In a method of constructing a supporting structure (e.g. of a bridge or the roof of a building) in arched form, an initially straight or pre-curved frame structure, having a first end and a second end opposite to the first end, is pivotally supported at the first and second ends, whereupon the first and second ends are pushed towards one another to achieve a displacement of the first and second ends relative to one another, where the reduction of the distance between the first and second ends causes them to pivot and the frame structure to progressively and flexibly bend, against its resiliency, into a final arched form, the displacement of the first and second ends relative to one another is chosen to amount to at least 1% of the initial distance between the first and second ends, where the first and second ends are then fixed relative to one another in their displaced position so as to preserve the final arched form of the frame structure.