HTML isn't really used for this anymore, it's done via CSS (Cascading Style Sheets). On the web currently, HTML pretty much just describes what to be displayed, CSS describes how it's to be displayed and JavaScript is used to provide function to a web page.
In HTML, you could use: align="center" as an attribute of the img tag to center it. Now it's preferable to use text-align: center CSS for the object containing the image (a div or p).
Positioning things on top of each other brings in z-axis and position CSS. Check out the CSS tutorial at http://www.w3schools.com . It's free.
MOHR-COULOMB FAILURE CRITERIA:
In 1900, MOHR-COULOMB states Theory of Rupture in Materials which defines as “A material fails due to because of a critical combination of normal and shear stress, not from maximum normal or shear stress”. Failure Envelope is approached by a linear relationship.
If you can not understand the below symbols see the attachment below
f f ()
Where: f = Shear Stress on Failure Plane
´= Normal Stress on Failure Plane
See the graph in the attachment
For calculating the shear stress, when Normal stress, cohesion and angle of internal friction are given. Use this formula: shear stress = f c tan
Where,
• f is Shear Stress on Failure Plane
• c is Cohesion
• is Normal Total Stress on Failure Plane
• is Friction Angle
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