Design of a Variable Stiffness Wrist Brace With an Origami Structural Element

2018 ◽  
Author(s):  
Marcos B. Oliveira ◽  
Chang Liu ◽  
Mengtao Zhao ◽  
Samuel M. Felton
Keyword(s):  
Analytical Model ◽  
Variable Stiffness ◽  
Structural Element ◽  
Bending Tests ◽  
Three Point Bending ◽  
Plate Structure ◽  
Flat Shape ◽  
Flexural Hinges

This paper presents a motor driven wrist brace that can adjust its stiffness by changing its mesoscale geometry. The design involves a plate structure that folds from a flexible flat shape to a stiff corrugated shape by means of a motor driven tendon. The structure is built using a laminate of rigid and flexible layers, with embedded flexural hinges that allow it to fold. The paper proposes a simplified analytical model to predict stiffness, and physical three-point bending tests indicate that the brace can increase its stiffness up to fifty times by folding.

scholarly journals On the Evaluation of the Mechanical Behaviour of Structural Glass Elements

2006 ◽  
Vol 514-516 ◽  
pp. 799-803 ◽  
Author(s):  
Sandra Costa ◽  
Micaela Miranda ◽  
Humberto Varum ◽  
Filipe Teixeira Dias
Keyword(s):  
Mechanical Behaviour ◽  
State Of The Art ◽  
Building Construction ◽  
Structural Glass ◽  
Tempered Glass ◽  
Structural Element ◽  
Bending Tests ◽  
Three Point Bending ◽  
Structural Applications ◽  
Strength And Stiffness

Glass can be considered to be a high-technology engineering material with a multifunctional potential for structural applications. However, the conventional approach to the use of glass is often based only on its properties of transparency and isolation. It is thus highly appropriate and necessary to study the mechanical behaviour of this material and to develop adequate methods and models leading to its characterisation. It is evident that the great potential of growth for structural glass applications is an important opportunity of development for the glass industry and the building/construction sectors. The work presented in this paper is a reflection of this conclusion. The authors shortly present the state-of-the-art on the application of glass as a structural element in building and construction, and refer to other potential fields of application and available glass materials. The experimental procedures and methods adopted in three-point bending tests performed on 500 × 100 [mm2] float, laminated and tempered glass specimens with thicknesses between 4 and 19 mm are thoroughly described. The authors evaluated the mechanical strength and stiffness of glass for structural applications. This work contributes to a deeper knowledge of the properties of this material.

Investigation of the Deformation Twins on the Bending Cross Section of TA2 Titanium Sheet

2020 ◽  
Vol 837 ◽  
pp. 41-45
Author(s):  
Shuai Sun ◽  
Kai Hua Liu
Keyword(s):  
Electron Backscatter Diffraction ◽  
Testing Machine ◽  
Pure Titanium ◽  
Titanium Sheet ◽  
Bending Tests ◽  
Three Point Bending ◽  
Deformation Twins ◽  
Ebsd Technique ◽  
Backscatter Diffraction ◽  
Deformation Area

In order to determine the evolution features of deformation twins for TA2 commercial pure titanium (cp-TA2), the TA2 samples were bent under different bending angles in three-point bending tests via a universal testing machine. The electron backscatter diffraction (EBSD) technique was applied to identify the grain boundaries (GBs) and twin boundaries (TBs) in the bending areas. The results reveal that the type of deformation area would effect the evolution of different deformation twins. It is inferred that the state of stress would promote the multiplication of the same type of deformation twins.

scholarly journals A Study of the Flexural Behavior of Fiber-Reinforced Concretes Exposed to Moderate Temperatures

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3522
Author(s):  
Marta Caballero-Jorna ◽  
Marta Roig-Flores ◽  
Pedro Serna
Keyword(s):  
Steel Fiber ◽  
Flexural Behavior ◽  
Polypropylene Fibers ◽  
Fiber Reinforced ◽  
Insulation System ◽  
Bending Tests ◽  
Synthetic Fibers ◽  
Three Point Bending ◽  
Lower Performance ◽  
Cracked Specimens

The use of synthetic fibers in fiber-reinforced concretes (FRCs) is often avoided due to the mistrust of lower performance at changing temperatures. This work examines the effect of moderate temperatures on the flexural strengths of FRCs. Two types of polypropylene fibers were tested, and one steel fiber was employed as a reference. Three-point bending tests were carried out following an adapted methodology based on the standard EN 14651. This adapted procedure included an insulation system that allowed the assessment of FRC flexural behavior after being exposed for two months at temperatures of 5, 20, 35 and 50 °C. In addition, the interaction of temperature with a pre-cracked state was also analyzed. To do this, several specimens were pre-cracked to 0.5 mm after 28 days and conditioned in their respective temperature until testing. The findings suggest that this range of moderate temperatures did not degrade the behavior of FRCs to a great extent since the analysis of variances showed that temperature is not always a significant factor; however, it did have an influence on the pre-cracked specimens at 35 and 50 °C.

Utilization of Dacite as Alternative Aggregate in Asphalt Mixture

2012 ◽  
Vol 509 ◽  
pp. 209-214
Author(s):  
Shao Peng Wu ◽  
Pan Pan ◽  
Ming Yu Chen
Keyword(s):  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Major Objective ◽  
Widespread Application ◽  
Bending Tests ◽  
Three Point Bending ◽  
Large Numbers ◽  
Asphalt Content ◽  
The Cost ◽  
Cost Of Construction

With the widespread application of asphalt mixture, current demand from transportation managers for construction and maintenance of their pavement network consumes large numbers of aggregates. If agencies excessively favor to some certain kinds of excellent aggregates, the cost of construction could be considerably expensive. The major objective of this study is to determine the feasibility of utilizing dacite in asphalt mixtures. By means of Marshall, freeze-thaw, rutting and three-point bending tests, the performances of dacite and basalt asphalt mixture are compared. The results of the testing illustrate that dacite asphalt mixture is more susceptible to gradation and asphalt content than basalt asphalt mixture. Meanwhile it is showed that the performances of dacite asphalt mixture can be improved greatly with the involvement of additives including active mineral powder and cement. Furthermore, it is validated that dacite can be used as alternative aggregate in asphalt mixture.

Evaluation of Young’s modulus of RE123 bulk superconductors by three point bending tests

2006 ◽  
Vol 445-448 ◽  
pp. 422-426 ◽  
Author(s):  
T. Sato ◽  
K. Katagiri ◽  
T. Hokari ◽  
Y. Hatakeyama ◽  
A. Murakami ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Bending Tests ◽  
Three Point Bending ◽  
Bulk Superconductors

scholarly journals Local strain and damage mapping in single trabeculae during three-point bending tests

2011 ◽  
Vol 4 (4) ◽  
pp. 523-534 ◽  
Author(s):  
R. Jungmann ◽  
M.E. Szabo ◽  
G. Schitter ◽  
Raymond Yue-Sing Tang ◽  
D. Vashishth ◽  
...  
Keyword(s):  
Local Strain ◽  
Bending Tests ◽  
Three Point Bending ◽  
Damage Mapping

scholarly journals Acoustic Emission Analysis of Cement Mortar Specimens During Three Point Bending Tests

2016 ◽  
Vol 13 (12) ◽  
pp. 2283-2297 ◽  
Author(s):  
I. Stavrakas ◽  
D. Triantis ◽  
S.K. Kourkoulis ◽  
E.D. Pasiou ◽  
I. Dakanali
Keyword(s):  
Acoustic Emission ◽  
Cement Mortar ◽  
Emission Analysis ◽  
Bending Tests ◽  
Three Point Bending ◽  
Acoustic Emission Analysis
Sign in / Sign up

Export Citation Format

Share Document