. 413-416 ◽  
Author(s):  
Yang An ◽  
Chun Hui Yang ◽  
Peter Hodgson
Keyword(s):  
Failure Modes ◽  
Aluminium Foam ◽  
Strengthening Effect ◽  
The Finite Element Method ◽  
Bending Tests ◽  
Bending Load ◽  
Foam Filled ◽  
Thin Walled ◽  
Energy Absorbing ◽  
Insight Into

In the study, the strengthening effect of aluminium foam in thin-walled aluminium tubes subject to bending load in investigated experimentally and numerically. Bending tests are conducted on foam filler, hollow tube and foam-filled tube. The finite element method is used as well to get deeper insight into the crush failure modes via focusing on the influence from wall thickness of the tube. The obtained information is useful to optimally design foam-filled tubes as energy absorbing devices in automotive engineering. The optimisation results can be implemented to find an optimum foam-filled tube that absorbs the same energy as the optimal hollow tube but with much less weight.

scholarly journals Axial Crushing Behaviors of Thin-Walled Corrugated and Circular Tubes - A Comparative Study

2017 ◽  
Vol 14 (1) ◽  
pp. 5-10 ◽  
Author(s):  
Mohd. Reyaz-Ur-Rahim ◽  
P. K. Bharti ◽  
Afaque Umer
Keyword(s):  
Numerical Models ◽  
Good Alternative ◽  
Collapse Mechanism ◽  
Element Analysis ◽  
Circular Tubes ◽  
Thin Walled Structures ◽  
Crushing Force ◽  
Thin Walled ◽  
Collapse Behavior ◽  
Energy Absorbing

Abstract With the help of finite element analysis, this research paper deals with the energy absorption and collapse behavior with different corrugated section geometries of hollow tubes made of aluminum alloy 6060-T4. Literature available experimental data were used to validate the numerical models of the structures investigated. Based on the results available for symmetric crushing of circular tubes, models were developed to investigate corrugated thin-walled structures behavior. To study the collapse mechanism and energy absorbing ability in axial compression, the simulation was carried in ABAQUS /EXPLICIT code. In the simulation part, specimens were prepared and axially crushed to one-fourth length of the tube and the energy diagram of crushing force versus axial displacement is shown. The effect of various parameters such as pitch, mean diameter, corrugation, amplitude, the thickness is demonstrated with the help of diagrams. The overall result shows that the corrugated section geometry could be a good alternative to the conventional tubes.

Forming of Stringer Sheets with Solid Tools

2016 ◽  
Vol 1140 ◽  
pp. 3-10 ◽  
Author(s):  
Stefan Köhler ◽  
Peter Groche ◽  
Alexander Baron ◽  
Maximilian Schuchard
Keyword(s):  
Failure Modes ◽  
Sheet Thickness ◽  
Experimental Investigations ◽  
Sheet Metal Parts ◽  
Flat Sheet ◽  
Bending Process ◽  
Analytical Estimation ◽  
Bending Radius ◽  
The Common ◽  
Good Agreement

Stringer sheets are bifurcated parts that possess, compared to flat sheet metal parts, a higher stiffness due to their higher geometrical moment of inertia. Currently, the common way of forming spatially curved stringer sheets is hydroforming. This article shows the feasibility of forming stringer sheets by using solid tools with short process times, which is more relevant for the industrial application. A die-bending process with a slot in the punch for the stringer is investigated. Since buckling of the stringer is one of the occurring failure modes, depending on the stringer height, an analytical estimation of the critical stringer height is carried out while considering the bending angle, bending radius and sheet thickness. The subsequent numerical and experimental investigations show a good agreement with the analytical estimation. Finally, a stiffness test is carried out with stringer sheets of different stringer heights. The result of this test underlines the motivation of forming buckling-free stringer sheets with stringers as high as possible. The normalized stiffness increases with rising stringer height until buckling occurs. At this point the stiffness values begin to fall with growing stringer height.

Sign in / Sign up

Export Citation Format

Share Document