The article aims to find the buckling loads for pinned-rotationally
restrained shallow circular arches in terms of the rotational end stiffness,
geometry and material distribution. The loading is a concentrated vertical
force placed at the crown. A geometrically nonlinear model is presented
which relates not only the axial force but also the bending moment to the
membrane strain. The nonlinear load-strain relationship is established
between the strain and load parameters. This equation is then solved and
evaluated analytically. It turns out that the stiffness of the end-restraint
has, in general, a significant effect on the lowest buckling load. At the
same time, some geometries are not affected by this. As the stiffness
becomes zero, the arch is pinned-pinned and as the stiffness tends to
infinity, the arch behaves as if it were pinned-fixed and has the best
load-bearing abilities.