# Mohr-Coulomb Stress Tool In ANSYS Mechanical(Illustrated Expression)

This is an another stress tool in ANSYS Mechanical that you can solve your static problems. There are other theories such as, Maximum Equivalent Stress Tool and Maximum Shear Stress Tool in ANSYS Mechanical. In here, we explain the Mohr-Coulomb Stress theory and how to solve a problem according to this theory.

### What Is Mohr-Coulomb Stress?

In most basic explanation, Mohr-Couloms stress theory is used for brittle materials. For brittle materials, compression stress is also very important parameter for failure as tensile stress. Unlike other theories for ductile materials, compression strength also considered.

Calculation of Mohr-Coulomb stress for brittle materials is very basic. Here is the general formula for Mohr-Coulomb stress.

In this formula, Sigma1 refers to maximum tensile stress that occurs on a specific stress elements on a brittle part or material. Sigma1 is the biggest tensile principal stress value. Sigma2 refers to minimum compresive stress that occur on same stress element on that brittle part. Stensile-limit and Scompressive-limit values are the material’s maximum stress values. As you see above calculation, this equation must be ensured for safety of that part.

Brittle materials can be calculated such as concrete, glass, ceramics etc.