Bridge Engineering Visualization
Rather than using energy intensive processes to bend sustainable bamboo into shape post harvest, Alexander’s unique approach involves manipulating the bamboo stalks during the plant’s growth process. Tension is applied to the bamboo stalks as they grow over a reusable skeletal sub structure, that forms the structural basis of the vehicle. The natural energy from the plant does all the rest!
Anybody know what the splice or lap length should be for ties in reinforced round columns?
I would think it would be considered a class C splice in the ACI code. Somebody in our office also thought they should be considered top bars, I disagree with that idea.
If you look up this issue on the Internet it is pretty difficult to find a solution.
Thanks!
Introduction to Sketchup Part 2 with some Google Earth. Best viewed at 720p.
Okay it is a stupid idea but it is Friday! The levers squeeze the arch deck……hey I was bored.
So I was thinking, how could I use high strength concrete in a ABC county bridge? Concrete in the range of 30,000 psi compressive strength. (206,842,718 N/sq.M)
Well I thought, an arch system, is the way to go, because arches are in compression, and concrete loves compression. So, on break, I came up with a really shallow precast thin arch panel bridge, which I think could be built quickly in the field.
Two problems (well lots of problems), one, the panels are the deck so you would have a “hump” on a road which could cause a fun jump at high speeds and two, I think you would need to post-tension parts of the bridge to keep the panels in compression. (Integral abutments can flex losing some of the compression forces)
I placed some tensioning strands on the outside of the bridge, so you could get at them and see when they need re-tightening. The panels would also have to have cross strands and shear keys to keep the deck working as a whole system. The railing could be the typical county rail that gets bolted on or you could place a slip formed rail, tied into the panels.
Okay here it is, and remember it might not work…….
Some more images…… Read More >>
Highway 405 in California is closed for the weekend, so they could remove the Mulholland bridge, a variable depth concrete bridge.
Meoowwww, the winner of the designbymany bridge competition is not actually a bridge….it is a series of dancing girls in front of a bridge. I’m not even going to give a link, you can find it.
Well designed, well presented but not a bridge concept. (yes I am the king of sour grapes)
Things are a little quiet of the bridge front. I have finished my summer teaching ( I know you care) and I am waiting to hear about the fall. (teaching is outside my full time job)
I have also contacted a number of bridge engineers, hoping to start a series of short interviews for this blog. I thought it would be interesting to read about practicing engineers and their projects. (well maybe I will be the only one reading it…) But as you can imagine it is difficult to get responses to “cold” emails asking for answers to questions…..for a goofy bridge blog.
The idea was to ask five questions which would be short enough for a blog post, be interesting and manageable for a engineer to fit into their schedule. We will see how it goes.
What else? I have come to hate my usb Blue Snowball microphone. I can’t seem to get good sound out of it unless I am in a padded room and I hold the mic two inches from my face. (I believe that is two kilotonnes away for you metric types…) I wanted to make some “GOOD” videos for a change but, hey its the mic’s fault….(no really.)
One other idea I have been working on is a use for the ultra high strength concrete mixes out there, in “real” bridges, at an affordable price. We seem to use the stuff in traditional shapes (beams) and then pay extra for something we probably don’t need. An arch bridge is the way to go because it is typically completely in compression. I will work on it. (hopefully ABC)
hat-tip to David for some good photos.
Hat-tip David.
An interesting project in France with a bridge!
Since 1995, when the French State and the Syndicat Mixte Baie du Mont-Saint Michel became involved, and subsequently the launch of the initial works in 2005, restoring the Mont to its marine setting has turned out to be one of Europe’s most original and remarkable site restoration operations. The European Union, which is contributing funding, has highlighted its dimension as a genuine sustainable development project to serve the area.
The main idea is to restore a marine setting to Mont St- Michel with tidal water all around on a regular basis, by using the combined power of the water from the incoming tide and from the River Couesnon. Reclaiming the sands in this way also means doing away with the 15 hectares of car and coach parks, as well as the causeway linking the rocky island to the mainland, as they have blocked the tidal currents for over 130 years.
The idea is also to have a completely new approach to the monument for the 3 million sightseers who come to see it, and often faithfully come again. From the mainland up to the Mont, a new approach road is to be constructed: you arrive at a parking area with reception and information services, 2.5 km (1.5 mi) from the Mont, and take the footpaths or public transport shuttle. You will then be able to taste the old spirit of crossing over to Mont St-Michel, taking the time needed to take in the bay scenery, stopping off at the dam then the pedestrian footbridge offering an unbroken view of Tombelaine rock, Mont St-Michel and the bay.
These new conditions of access to the rock will play a crucial role in controlling the influx of tourists. They will help to preserve, now and for future generations, the abbey approaches, a major cultural and spiritual destination, and the natural landscape of the bay listed as a Unesco world heritage site.
