Maximum shear stress on a given plane?

[physicsdumby]

I want to know the maximum shear stress acting on the y-z face(plane). I already know all 6 stress components: Sxx, Syy, Szz, Sxy, Syz, Sxz. The shear components on the y-z face are Sxy and Sxz, which are orthogonal to each other. Is the maximum shear on this plane simply the greater of the two, or is there one more transformation needed?

 

[Chestermiller]

I want to know the maximum shear stress acting on the y-z face(plane). I already know all 6 stress components: Sxx, Syy, Szz, Sxy, Syz, Sxz. The shear components on the y-z face are Sxy and Sxz, which are orthogonal to each other. Is the maximum shear on this plane simply the greater of the two, or is there one more transformation needed?

Neither. It's the resultant of S_xy and S_xz.

Chet