Plastic Deformation of Impulsively Loaded Straight Clamped Beams

1965 ◽  
Vol 32 (1) ◽  
pp. 7-10 ◽  
Author(s):  
John S. Humphreys
Keyword(s):  
Plastic Deformation ◽  
Beam Theory ◽  
Upper Bounds ◽  
Impulsive Loading ◽  
Steel Beams ◽  
Rigid Plastic ◽  
First Approximation ◽  
Ballistic Pendulum ◽  
Clamped Beams ◽  
Flat Steel

A series of tests was conducted on flat steel beams of various sizes and material properties, using sheet explosive to provide sufficiently high uniform impulsive loading to produce significant plastic deformation. The beams were attached to a ballistic pendulum for measurement of applied impulse, and were photographed with a Fastax camera during deformation. The resulting final deformations are compared with the rigid-plastic theory of Symonds and Mentel, which is seen to give upper bounds that are in general higher by about 20–30 percent than the deformations observed. A fairly good first approximation to maximum deflection for engineering purposes is in fact obtained simply by using rigid-plastic beam theory (including axial constraints).

Inelastic failure of fully clamped beams and circular plates under impact loading

2002 ◽  
Vol 216 (2) ◽  
pp. 133-149 ◽  
Author(s):  
N Jones ◽  
C Jones
Keyword(s):  
Impact Loading ◽  
Elementary Theory ◽  
Threshold Energy ◽  
Steel Beams ◽  
Circular Plates ◽  
Rigid Plastic ◽  
Threshold Conditions ◽  
Clamped Beams ◽  
Impact Energies ◽  
The Impact

An experimental investigation is reported on the impact loading of fully clamped mild steel beams and circular plates struck by relatively heavy masses. The impact energies are sufficient in some tests to cause material failure and, thus, to provide the threshold conditions for cracking and severance for impact velocities up to 6.74m/s for beams and 15.66m/s for plates. The beams were struck at several locations across the span, and a significant reduction in the threshold energy is observed for strikes near to a support. Round-nosed impactors require more energy to induce failures than flat-nosed ones. Furthermore, they cause failure to develop at the supports of both beams and plates rather than initiating rupture at the impact point, which is the case for a blunt striker. Reasonable agreement is obtained between the predictions of an elementary theory, which uses rigid-plastic methods of analysis, and the experimental results for the deflection and failure of beams struck at the mid-span. The experimental data, which include static and dynamic material properties, are suitable for calibrating numerical schemes and for further study on the accuracy of criteria for the dynamic inelastic failure of structures.

Impact With Finite Acceleration Time of Elastic and Elastic-Plastic Beams

1956 ◽  
Vol 23 (3) ◽  
pp. 411-415
Author(s):  
R. C. Alverson
Keyword(s):  
Plastic Deformation ◽  
Cross Section ◽  
Plastic Hinge ◽  
Small Time ◽  
Steel Beams ◽  
Time Interval ◽  
Transverse Impact ◽  
Rigid Plastic ◽  
Elastic Plastic ◽  
Small Time Interval

Abstract The purpose of the work described in this paper was to provide information on the elastic and plastic deformation of steel beams subjected to transverse impact. The particular impact problem treated was chosen to correspond to conditions in tests in which a beam initially at rest is struck by a massive hammer, so that a specified change of velocity is imposed at a certain cross section in a small time interval. In the present analysis the initial elastic and subsequent elastic-plastic motions were obtained by methods similar to those used by Bleich and Salvadori (3). As in (3), it is assumed that plastic deformation occurs only at a single stationary plastic hinge (in this case at the struck cross section). Results obtained are compared with those of a “rigid-plastic” solution of the same problem, in which plasticity conditions are correctly taken into account but elastic vibrations are not included.

Rigid-Plastic Beams Under Uniformly Distributed Impulses

1965 ◽  
Vol 32 (3) ◽  
pp. 481-488 ◽  
Author(s):  
A. L. Florence ◽  
R. D. Firth
Keyword(s):  
Plastic Deformation ◽  
Strain Hardening ◽  
Large Deflections ◽  
Rigid Plastic ◽  
Clamped Beams ◽  
Plastic Theory

This paper contains the description and results of experiments in which pinned and clamped beams are subjected to uniformly distributed impulses large enough to cause considerable plastic deformation. The final permanent shapes are compared with those predicted by the rigid-plastic theory. They are also compared with the shapes predicted when the theory takes some account of large deflections and strain-hardening.

Experimental and Theoretical Investigation of the Plastic Deformation of Cantilever Beams Subjected to Impulsive Loading

1962 ◽  
Vol 29 (4) ◽  
pp. 719-728 ◽  
Author(s):  
S. R. Bodner ◽  
P. S. Symonds
Keyword(s):  
Plastic Deformation ◽  
Aluminum Alloy ◽  
Strain Rate ◽  
Yield Stress ◽  
Impulsive Loading ◽  
Cantilever Beams ◽  
Rigid Plastic ◽  
Impulsive Load ◽  
Velocity Change ◽  
Plastic Theory

The experimental techniques and the results obtained in a program to evaluate the assumptions of dynamic, rigid-plastic theory of beams are presented. The experiments used steel and aluminum-alloy cantilever beams subjected to either a rapid velocity change at the base or to an impulsive load at the tip. A rigid-plastic theory that includes the strain-rate dependence of the yield stress and geometry changes is outlined for the case of the tip impulsive loading. The predictions of this theory are in satisfactory agreement with the experimental results.

Study of the Titanium Alloy Deformation Behavior in Equal Channel Angular Extrusion

2007 ◽  
Vol 345-346 ◽  
pp. 177-180 ◽  
Author(s):  
Dyi Cheng Chen ◽  
Yi Ju Li ◽  
Gow Yi Tzou
Keyword(s):  
Plastic Deformation ◽  
Titanium Alloy ◽  
Deformation Behavior ◽  
Equal Channel Angular Extrusion ◽  
Effective Strain ◽  
Processing Conditions ◽  
Rigid Plastic ◽  
Die Geometry ◽  
Extrusion Processing ◽  
Plastic Deformation Behavior

The shear plastic deformation behavior of a material during equal channel angular (ECA) extrusion is governed primarily by the die geometry, the material properties, and the processing conditions. Using commercial DEFORMTM 2D rigid-plastic finite element code, this study investigates the plastic deformation behavior of Ti-6Al-4V titanium alloy during 1- and 2-turn ECA extrusion processing in dies containing right-angle turns. The simulations investigate the distributions of the billet mesh, effective stress and effective strain under various processing conditions. The respective influences of the channel curvatures in the inner and outer regions of the channel corner are systematically examined. The numerical results provide valuable insights into the shear plastic deformation behavior of Ti-6Al-4V titanium alloy during ECA extrusion.

scholarly journals Bearing capacity calculation of reinforced concrete corbels under the shear action

2018 ◽  
Vol 230 ◽  
pp. 02005 ◽  
Author(s):  
Oksana Dovzhenko ◽  
Volodymyr Pohribnyi ◽  
Volodymyr Pents ◽  
Dmytro Mariukha
Keyword(s):  
Plastic Deformation ◽  
Reinforced Concrete ◽  
Plasticity Theory ◽  
Inclined Crack ◽  
Ultimate State ◽  
Rigid Plastic ◽  
Characteristic Lines ◽  
Capacity Calculation ◽  
Theory Use ◽  
Concrete Elements

The necessity of creating a general methodology for concrete and reinforced concrete elements strength calculation under the shear is established. Three failure cases of reinforced concrete corbels under the shear are considered. The solutions of problems of corbels strength with failure along the whole section, close to the normal, in the compressed zone under an inclined crack and within the compressed inclined strip are given. A variational method in the plasticity theory, the virtual velocities principle and the characteristic lines method are used for concrete and reinforced concrete elements calculations. In the ultimate state, concrete is considered as a rigid-plastic body. The shear is realized in case when the plastic deformation is localized in the compressed zone. The calculating ultimate load results for different failure cases are given. Such a design scheme is implemented, in which the console strength is minimal. This corresponds to the minimum of power of plastic deformation in concrete compressed zone. Reinforced concrete corbels calculation engineering methods are offered. The elements obtaining effective constructive decisions direction based on the plasticity theory use is determined.

An Investigation into Optimized Ti-6Al-4V Titanium Alloy Equal Channel Angular Extrusion Process

2013 ◽  
Vol 479-480 ◽  
pp. 181-186 ◽  
Author(s):  
Dyi Cheng Chen ◽  
Yi Ju Li ◽  
Gow Yi Tzou
Keyword(s):  
Plastic Deformation ◽  
Titanium Alloy ◽  
Deformation Behavior ◽  
Equal Channel Angular Extrusion ◽  
Extrusion Process ◽  
Process Conditions ◽  
Rigid Plastic ◽  
Die Geometry ◽  
Plastic Deformation Behavior ◽  
Internal Angle

The shear plastic deformation behavior of a material during equal channel angular (ECA) extrusion is governed primarily by the die geometry, the material properties, and the process conditions. This paper employs the rigid-plastic finite element (FE) to investigate the plastic deformation behavior of Ti-6Al-4V titanium alloy during ECA extrusion processing. Under various ECA extrusion conditions, the FE analysis investigates the damage factor distribution, the effective stress-strain distribution, and the die load at the exit. The relative influences of the internal angle between the two die channels, the friction factors, the titanium alloy temperature and the strain rate of billet are systematically examined. In addition, the Taguchi method is employed to optimize the ECA process parameters. The simulation results confirm the effectiveness of this robust design methodology in optimizing the ECA processing of the current Ti-6Al-4V titanium alloy.

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