> For the complete documentation index, see [llms.txt](https://docs.enercalc.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enercalc.com/e3d-user-manual/model-entities/toc161394049/toc161394054.md).

# Internal Stresses

Understand the normal, shear, principal, and Von Mises stresses computed for brick elements.

Three normal stresses σxx, σyy , σzz and three shear stresses σxy, σxz, σyz are computed by the program. They are output at the eight nodes and/or at the center of the element.

The program also outputs principal stresses S1, S2, S3 and the corresponding directional vectors (V1x, V1y, V1z) and (V 3x, V 3y, V 3z). The Von Mises stress, which is often used to estimate the yield of ductile materials, is then computed as follows:

![](https://560001759-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FWNe8U6EBBBdUJHdb2X9G%2Fuploads%2Fgit-blob-49df3e07a7ea93c085d297cbeb504bda1e35cc4c%2Fclip0038.jpg?alt=media)


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