Bridges -- weekly wrap up 2-12-16

This week we went on a field trip!  We visited a local Italian ice store and saw the process of making Italian ice.  

I didn't even know this place existed.  

The machine that packages the flavored ice into plastic cups 

Watching the staff mix ingredients into the machice.  We watched them make lemon Italian ice. 

It only took about ten minutes to turn all the ingredients into an icy slush--we all tried a sample and it was good!

This is a local man and his company and he supplies many of our local grocery stores with his wonderful Italian ice 

Tasting our samples--we of course bought a small cup to go:)

MarioFan has been busy working on his bridge unit.  We finished learning all about Arch Bridges and made a few examples.

We painted the bottom of one bridge set which will eventually hold 3 different type of bridges 

We mixed some plaster 

Using a plastic mold built some stones 

then built our arch bridge--all the blue paint flakes off our model.

Next MarioFan got out his K'nex bridge kit and built an arch bridge

We done a lot of talking about what makes a good arch bridge and look at various famous arch bridges  around the world.
We have also watch several you tube shows on bridge building from a show called mega structures--which is very interesting.

Next we are learning about Suspension Bridges and looking at various components of the bridge and doing lots of experiments.

First we looks at what makes a pillar of a bridge strong and what forces the pillars must withstand in order for the bridge to be successful.  We fill 5 toilet paper rolls, one was empty, one with flour, one with sand/gravel, one with popcorn, and one with marbles.  

We taped up both ends 

We used this form from one of our books to make predictions on which pillar would hold up the best

Next we went outside and tested our pillars by standing on them (acting as the pillars compression)

Some pillars held up very nicely under MarioFans weight while other simply collapse and we discussed why 

The order in which the pillars held up starting with the one that failed to the one with the most success...
air, popcorn, flour, marbles and sand/gravel

Another experiment was to look at how pillars are built either on soil or in the water.  Simply placing a heavy object on the earth surface won't do.  A simple example of using cups that are compressed into sand shows this.

We did the same thing after adding water

A bridge would not hold up under these conditions--so we discussed how bridge engineers came up with a strategy building caissons

We constructed our own caisson using PVC pipes--first we pushed in into the soil until it reached the hard surface

Next we began suctioning out the water once we got as much water out we added  another internal cassion

and began scooping out the mud and water until we reach  the hard surface.

we removed the internal caisson and we put in our pillar 

and removed the outer caisson (Dad got to see this part)

Our completed pillar:)

We are reading about the Brooklyn Bridge and going to watch the documentary next week as well as discuss how the suspension bridge cables are constructed.