BENDING MOMENTS IN A PORTAL FRAME

The experiment hardware fits onto the Structures Test
Frame (STR1, available separately). Students use masses on
weight hangers to apply various loads to a portal frame.
A backplate holding the portal fits to the Test Frame. The
portal has three members – a horizontal beam and two
vertical members or ?legs? joined at two upper corners. All
members are of the same material and have the same
flexural rigidity (IE value). The backplate holds the bottom
of the portal legs to form rigid fixings. The portal has
sixteen strain gauges – eight along its horizontal member
and four along each vertical member. The gauges connect
to the Structures Digital Strain Display (supplied) to display
their measured strain.
As students apply loads, they use the measured strain to
find the bending moment at the gauge positions and plot
them on a diagram. They can then check the diagram
against one created from theory.
The hardware includes a digital indicator to measure
horizontal deflection (sway) in the portal. It also includes a
pulley bracket so students can apply horizontal loads and
compare sway direction with that predicted from theory.
The hardware also includes two removable moment arms.
Students may fit one or both moment arms to the frame
to simulate internal or external floor supports on the sides
of a portal structure. Students can find the bending
moments caused by these supports and compare with
theory.
The lecturer guide provides details of the equipment
including sample experiment results. The student guide
describes how to use the equipment and gives experiment
procedures.
For extra ?virtual? experiments, TecQuipment can supply
the optional TecQuipment Structures Software (STRS), for
use on a suitable computer. The virtual experiments
simulate the tests you can perform with the hardware.
They also extend the choice of tests beyond that available
using only the hardware, for example: higher loads,
uniform loads or different test specimens. This extends the
student?s learning experience.
For automatic data acquisition of your experiment results,
TecQuipment can supply the optional Automatic Data
Acquisition Unit (STR2000). Supplied as standard with the
STR2000 is TecQuipment?s Structures Software that
displays and logs your experiment results and gives the
extra virtual experiments.