Week 2 jintao huo

The activity for this week is “frame�, this activity ask us to build a tower by using thin balsa wood and try to build it as high as possible.

Before we start to build our tower, we firstly discuss which shape is better to rise high. Triangle is the most stable shape, so we decide to build a triangle base, this base will resist the deflection from upper tower, so we can build more higher than using other shapes.

Because we think the small base may save more time so we cut our balsa wood into half and use these balsa to build the base and each layer of the tower.

Consider about the stability we build our first level like this

We put all the vertical balsas of first floor into the intersections of triangle. So the two balsas of the base can reinforce the vertical one and hard to fall.

Our vertical parts consist by three rectangles, but we think rectangles are not stable, so we put balsa at the diagonal of one rectangle for each level of the

tower.

When these vertical balsa get weight force from upper levels, these rectangles will get compreession, that is easily to deform, if we put a balsa at the diagonal line when the shape deform, a tension will act on these diagonal balsa and resist the deformtion of these rectangle. That is important.

One thing that I am not sure is the weight of base. I see a very tall tower from other group which can’t stand there very well. Ithink if we put more balsa at the base which increase the weight of the base, is that useful to help the tower standing up?

From this activity I learn that the shape is important for frame, try to put more triangles, it helps frame more stable.