Beams Curved in Plan

Introduction Beams curved in plan are used to support curved floors in buildings, balconies, curved ramps and halls, circular reservoirs, and similar structures. In a curved beam, the center of gravity of the loads acting normal to the plane of curvature lies outside the line joining its supports. This situation develops torsional moments in the beam, in addition to bending moments and shearing forces. To maintain the stability of the beam against overturning, the supports must be fixed or continuous. In the case of circular beams supported by symmetrically placed columns, the vertical reactions are provided by the columns and due to the symmetry, the torsional moments at the center of the curved beam between any two consecutive supports will be zero. Also the maximum negative bending moment develops at the support sections and positive maximum bending moment at sections in between the supports.