CALCULATION OF EFFECTIVE ENERGY ABSORPTION RATIO

This paper establishes a Finite Element (FE) model of a rigid barrier impact of a single vehicle constructed from carbon steel, stainless steel, and aluminum alloy, which are three typical materials used in metro vehicle car body structures. The different responses of the three materials during the collision are compared. According to the energy absorption, velocity, deformation and collision force flow characteristics of each vehicle, the relationship between the energy absorption ratio of the vehicle body and the energy absorption ratio of its key components is proposed. Based on the collision force flow distribution proportion of each component, the causes of the key components’ deformation are analysed in detail. The internal relationship between the deformation, energy absorption and impact force of the key components involved in a car body collision is elucidated. By determining the characteristic parameters describing the vehicle’s dynamic stiffness, a metro vehicle frontal impact model using lumped parameters is established that provides a simple and efficient conceptual design method for railway train safety design. These research results can be used to guide the design of railway trains for structural crashworthiness.

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Effects of Fall Height and Impact Strategy on Energy Absorption Ratio Between Shoulder Joint and Elbow Joint

Journal of Medical and Biological Engineering ◽

10.1007/s40846-017-0342-1 ◽

2017 ◽

Vol 38 (3) ◽

pp. 378-386

Author(s):

Paul Pei-Hsi Chou ◽

Shu-Zon Lou ◽

Yen-Po Huang ◽

Hon-Yu Chen ◽

You-Li Chou

Keyword(s):

Energy Absorption ◽

Shoulder Joint ◽

Elbow Joint ◽

Absorption Ratio ◽

Energy Absorption Ratio ◽

Fall Height

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The Dynamic Behavior of Sandwich Plate With Layered Graded Metallic Honeycomb Cores

Volume 9: Prof. Norman Jones Honoring Symposium on Impact Engineering; Prof. Yukio Ueda Honoring Symposium on Idealized Nonlinear Mechanics for Welding and Strength of Structures ◽

10.1115/omae2016-55006 ◽

2016 ◽

Cited By ~ 1

Author(s):

Zhihua Wang ◽

Shiqiang Li ◽

Genwei Wang ◽

Guoyun Lu ◽

Longmao Zhao

Keyword(s):

Energy Absorption ◽

Failure Modes ◽

Sandwich Plate ◽

Impact Resistance ◽

Local Deformation ◽

Military Equipment ◽

Compression Properties ◽

Specific Loading ◽

Honeycomb Cores ◽

Energy Absorption Ratio

Sandwich cellular structure, associated with more excellent mechanical properties and physical characteristic, such as, panel ductility and high core compressibility, is widely used in aerospace, transportation, military equipment and civil infrastructure. Due to the special compression properties of functional graded cores, the graded sandwich structure presented more excellent impact resistance than the ungraded sandwich. This article presents the results of experimental, numerical investigation into the failure mode and dynamic plastic response of layered graded sandwich plate with layered honeycomb cores to air blast loading. The core arrangements (different core density) effects on the structure’s deformation behavior, energy absorption and impact resistance were mainly discussed. Three typical failure modes can be observed, that was, local deformation, global bending and penetration failure. Under specific loading conditions, the graded sandwich had more excellent impact resistant and energy absorption ratio, especially for the density-decreased core arrangement sandwich.

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Energy Absorption of Thin-Walled Beams with a Pre-Folded Origami Pattern

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.566.569 ◽

2014 ◽

Vol 566 ◽

pp. 569-574 ◽

Cited By ~ 1

Author(s):

Jia Yao Ma ◽

Zhong You

Keyword(s):

Energy Absorption ◽

Cross Sections ◽

Longitudinal Direction ◽

Peak Force ◽

Plastic Hinges ◽

Novel Structure ◽

Collapse Mode ◽

Transport Vehicle ◽

Thin Walled ◽

Energy Absorption Ratio

The bumper beam of a transport vehicle conventionally is commonly made from thin-walled materials with a shallow curved profile, with either opened or closed cross sections. Upon lateral crushing, it fails in a bending collapse mode characteristic of formation of a limited number of plastic hinges along the beam. This paper presents a novel structure known as the origami beam. It is a thin-walled shallow curved beam of square cross section whose surface is pre-folded according to an origami pattern. The origami pattern serves as a mode inducer to trigger a collapse mode that is more efficient in terms of energy absorption. Numerical simulation of the beam subjected to quasi-static lateral loading shows that a new collapse mode, referred to as the longitudinal folding mode featuring shortening of beam in the longitudinal direction prior to the formation of plastic hinges, can be triggered by the pre-folded origami pattern, leading to higher energy absorption and lower peak force than those of conventional ones. An increase in specific energy absorption (ratio between energy absorption and weight of the structure) of 23.6% being achieved in an optimum case, while the peak force is also reduced by 12.9%. Our work demonstrates that applying origami patterns to shallow curved thin-walled beams can effectively induce new collapse modes on the structures and increase the energy absorption capability.

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