Hook_s_Law - Hooks Law MECH320- Spring 08 Prepared by:...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Hook’s Law MECH320- Spring 08 Prepared by: Nasser-Eddin M., PhD
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 Table of contents ± Basic Stress-Strain Relations ± Isotropy ± Isotropic Pressure ± ± Pure Shear ± Uniaxial Stress ± Relations of Mat'l Constant ± Summary
Background image of page 2
3 Basic stress-strain relations
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
4 Basic stress-strain relations
Background image of page 4
5 Basic stress-strain relations
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
6 Basic stress-strain relations In a mathematical sense, we can assume that stress and strain are related in some functional fashion as shown. Determining the appropriate function to use, however, is a formidable task, since every material will have its own behavior, and this behavior can be very complicated. As long as we restrict ourselves to modest loads, however, most materials used by engineers exhibit quite simple behavior: elastic and linear. We have already discussed the concept of elastic versus plastic behavior; we now consider linearity. In simple terms this means that stress = strain * factor. For our general stress and strain descriptions, the picture is more complicated.
Background image of page 6
7 Basic stress-strain relations
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
8 Basic stress-strain relations Since there are six stress components and six strain components, it would take 36 coefficients to relate an arbitrary stress state to the corresponding strain. Six of these constants are shown above. Fortunately, most materials do not require such a complex set of factors. In fact, we will see that more often than not we only need 2 coefficients.
Background image of page 8
9 Isotropic Material The important feature a material must have in order to allow a 2-parameter characterization is isotropy . This means it exhibits the same behavior in all directions. For example if we were to take specimens from the block …in several different orientations, and then test each sample…
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Isotopic material …we would observe the same behavior for each specimen. (For a material like wood, this would not be the case; such materials are called anisotropic .). As we are about to see, an important
Background image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 65

Hook_s_Law - Hooks Law MECH320- Spring 08 Prepared by:...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online