Experiments:

  • Mechanical principles of the parabolic arch.
  • Differences between statically determinate and statically indeterminate arches.
  • Measurement of the deformations of the arch under load.
  • Measurement of the support reactions on the statically indeterminate arch under load.
  • Calculation of the support reactions.
  • Influence of point load or distributed load on reaction forces and deformation of the arch.

Specifications:

  • Investigation of a parabolic arch, optionally statically determinate (1 fixed support, 1 movable support) or indeterminate (2 fixed supports).
  • Loading of the arch with a distributed load by way of 7 evenly distributed weight positions or by point loads.
  • Dial gauges record the deformation of the arch under load.
  • Weights to compensate for the reactions of a fixed support.
  • Storage system to house the components.
  • Experimental set-up in frame.

The main parts of this apparatus are the arch, the point or dispersed load, and the dial gauge. One of the arch’s two ends is fixed, and the other is supported by a roller bearing. The dial gauge’s function is to gauge the arc’s deflection under the horizontal thrust produced by applying loads to the arch. Through hangers that are vertically suspended and spaced equally apart from the arch, loads are applied. Popular design components in construction engineering include parabolic arches. They could be used, for instance, as beams or bridges. These bridges are typically statically uncertain. The unique characteristic of a parabolic arch is the lack of shear forces, just normal forces and bending moments. This is true when both ends of the arch are positioned in fixed bearings and the load is distributed uniformly over the structure. This makes it possible to build arches out of loosely laid stones, a construction method that has been used for many years. At every point along the arch, loads are largely compressive forces acting in the direction of the normal force. SM-1421 includes a pre-shaped parabolic arch. It can be subjected to point or distributed loads. Both of the arch’s supports are on roller bearings, one of which is fixed. This movement can be cancelled using weight sets. This results in the movable support becoming a fixed support. The vertical support reaction is balanced out with additional weight sets. Dial gauges capture the horizontal movement of the moveable bearing and the deflection of the arch under load. The arch is statically determined as long as the roller bearing is movable, despite being significantly distorted when under load. The arch is no longer statically determinate and only slightly deforms when the roller bearing becomes immovable. The experiment’s component parts are all neatly organized and safely stored in a storage system. The frame contains the entire experimental setup. The comprehensive course materials outline the foundations and offer a step-by-step description of the experiments.