Hi everyone,

I didn't find any reference or literature with detailed examples about how I have to consider axial force in order to obtain moment-curvature diagrams by hand (without any computational program). Moment-curvature diagrams for beams are easy to elaborate because axial force is null, but when I started to analize the vertical equilibrium on columns (first part on the procedure) I realize that axial force could have two different positions: on compression zone and on tensile zone. I supossed that when axial force is on tensile zone (as shown in left figure), it has to be consider as a vertical force with a vertical direction against gravity, and when axial force is on compression zone (as shown in rigth figure), its direction has to be the same as gravity. Maybe I am wrong and axial force has to be always considered as parallel to gravity direction because columns in mayority of cases work in compression. The second part is about moment calculation and I don't have any problem here.

I supposed that axial force was applied on column center of gravity, without any excentricity problems.

I will aprecciate any help.

Thanks.

Jose Ruiz Esquivel