The experiment involved attaching various loads to the ends of two beams—an aluminum strip beam and a honeycomb beam—to test their resistance to compression and tension. Strain gauges were then used to measure the resulting strain. Measurements were also made of the beams’ sizes and masses. According to the beam type, different equations were used to determine the stress and strain values using the resistance readings from the strain gauges.
The data were analyzed using the strain and stress equations, which are two basic equations. The strain equation uses the resistance values to compute the strain in the beam. The strain values were below 2.5 x 10-3. A positive slope could be seen on the graphs when more mass was added to the beam’s end, and the gage factor was equal to 2.02. The stress in the beam was calculated using the stress equation for aluminium and honeycomb beams. Two separate stress equations, one for each type of material, were utilized. Equation 2 was employed in a basic calculation for the aluminum bar. Hence, the honeycomb beam used a new stress equation to determine the stress brought on by the mass added at the beam’s end. As more mass was added to the end of the beam, the data revealed that both beams displayed a positive slope in strain, indicating a stronger resistance to compression and tension forces. With the additional mass, the stress values for both beams rose as well. The honeycomb beam was more resistant to compression and tension forces than the aluminum beam.
The resistance change is computed using the formula AR/R = (R’-R)/R in the lab steps document’s example involving an Ohmmeter. However, assuming a gage factor of 2.000 and a starting resistance of 120.0 Q, the computed value of AR/R is 0.0004167 for a measured resistance of 120.2 Q. Compared to the exact strain value, this is a percentage difference of about -58%. In the case of the Wheatstone Bridge, the strain is calculated using the formula AR2/R2 = (R2′-R2)/R2, where R2′ denotes the new resistance upon straining and R2 represents the strain gage’s starting resistance. The computed value of AR2/R2 is 0.0009998 for a measured voltage of 2.498 mV using a gage factor of 2.000 and a starting resistance of 120.0 Q. When compared to the actual strain value, this is a percentage difference of about -0.02%.