The conventional triaxial compression for Westerly granite test indicates: CP = 100 MPa, USC = 201 MPa, reference: Haimson and Chang (2000).
you can find more in the following reference:
Strength criterion for rocks under compressive-tensile stresses and its application, Journal of Rock Mechanics and Geotechnical Engineering, Volume 7, Issue 4, August 2015, Pages 434-439, https://doi.org/10.1016/j.jrmge.2015.05.002
You can find it from the following link:
Article Strength Criterion for rocks under compressive-tensile stres...