The purpose of this experiment was to determine whether suspension bridges or cable -stayed bridges would support the most mass.
I became interested in this idea because I want to become an architect someday and I know they build bridges and other structures that have to support lots of mass.
The information gained from this experiment will let engineers know
which bridge type supports the most mass and will let designers decide
which bridge to use based on the flow of traffic the bridge is expected
My hypothesis is that a cable-stayed bridge will support more mass than
a similar built suspension bridge.
I base my hypothesis on my understanding that suspension bridges could
break apart easily if any one of the cables broke. I learned this from
a video clip showing the Tacoma Narrows Bridge falling apart.
The constants in this study were:
The manipulated variable was the design of the bridges I use.
The responding variable was how much mass the model bridges will support.
To measure the responding variable I will add little weights to a container
attached to the bottom of the model bridges. Then I'll weigh the mass in
1.Gather the materials needed such as balsa wood, twine, camera, basket,
The original purpose of this experiment was to see which bridge design supports the most mass. It compared two kinds of bridges: a Suspension bridge and a Cable-Stayed bridge.
The result of the experiment showed that the cable-stayed bridges by far held more mass than the suspension bridges. The first cable-stayed bridge held 10289.6 grams and the second held 6402.8 grams for an average of 8346.2 grams .The suspension bridges held 5509.4 grams and 3629.2 grams for an average of 4569.3 grams.
I observed that one suspension bridge broke immediately after one of
the vertical suspension strings snapped. It should be noted that first
cable-stayed bridge never broke with the full mass on it.
My hypothesis was that a cable-stayed bridge would support more mass than a suspension bridge.
The results indicate that this hypothesis should be accepted because the cable-stayed bridge held more mass.
Because of the results of this experiment, I wonder if using more twine would have had a different affect on the bridges
If I were to conduct this project again I would make sure that I have
extra weights on hand incase I need them. I also would have taken pictures
when I was assembling the bridges.
Top of page