Testing the Strength of Structural Members

Testing:

In this unit we learned the difference between tension and compression and the different it effects it can have on a bridge or just on any object in general. Tension has to do more with pulling or the amount something can be pulled before it breaks. Compression deals with pushing or the amount of force an object can take before collapsing or being squished. We used a wood contraption that acted as a lever, and we used sand in a bucket on the end of the lever to produce more and more force on the pieces of file folder paper pieces for the tension test, making them rip apart, and the file folder made columns, that collapsed and squished. We held the wood contraption down with clamps, so it would not just fall off the table when we put the sand bucket on it. We also used clamps to hold the tension strips in place. We used the laser cutter to create the strips of paper for the tension test that were 20 cm by 4mm, 20cm by 6mm, and 20cm by 8mm, 3 of each and 3cm by 3cm squares to go on the end of each for the tension test. For the compression test, we made 3 10mm by 10mm tubes that were 5cm long, 3 10mm by 10mm tubes that were 10 cm long, 3 10mm by 10mm tubes that were 16cm long, 3 6mm by 10mm tubes that were 5cm long, 3 6mm by 10mm tubes that were 10cm long, and 3 6mm by 10mm tubes that were 16cm long. We created the tubes on the laser cutter, as squares with folds, to easily be able to fold them as tubes, we also reinforced them with strips of file folder that were 20cm long and 6mm wide, in order to make them stronger and be able to withstand more force on them. We used a variety of sizes, so we would be able to tell how if taller or shorter, thinner or thicker, would withhold more compression and tension. We did each test one at a time, progressively adding sand to the bucket, slowly, so we would be able to see the exact breaking point of the column or strip of paper. Then would would weigh them and see how they compared to other sizes. There might have been some error when adding sand, like maybe faster one time than the other, and also where the compression testing tubes were located because if the were further back in the wood contraption, it could have helped them withhold more force. Other errors could include how well the glue worked because this might have effect the results of tension test, when the sand makes the strip rip, but other than those few potential errors, these should be close to accurate with a few outliers because there will always be outliers when testing.

Assignment/Project Instructions: