Mohr's Circle Calculator | 2D Stress Transformation Tool for Engineers

Free online Mohr's Circle calculator for 2D stress analysis. Calculate principal stresses, maximum shear stress, and visualize stress transformations instantly. Essential tool for mechanical and civil engineers


Stress Components (MPa)

Material Properties

Advanced Analysis Options
Auto-updating

Stress Transformation

45° 90° 135° 180°

Mohr's Circle Analysis Results

Input Stresses: σx = 15 MPa, σy = 5 MPa, τxy = 4 MPa
Safety Factor: Safe
Parameter Value Unit Notes
Maximum Principal Stress (σ1) 0 MPa Maximum normal stress
Minimum Principal Stress (σ2) 0 MPa Minimum normal stress
Angle for σ1 Direction (θσ1) 0 degrees Orientation of maximum principal stress
Angle for σ2 Direction (θσ2) 0 degrees Orientation of minimum principal stress
Maximum Shear Stress (τmax) 0 MPa Maximum shear stress
Center of Mohr's Circle (σavg) 0 MPa Average normal stress
Radius of Mohr's Circle (R) 0 MPa Radius of Mohr's circle
Von Mises Equivalent Stress 0 MPa Based on distortion energy theory
Factor of Safety 0 - Based on selected failure criterion
Note: Calculations follow standard Mohr's Circle transformation equations. Principal stresses are the eigenvalues of the stress tensor. Angles are measured counterclockwise from the x-axis.
Mohr's Circle Visualization
Zoom: 100%
Stress State Summary
0 MPa
Max Principal Stress
0 MPa
Min Principal Stress
0 MPa
Max Shear Stress
0
Safety Factor
Design Guidelines
  • Principal stresses represent the maximum and minimum normal stresses
  • Maximum shear stress occurs at 45° to principal planes
  • For ductile materials, use Von Mises criterion for yield prediction
  • For brittle materials, use Maximum Principal Stress criterion
Stress Element Visualization
Stress Distribution
Failure Criteria Comparison

Understanding Mohr's Circle: A Powerful Tool for Stress Analysis

Mohr's Circle Diagram Explained

Visual representation of Mohr's Circle for stress transformation

Mohr's Circle is an essential graphical technique that every mechanical and civil engineer should master. Developed by Christian Otto Mohr in 1882, this powerful method simplifies complex stress transformation calculations and provides intuitive visual insights into stress states at different orientations.

What Exactly is Mohr's Circle?

Mohr's Circle is a two-dimensional graphical representation of the transformation equations for plane stress. It allows engineers to:

  • Determine principal stresses (σ₁ and σ₂) quickly
  • Calculate maximum shear stresses (τmax)
  • Find stress components at any orientation angle
  • Visualize the relationship between normal and shear stresses
  • Understand stress states without complex calculations

Practical Applications in Engineering

Mohr's Circle isn't just academic - it's used daily in these real-world scenarios:

1. Structural Engineering

When analyzing beams, columns, and connections, engineers use Mohr's Circle to:

  • Determine critical stress combinations
  • Identify potential failure planes
  • Calculate safety factors against yielding

2. Mechanical Design

Machine component designers rely on Mohr's Circle for:

  • Shaft and pressure vessel analysis
  • Gear tooth stress evaluation
  • Bearing and connection design

Pro Tip

While our calculator handles the math, we recommend all engineering students learn to draw Mohr's Circle manually. This builds fundamental understanding that helps when interpreting computer analysis results.

Frequently Asked Questions

Principal stresses (σ₁ and σ₂) are the maximum and minimum normal stresses that occur on planes with zero shear stress. The maximum shear stress (τmax) occurs on planes rotated 45° from the principal planes and equals half the difference between the principal stresses.

While Mohr's Circle is primarily for 2D stress states, three circles can represent principal stresses in 3D (Mohr's Circles for three dimensions). However, our calculator focuses on the more common 2D plane stress case.