Structures - Plastic Bending of Beams

This kit allows students to utilise the aluminium beam or steel beam to understand the elastic and plastic properties of simply supported beam, fixed or encastre beam and propped cantilever beam. This kit has a LCD display will show the value of applied load and this kit has a maximum load capacity of 50 kg so the user should stop applying load when the LCD shows reading exceeds 50 kg.

Each of the two supports can be transformed into simply support or fixed support. There is one fixed support on the left-hand side can be moved hozitontally. Beam can be bent under 3 fixing methods to form simply supported beam (when both supports are just simply supported), fixed or encastre beam (when both supports are fixed), and propped cantilever beam (when the left-hand side support is fixed, and right-hand side support is simply supported).

This kit consists of a Safety Tube which should be always screwed-in to cover the exposed threaded rod during operating this equipment. This Safety Tube is meant to protect the users from the risk in the event of the mating thread of the screw jack mechanism is partially or completely failed, which will cause serious injury or death.

Student can apply load by carefully turning the handle of the screw jack and record the deflection by the number of rotations. Student must keep any body part away from the moving elements to avoid finger crush in the danger zone. This kit includes a set of beam specimens for comparison of the elastic and plastic properties.  Student can also calculate the yield working load and collapsed load and use these predicted values to compare with the experimental results. The concepts that student will learn are materials properties such as Elastic Modulus, yield stress, second moment of area, collapse load, plastic moments, plastic hinges and shape factor.

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

Learning Objectives

• Force acting as point load when:

              - Deflection is increasing at elastic and plastic region.

              - Beam is bent under 3 types of supports:

                            - Simply supported beam.

                            - Fixed or encastre beam. (One Fixed Support can move horizontally)

                            - Propped cantilever beam.

- Material of a beam is different. (Aluminium or Steel)

- Profile of a beam is different.

• Material Properties, e.g. Elastic Modulus (Young’s Modulus, E), Yield Stress
• Second moment of area (I)
• Collapse Load
• Plastic Moments
• Plastic Hinges
• Shape Factor
• Observe the shape of collapsed beam under 3 types of supports.
• Comparison of predicted results vs experimental results.