The History of Bridges
In the beginning of bridges, they had short spans usually crossing creeks or rivers. They were also made from naturally occurring materials such as; wooden logs and sticks, stone, dirt, etc. Revolution in the bridge making sense occured in Ancient Rome when they discovered that ground up volcanic rock make very good mortar. The Romans also started the use of arches. The arches held weight very well, and were able to be lighter and stronger than previous bridges. In the 1800's cast iron, which sadly couldn't carry as much weight, but it helped in the invention of steel.
Modern bridges are MUCH stronger than past bridges. The invention of concrete has made them very hardy. This is because concrete erodes MUCH slower than dirt and wood. Modern bridges also use cables to support bridges. Today, bridges can be very long, and can span in between countries, across seas, over valleys.
Bridges of the future are expected to be different than bridges of today in the following categories; materials, construction processes, and modeling. Computers are getting more an more capable of designing bridges. This means that if computer can calculate the angles and engineering generally, then bridges will be faster to make. People also expect to see stronger and more durable concrete and other materials. Inundeveloped countries bridges are going to pop up all over the place.
Types/styles 0f bridges
Suspension Bridges are a type of bridges where there are suspension cables in between towers. Suspension cables are tethered at the ends of the bridge. They also carry most of the weight.
Arch bridges have been around for almost 3000 years. That were popular until steel was invented, steel is more efficient. They are still used though. These were popularized by the Ancient Romans.
A truss bridge is made of connected elements shaped into triangular sections. It transfers the load to a wider area, letting heavier loads use them. They used to be made of wood. Now the are mostly made of metal.
March 29, 2017
Today I finished my concept, design, and working drawings.
March 30, 2017
Today we need to decide which design to use. We decided on mine, the bottom one. We decided on it becuase it left us more wood for cross beams. We also started our top view.
March 31, 2017
Today we need to finishe our top/bottom view and start working on our bridge. Today we finished our top/bottom drawing and started working on our first side.
April 3, 2017
Today we need to keep working on our first side. Today we finished our first truss.
April 4, 2017
Today we need to start working on our second side or truss. Today we finished most of our second truss.
Our second truss! My partner got in the way of the picture.
April 5, 2017
Today we need to finish our second truss. Today we finished our second truss and attached our trusses together at the ends.
The wooooood glue is soooooooo colorful!
April 6 & 7, 2017
I was absent these days and my partner did not take pictures.
April 10, 2017
Here is what our bridge looks like.
Next, we hooked our bridge onto the bucket.
Then we tested our bridge!
April 11, 2017
Today we repaired our bridge by glueing extra pieces of wood with a gallon of glue/mayonnaise.