The Three-Hinged Arch Unit allows to investigate two statically determinate three-hinged arches (symmetrical or unsymmetrical) that simulate two different types of bridges.
The left hand hinge allows the arch section to rotate and move horizontally. The right hand hinge is held in position although it allows rotational movement of the arch section. The arch under investigation can be loaded using a point load, a uniformly distributed load (by weights) or two moving loads, which simulate a vehicle. The set of weights compensates for the support reactions of the side hinges, thus enabling a comparison between calculated and actual measured values.
The unit includes two long arch segments and one short segment, of which two at a time are connected by a central hinge, producing a symmetrical or unsymmetrical three-hinged arch. The arch segments are easily interchangeable. Moreover, the arch segments have two side hinges at their support, thus creating the three hinges.