compression stress limit in concrete

[joncle10]

Hi, I am currently checking an inclined reinforced concrete walls which is supporting 4 floors (angle of 80degreees - the wall is braced by the slab at each level); the software I am using does not give an integrated force for inclined shapes.
Thus I am checking the compression stresses of the wall (along with other verifications) and would like to verify that it is not exceeded. I am not very familiar with the strut and tie method.
What is the compression concrete limit (function of f´c) to which I should stick ? The code I am using is ACI318-11.

Thank you for the help

 

[BAretired]

The wall can be designed as a compression member having both axial force and moment obtained from a frame analysis. Somewhere in the structural system, the horizontal forces from the loads acting on the sloping wall must be resisted by something other than the wall. The 80[sup]o[/sup] slope has no bearing on the permissible compression stress.

BA