Mohr-Coulomb Failure Analysis of Triaxial Tests on Soil | How to Obtain Cohesion and Friction Angle

Mohr-Coulomb failure criterion is used to determine the strength of soil. This video explains how to use the data from three triaxial tests, draw a Mohr circle for each test, and obtain the failure envelope using the Mohr-Coulomb failure criterion that defines the soil strength such as cohesion and friction angle. These three tests were taken from real experiments and as you will see in this video, they don't match perfectly along the failure envelope line which is pretty common in real practice.
More videos on soil strength:

If you find these videos useful, please share it with your colleagues and subscribe to this channel. More details can be found in my book called Soil Mechanics Through project-based Learning.

[kirtgze]

The main point is how to draw tangent line for three circles. The line is not obtained just with a ruler as you said. Linear regression analysis is required to find best fit line.

[Lewis-pt]

Hello sir, please how do you get the line used to get the angle…

[faithomokhuale]

is c' and phi' not for effective stress though? is this case has pore water pressure been implemented/ considered. how would that differ the solution ?

[emeldahowell]

Is there a theoretical approach to solve this question without actually drawing the move circles?

[roarowwad]

Is the other properties like E, unit wight and dilation angle of this type of of soil mentioned in the book ?
How could I got the book ?

[flxforcrd]

You didn't show how to get cohesion or angle of friction, can you please elaborate on how to get them?

[aftaburrahman]

That's very informative, can i apply this method on rock? Also if i have two axial test can i apply the same method ? Thanks in advance