In construction engineering, a distinction is made between beams and arches. An arch is a statically indeterminate supported structure with a curved axis and two fixed supports or clamp fixings. The supports of an arch (such as a double-articulated arch) absorb forces vertically and horizontally. The ends of the arch in the supports do not move. This produces the static arching effect of the system. In mechanical engineering, crane hooks and chain links are typical examples of a curved beam.
This experiment includes three different beams, borne on statically determinate supports: a circular beam, a semi-circular beam and a quadrant beam. The beam under test is loaded with weights. Dial gauges record its horizontal and vertical deformations. All three beams have the same cross-section and so the same second moment of area. This enables test results to be directly compared. Simi-circular and circular beams are fixed to a support on the pillar. The quadrant beam is clamped into a support block.