Strain gauges are widely used across all engineering fields to measure mechanical deformation of a solid object. The most common type of strain gauges consists of a patterned metal foil on a stiff plastic backing sheet glued to the solid object. Deformation in the object leads to deformation in the foil, thereby causing its electrical resistance to change. The fractional change in resistance, ΔR/R0, is related to the mechanical strain by the gauge factor (GF): GF = (ΔR/R0)/ε. The GF for metallic foils are typically between 2 to 5 , due mostly to changes in length and cross-sectional area. Compared to metallic foils, semiconductor devices can exhibit much larger GF due to piezoresistive effects  where the resistivity changes rapidly with strain due to the dependence of the bandgap on inter-atomic spacing. For example, the gauge factor of p-type  single crystalline silicon can be as high as 200 . As a result, for precision measurements, semiconductor gauges, also called piezoresistors, are preferred over metal foils. These types of devices are widely used as ‘hard’ sensors attached to stiff materials such as metals, concretes and high modulus plastics for structural health monitoring or quantifying specimen deformation.
Published ASAP, Nano Letters (2013)
I want to define node-based-surface in Python script to use it in *tie card. Please help. Thank you
please , can you help me getting links to download free material library ?
Is there some good data base for materials dedicated to FEA ?
Thank you for any help.
Ying Li, Wylie Stroberg, Tae-Rin Lee, Han Sung Kim, Han Man, Dean Ho, Paolo Decuzzi, Wing Kam Liu
The Uniaxial Tensile Response of Porous and Microcracked Ceramic Materials
Amit Pandey,§,*,†,‡ Amit Shyam,§,* Thomas R. Watkins,§,* Edgar Lara-Curzio,§,** Randy J. Stafford,¶,* and Kevin J. Hemker||
Is there a free/open-source mesher for the Spectral Element Method?
I know some researchers use a conventional mesher with order 3 elements
and then include more nodes in the meshes (but without improve the
Thanks in advance,
Doese any one have a working MATLAB code for paticle splitting methods? I have used Monte carlo simulations, Subset simulations etc in the past and am
wanting a more effecient code.
Thanks in advance,
How to find a response for a pinned-(pinned+ torsion spring) column with sinusoidal axial load?
I am unable to decouple the equations in space and time using variable separable method, with one end pinned-other end pinned with torsion spring as boundary conditions.
Can anyone please help.
I use abaqus S4R shell element to simulate the pipe bending. How to out the total bending moment at the cross-section?
I am trying to run a job for a very high resolution mesh. This job is taking many hours so I decided to allow it to run overnight. However, after about 6 hours, the job terminates due to exceeding the CPU time limit. Is there a way to set the CPU time limit to unlimited? Or are there any other workarounds that may allow me to run the job?
A numerical study of elastic bodies that are described by constitutive equations that exhibit limited strainsSubmitted by Alejandro Ortiz... on Mon, 2013-11-25 19:36.
Recently, a very general and novel class of implicit bodies has been developed to describe the elastic response of solids. It contains as a special subclass the classical Cauchy and Green elastic bodies. Within the class of such bodies, one can obtain through a rigorous approximation, constitutive relations for the linearized strain as a nonlinear function of the stress. Such an approximation is not possible within classical theories of Cauchy and Green elasticity, where the process of linearization will only lead to the classical linearized elastic body.
In this paper, we implement the radial basis functions for solving a classical type of time-fractional telegraph equation defined by Caputo sense for (1<α≤2). The presented method which is coupled of the radial basis functions and finite difference scheme achieves the semi-discrete solution. We investigate the stability, convergence and theoretical analysis of the scheme which verify the validity of the proposed method. Numerical results show the simplicity and accuracy of the presented method.
Research Assistant in the Development & Processing of Polymeric Composite Materials via Liquid Resin InfusionSubmitted by Deirdre_Murphy on Mon, 2013-11-25 12:21.
The University of Limerick (UL) with over 13,000 students and 1,300 staff is an energetic and enterprising institution with a proud record of innovation and excellence in education, research and scholarship. The dynamic, entrepreneurial and pioneering values which drive UL’s mission and strategy ensures that we capitalise on local, national and international engagement and connectivity. We are renowned for providing an outstanding student experience and conducting leading edge research. Our commitment is to make a difference by shaping the future through educating and empowering our students.
This paper is on my work at Singapore. I think this paper has the following contributions
(1) A concise flow rule is proposed for concrete, every item in the flow rule has clear physical meaning
(2) Let us know that for any material, the flow rule can be simple, and we don't have to pay attention to the potential funcion.
The reaction of Zr/B multilayers with a 50 nm modulation period has been studied using scanning AC nanocalorimetry at a heating rate of approximately 1,000 K/s. We describe a data reduction algorithm to determine the rate of heat released from the multilayer. Two different exothermic peaks are identified in the nanocalorimetry signal: a shallow peak at low temperature (200 - 650°C) and a sharp peak at elevated temperature (650 - 800°C). TEM observation shows that the first peak corresponds to heterogeneous inter-diffusion and amorphization of Zr and B, while the second peak is due to the crystallization of the amorphous Zr/B alloy to form ZrB2.
Phase field modeling of stress-induced tetragonal-to-monoclinic transformation and its effect on transformation tougheningSubmitted by mohsenzaeem on Fri, 2013-11-22 23:02.
Phys.Chem. Chem. Phys., 2013, 15, 20786
As the 6th issue of Advances in Mechanics is going to publish, i post one of the review paper in this issue to share with all of you! Hope it will be helpful to you!
Journal Tittle: Advances in Mechanics
Article Tittle: A brief survey on discontinous Galerkin methods in computational fluid dynamics
Author: Chi-Wang Shu(Brown University)
Article published in Journal of the Mechanics and Physics of Solids
Superconvergent second derivative recovery technique and its application in a nonlocal damage mechanics modelSubmitted by Xiaoge Gan on Thu, 2013-11-21 22:23.
What are the possible methods to observe dislocations in a material? Which one is better?
thank you in advance..