Experiment for the study of the vertical and horizontal defl ection of diff erent unsymmetrical sections. Mounts on the Structures platform and connects to the Structures automatic data acquisition unit and software (VDAS® Onboard).
Key Features
• One of a range of experiment modules that teach structures principles
• Fits to the Structures platform for ergonomic use and space-saving storage
• Includes specimen beams of three diff erent cross-sectional shapes for increased experiment range
• Two diff erent study areas in one product: shear centre and bending
• High-resolution indicators for accurate measurements
• Supplied with a storage tray to keep smaller items safe
• Includes Vernier caliper to allow measurement of cross-section
• Works with user-friendly software (VDAS®)
Description
One of a range of experiment modules that fi t to the Structures platform (STS1, available separately), the product helps students understand symmetrical and non-symmetrical bending of three diff erent beam shapes, including an equal ‘L’, a ‘U’ and rectangular. It also fi nds the shear centre of the channel (‘U’) beam.
For the symmetrical and non-symmetrical tests, a chuck clamps a beam while allowing rotation on its axis and allowing loads to be applied at various angles. Load applied at the free end produce resulting defl ections, measured by a pair of precision indicators. Students plot their results on a Mohr’s circle which allows them to fi nd the experimental Principal Second Moments of Area and position of the principal axes. These may be compared to those for the arbitrary section axes and the values calculated by textbook beam equations. This helps to confi rm the reliability of the textbook equations and the accuracy of the experiment results.
For shear centre tests, a chuck clamps the ‘U’ section beam. A plate clamped to the free end allows various off set loads to twist the beam. Students apply loads at various off sets and use the indicators to determine when the twist is zero, thus corresponding to the shear centre position.
This product includes a Vernier caliper for accurate measurements of the beam cross-sections.
The defl ection indicators have their own displays, but they can connect to the USB interface nub of the Structures platform for computer display and data acquisition (VDAS® Onboard).
Learning outcomes
• Show that shear centre can be outside beam section boundaries
• Shear centre of an unsymmetrical section
• Horizontal and vertical defl ection in symmetrical and unsymmetrical sections at diff erent loads and load angles
• Using Mohr’s circle to fi nd principal axes and Second Moments of Area
Essential Ancillary
• Structures Platform (STS1)
