In reinforced concrete columns under biaxial bending, the compression zone ideally follows a parabolic shape. However, calculating this exact profile is complex. To simplify design while maintaining safety, Eurocode 2 (EN 1992-1-1, Section 3.1.7(3)) introduces an easy approximation. The compression zone is bounded by two limits along the breadth (αδb) and height (αδh) and runs parallel to the neutral axis. This boundary is positioned at 0.8 times the distance from the extreme compression fibre to the neutral axis, with the factor λ = 0.8 directly specified in the code.