A classical
Gerber beam — two cantilevers carrying a suspended centre span through articulated bearings — assembled on the
ST500 digital frame. The structure is statically determinate, so support forces, shear and bending moment follow directly from equilibrium and can be compared against live measurements from the
ST501 instrumented supports. Each cantilever has two possible support positions, and the roadway accepts loads at thirteen positions, which makes this the natural stand for teaching
influence lines of continuous bridge beams under moving loads.
