Mohr's Arbelos and Lamé's Ellipsoids

Initializing live version
Download to Desktop

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

Mohr's arbelos and Lamé's ellipsoids are two representations of the stress state at any point of a continuum. These give a geometric interpretation of the stress vector as a function of the direction of the normal to the infinitesimal facet across which this stress is exchanged.


This Demonstration helps with understanding the relationship between Mohr's arbelos and Lamé's ellipsoids by viewing a synchronous animation in which the stress vector changes with the direction of the normal.


Contributed by: Maurizio Brocato (February 2020)
Open content licensed under CC BY-NC-SA



The black arrow represents the normal vector (a symbolic representation of the material facet normal to is also shown). The purple arrow represents the stress vector ; the dashed red arrow represents the component of in the direction of ; the dashed blue arrow represents the component of orthogonal to .

More information about the example can be found in [1].


[1] M. Brocato, Cours de mécanique des structures. Volume 1. Poutres élastiques, Paris: Presses des Ponts, forthcoming.

Feedback (field required)
Email (field required) Name
Occupation Organization
Note: Your message & contact information may be shared with the author of any specific Demonstration for which you give feedback.