I think I got it. Thanks so much for everyone's help and input. Couldn't have done it without you. Attached is the part of the Mathcad sheet that I calculated it. Looks to be correct as best I can tell, but if anyone sees any problems please feel free to let me know. Thanks...
Thanks guys. Trying to build in Mathcad, not do by hand just having trouble finding a good example. Don't do much design these days. I'll check out that adsec software for some guidance.
Quick background on my problem. I'm strengthening a doubly reinforced concrete column subject to combined axial and bending forces using FRP. I have calculated the phiPn and phi Mn necessary to create my P-M Interaction diagram. I need to check that the concrete stress at service load is less...