Features
Articulated beam with two cantilever beams and a suspended beam as an example of a typical bridge
Direct indication of reactions
Lines of influence for different load cases
Many bridges are executed as Gerber beams. Bridges are subjected to moving loads. Consequently, it is important to take these moving loads into account in the design process. To that end, the so called lines of influence are determined. Lines of influence describe static reactions to a moving load, such as the internal reactions of the beam or support reactions. The lines of influence are determined by way of method of sections and the conditions of equilibrium, in the same way as the bending moment diagram for a static load for example.
A Gerber beam is an articulated beam, in the case of Tesca Stress on Gerber Beam with two cantilever beams and a suspended beam between them. Two bearings support each cantilever beam. The suspended beam is mounted on articulated supports on each of the cantilever beam arms. As a result the entire beam is statically determinate.
The cantilever beam supports are equipped with force gauges which indicate the support reactions.
Single weights and a moving load are provided to place load on the beam. This means the beam can be subjected to point or distributed loads, or to a moving load. The force gauges indicate the effect of a moving load directly in the support reactions. The supports are movable.
All the component elements of the experiment are clearly laid-out and housed securely in a storage system. The complete experimental set-up is arranged in the frame.
The well-structured instructional material sets out the fundamentals and provides a step-by- step guide through the experiments.

Specifications
Investigation of the lines of influence in a statically determinate Gerber beam under different loading
Gerber beam comprising 2 cantilever beams and 1 suspended beam
Suspended  beam  mounted  by  articulated supports on cantilever beams
Beam subjected to moving load or loaded down by single weights
4 movable supports with force gauge
Storage system to house the components
Experimental set-up in frame

Technical Specifications
Beam
Total length: 1220mm
Cantilever beam length: 503mm
Suspended beam length: 250mm
Force gauge: -50...+50N
Weights
-  24x 5N
-  12x 1N
Moving load: 10+20N

Experiment Possibilities
Familiarization with a Gerber beam
Application of the method of sections and the conditions of equilibrium to calculate the support forces for
Point load
Distributed load
Moving load
Determination of the internal reactions under static load
Shear force curve
Bending moment diagram
Determination of the lines of influence under moving load
Comparison of the calculated and measured reactions for static and moving load

Scope of Delivery
Gerber beam (2 cantilever beams + 1 suspended beam)
4 supports with force gauge
1 moving load
1 set of weights
1 storage system with foam inlay
1 set of instructional material