The actual resolution of forces will depend upon the bridge' design.

[1] If no horizontal thrusting forces are generated, this becomes an arch-shaped truss which is essentially a bent beam – see moon bridge for an example.

Such a wood structure uses closely fitted beams pinned together, so the members within the frames are not free to move relative to one another, as they are in a pin-jointed truss structure that allows rotation at the pin joint.

Such rigid structures (which impose bending stresses upon the elements) were further developed in the 20th century as the Vierendeel truss.

This article about a specific type of bridge is a stub.