Chapter 4.7 of the ANSYS 8.1 Theory Manual describes the concrete material model for the
failure of brittle materials, cracking and/or crushing. SOLID65 can be run with the
crushing option turned off (set constant 4 = -1 on the TBDA command for that material).
How does that affect the failure surface as described in the Theory Manual? There are
several terms with fc in the denominator - do they go to 0?
When crushing is removed the failure surfaces are the three orthogonal planes normal to the principal stresses.
If a principal tensile stress exceed the cracking stress of the material a crack will occur parallel to that plane. The
Theory Manual has been modified to clarify this.