Parabolic Arch SE 110.16

Parabolic Arch

Type: SE 110.16
Name: Parabolic Arch
Technical Description

  Parabolic arches are popular elements in construction engineering. They can be employed as bridges or beams for example. Normally these bridges are statically indeterminate. The special feature of the parabolic arch is that in the arch only normal forces and bending moments occur, but no shear forces. That is the case when the arch is subjected to a uniform distributed load and both ends are mounted in fixed bearings. This enables arches to be constructed from loosely set stones – a construction technique which has been in existence for many centuries. Loads acting upon the inner of the arch are primarily compressive forces in the direction of the normal force at every point of the arch.

  SE 110.16 includes a pre-shaped parabolic arch. It can be subjected to point or distributed loads. It is possible to suspend an elastic roadway and load it.

  One of the arch’s bearings is fixed, the other is horizontally moevable bearing. Weights are used to undo this movement. The movable bearing thus becomes a fixed bearing. Additional weights compensate for the vertical bearing reaction.

  Dial gauges record the deflection of the arch under load and the horizontal displacement of the movable bearing. As long as the roller bearing is movable, the arch is statically determinate, though it is substantially deformed under load. As soon as the roller bearing becomes immovable, the arch is no longer statically determinate and is deformed only to a minor degree.

  All the component elements of the experiment are clearly laid-out and housed securely in a storage system. The complete experimental setup is arranged in the frame SE 112.


Learning Objectives / Experiments

- mechanical principles of the parabolic arch
- differences between statically determinate and
  statically indeterminate arches
- measurement of the deformations of the arch under
- measurement of the bearing reactions on the
  statically indeterminate arch under load
- calculation of the bearing reactions
- influence of load on reaction forces and deformation

  of the arch

  * point load

  * distributed load

  * suspended elastic roadway under load

* Statically determinate or statically indeterminate
  parabolic arch under load1
* Deformations of the arch under load1
* Bearing reactions of the arch
Available accessories
SE 112 -- Mounting Frame
Alternative products
SE 110.12 -- Lines of Influence on the Gerber Beam
SE 110.17 -- Three-Hinged Arch 
SE 110.18 -- Forces on a Suspension Bridge

[1] investigation of a parabolic arch, optionally statically determinate (1 fixed bearing, 1 movable bearing) or indeterminate (2 fixed bearings)
[2] loading of the arch with a distributed load by way of 7 evenly distributed loads or by point loads or by suspended roadway with loads
[3] 2 dial gauges record the deformation of the arch under load
[4] weights to compensate for the reactions of a fixed bearing
[5] roadway with 1 set of shackles to be suspended into the arch; shackles in graduated length

[6] storage system to house the components

[7] experimental setup in frame SE 112

Technical Data

Parabolically pre-shaped steel arch
- length: 1000mm
- height: 280mm
- cross-section: 20x6mm

Roadway made of PVC

- dead-weight: approx. 2,6N

LxWxH: 900x70x3mm
Dial gauge
Measuring range: 0...25mm, graduations: 0,01mm
- 11x 1N (7+4 hangers)
- 7x 1N (shackles)

- 36x 1N
- 19x 5N

Dimensions and Weight

LxWxH: 1170x480x178mm (storage system)

Weight: approx. 38kg (total)

Scope of Delivery

1 arch with 7 shackles + 7 hangers
1 roadway with shackles

1 set of weights
2 deflection rollers with fixture
1 bearing
2 dial gauges
1 storage system with foam inlay
1 set of instructional material

Order Details

022.11016  SE 110.16  Parabolic Arch