I was looking around the Internet and saw an article on the lifting capacity of helium balloons. Apparently it is about 0.062 lbs/cu. ft. So if you have a balloon 100 feet in diameter it can carry about 33,000 lbs..
You could carry a semi-trailer with two balloons.
So I know there is a small pedestrian bridge that has balloons holding it up but how about using balloons to increase the load capacity of existing bridges? Sure they move around but they would be easy to install! Ten balloons, 5 semi-trailers….
C’mon let me try it.
I haven’t posted much lately because I have gone a little bit nuts about fitness and screen printing. The fitness is something we all need and I decided I should try to regain some of the skills I have lost. (Hey I was athlete of the year in college a long time ago…in a galaxy far away.)
Back to screen printing, I started screen printing back in the late 80s in San Diego. At that time, it was big business but I never really got it rolling. So recently, for some reason I bought a heat press, which lead to a better inkjet printer, which lead to screen printing, heat transfer paper and plastisol inks.
So far, just basic stuff but I’m excited I actually got something to work. Now, how does this pertain to bridge design? Both require some visual consideration.
I have something in me that gravitates toward producing Art, maybe lousy Art, but Art. And Art leads to thinking about the look of bridges. You know I’m an advocate for better looking bridges but the more interesting question is how many engineers have creative hobbies?
Do you paint, sketch, print, wrote poetry or do anything the complete opposite of hard core engineering? I would be interested to hear from engineers who do something with the other side of their brain.
David sent me some great links about a former boss, Sir Allan Harris. He seems like an engineer we should all know.
Professor Sir Alan Harris, who died on 26th December 2000, aged 84, was one of the most influential figures in the development of prestressed concrete, and arguably the key player in spreading the ideas outside the French-speaking world. After the Second World War he worked with Freyssinet, first in France, then in the United States, and finally in London. He later went into private practice and became Professor of Concrete Structures at Imperial College.
Most of the time the amount you can spend on a bridge is decided by finding the smallest first cost for a design that’s meets the needs of the project. Why do we do this?
When you buy a car do you buy the cheapest car possible or one that fits your lifestyle? Do you buy the cheapest food, cheapest clothes, house, etc? Nope you are looking for a good mix of value and enjoyment. Something we should do with our bridges.
The reason we build the cheapest bridges is because most of the time we are using public monies. Maybe we need to convince communities of the value and enjoyment a well designed bridge will bring to their lives?