Structures - Simple Suspension Bridge

This kit allows students to apply concentrated loads or uniformly distributed load (UDL) on the bridge deck of the two types of simple suspension bridge in parabolic shape to explore tensions of the cable at both ends.

By sliding down the guided pulley support on the left-hand side of the tower and using the thumb nut to lock it into position, this kit allows the students to swap between a bridge that with two guided pulley supports at same height level and a bridge that with two guided pulley supports at different height level.

There are 2 load cells connected to each of the 2 LCD displays. These 2 load cells are used to measure the tensions of each of the two types of the bridge at both two ends. This allows the students to explore and measure the tensions at both ends when loading scenarios are different. For example, students can move the concentrated load across the span of the bridge and the load cell will show the tension measured at both ends. Students can also apply UDL for full span on the bridge deck. This allows the students to calculate the theoretical tension forces at both ends and compare these values with the experimental values. This will reinforce their knowledge in shift of centre of gravity (CoG), principles of moments, equilibrium equations for finding the tensions by resolving vertical forces and horizontal forces.

Construction is made in 2mm mild steel, providing a strong and stiff base to perform experiments on.

Learning Objectives

• Tension of cable at both ends when:

           -          the position of concentrated load is varying.

           -          the type of loads is different. (UDL or concentrated load)

           -         the mass of loads is increasing.

           - the type of simple suspension bridge is different.  (symmetrical or asymmetrical)

• Shift of Centre of Gravity (CoG)
• Principle of Moments.
• Equilibrium Equations.
• Comparison of theoretical tensions vs experimental tensions.