Results

$\backslash$table$[[\backslash$table$[[$Gauge$],[$Number$]],$Load $($N$)],[150,300,450],[1,-150,-313,-467],[2,60,-55,-175],[3,293,181,70],[4,-103,-121,-152],[5,-55,-71,-95],[6,-274,-241,-224],[7,-136,-47,-77],[8,-62,13,67],[9,-188,-116,-74]]$

Report the following

$1-$Tabulate the strain readings corresponding to the different loads.

$2-$Convert the load to a bending moment then fill them in one table.

$3-$Draw the shear and moment diagrams for each applied load.

$4-$From your results, plot a graph of strain against bending moment for all nine gauges $($on the same graph$)$ then answer the following questions:

What is the relationship between the bending moment and the strain at the various positions?

What do you notice about the strain gauge readings on opposite sides of the section? Should they be identical?

If the readings are not identical, give two reasons why.

$5-$Calculate the average strains from the pairs of gauges and enter the results in a third table $($include the nominal vertical positions of the strain gauges$).$

$6-$Plot the strain $($X$-$axis$)$ against the relative vertical position of the strain gauge pairs $($Y$-$axis$)$ on the same graph for each applied load, and then deduce the position of the N$.$A$.($take the top of the beam as the datum$).$

$7-$Calculate the moment of inertia & the centroid location for the section and add the theoretical position of the N$.$A$.$ on a new plot. Deduce the following:

What is the value of strain at the theoretical neutral axis?

Calculate the maximum stress in the section by turning the strains into stress values $($at maximum load$).$ Compare this to the theoretical value.