The Forestry Forum is sponsored in part by:

iDRY Vacuum Kilns


Forestry Forum
Sponsored by:


TimberKing Sawmills



Toll Free 1-800-582-0470

LogRite Tools



Norwood Industries Inc.




Your source for Portable Sawmills, Edgers, Resaws, Sharpeners, Setters, Bandsaw Blades and Sawmill Parts

EZ Boardwalk Sawmills. More Saw For Less Money!

STIHLDealers.com sponsored by Northeast STIHL


Woodland Sawmills

Peterson Swingmills

 KASCO SharpTech WoodMaxx Blades

Turbosawmill

Sawmill Exchange

Michigan Firewood, your BRUTE FORCE Authorized Dealer

FARMA


Council Tool

Baker Products

ECHO-Bearcat

iDRY Wood Lumber Vacuum Drying for everyon

Baltic Abrasives Technologies Nyle Kiln Dry Systems




Author Topic: Da vinci self-supporting bridge  (Read 1604 times)

0 Members and 1 Guest are viewing this topic.


Offline Don P

  • Senior Member x2
  • *****
  • Posts: 5290
  • Location: Southwestern VA
  • Gender: Male
    • Share Post
    • Calculator Index
Re: Da vinci self-supporting bridge
« Reply #1 on: October 05, 2018, 08:44:26 PM »
We've built several with the school kids using poles and lashing rather than notching, great fun. You can make the crosspieces longer for a Quonset type hut, using the same technique and a little more lashing a picnic table. I don't think we went more than about 20' with one. I went to a suspension bridge with them after that. I think we spanned about 35' with the group but I built the test one here at 75' span. They had a ball but the big hit was the crawdads in the creek :D

In the west we credit Leonardo with its invention. He was commissioned by the Medici's to design a bridge for military operations that could be quickly and easily built with materials readily available, and he succeeded. However, unknown in the west, the Chinese had perfected the rainbow bridge about 500 years prior.
A laborer works with his hands
A craftsman uses his brain and his hands
An artist uses his brain, his hands, and his heart

Offline wesdor

  • Senior Member
  • ****
  • Posts: 777
  • Age: 72
  • Location: western Illinois
  • Gender: Male
    • Share Post
Re: Da vinci self-supporting bridge
« Reply #2 on: October 06, 2018, 10:24:06 AM »
I don’t have good internet at the moment so have not watched your video. 

Currently in Italy and visited the DaVinci museum in Firenze on Wednesday. They had working models of the bridge as well as pre-made pieces for you to build your own model.  When I get back home I’ll try to post some of the photos. A most interesting concept (even though the Chinese may have invented it first).  

Offline Don P

  • Senior Member x2
  • *****
  • Posts: 5290
  • Location: Southwestern VA
  • Gender: Male
    • Share Post
    • Calculator Index
Re: Da vinci self-supporting bridge
« Reply #3 on: October 06, 2018, 04:31:47 PM »
wesdor, if you have plans to visit Florence one of DaVinci's contemporaries, Brunelleschi, built the dome on the cathedral there, the largest uncentered masonry dome of the time. I believe there is a museum of some of his work and inventions. He's the person who gave us perspective in painting, another incredible mind of that period.
A laborer works with his hands
A craftsman uses his brain and his hands
An artist uses his brain, his hands, and his heart

Offline btulloh

  • Senior Member x2
  • *****
  • Posts: 1393
  • Age: 66
  • Location: Midlothian, VA
  • Gender: Male
  • I never met an air conditioner I didn't like
    • Share Post
Re: Da vinci self-supporting bridge
« Reply #4 on: October 06, 2018, 05:57:11 PM »
Just to be clear, "The Construction of My Rainbow Bridge" is not MY rainbow bridge.  MY rainbow bridge is yet to be built.  

Thanks for the replies.  Yes, most of the references I see attribute this to the Chinese.  Perhaps Marco Polo brought back some sketches.  I think he was a couple hundred years ahead of da Vinci's time, but it stands to reason.  A lot of trade took place during that whole time.  Ideas travel.

Anyway, it looks like an interesting thing.  Seems that it can scale up or down as needed, to a point.

I need a couple small foot bridges and I'd like to do something more interesting than a couple logs with planks, but don't want to turn it into some sort of major project.  (It only needs to span about 20 feet.)  

Don, do you think  the rainbow design is quicker to execute than a small suspension bridge?  I'll probably choose one based on materials and time required.  If that doesn't pan out I can just fall back to the logs and planks.  The rainbox thing kinda fascinates me though, but that is what gets me in trouble.

Wesdor, enjoy your time Italy.
HM126

Offline Don P

  • Senior Member x2
  • *****
  • Posts: 5290
  • Location: Southwestern VA
  • Gender: Male
    • Share Post
    • Calculator Index
Re: Da vinci self-supporting bridge
« Reply #5 on: October 06, 2018, 10:54:43 PM »
The DaVinci bridge is quick, you can mock one up in minutes with some small pole stock. It is not a particularly comfortable bridge. If you treat it as the arch under the deck and run a gentler arched deck on posts above it, it becomes a nicer bridge. A suspension bridge with a non rigid deck is not much fun to walk on as your weight moves across a flexible deck it changes the shape of the main suspension cables. With a rigid deck they get better, with sway stays even more comfortable, getting more complex as you go. We "evolved" the bridge with the kids to show those concepts.





I like a trussed bridge, which can form the frame for a covering roof.








A laborer works with his hands
A craftsman uses his brain and his hands
An artist uses his brain, his hands, and his heart

Offline btulloh

  • Senior Member x2
  • *****
  • Posts: 1393
  • Age: 66
  • Location: Midlothian, VA
  • Gender: Male
  • I never met an air conditioner I didn't like
    • Share Post
Re: Da vinci self-supporting bridge
« Reply #6 on: October 07, 2018, 05:36:19 PM »
Good info, DonP.  I think the trussed bridge might be the best overall choice.  I have a large collection of cull 2x4's that I may use to mock up both the rainbox bridge and a trussed bridge. I'm really swamped with things to do right now, and I think adding a couple new things would help reduce the backlog.   :D  I really could use a little diversion though.
HM126

Offline wesdor

  • Senior Member
  • ****
  • Posts: 777
  • Age: 72
  • Location: western Illinois
  • Gender: Male
    • Share Post
Re: Da vinci self-supporting bridge
« Reply #7 on: November 11, 2018, 09:10:53 PM »
Finally got the photos from the DaVinci Museum in Firenze uploaded.  You may choose English or Italian for the description.  The other two photos are of the models in the museum.












Share via delicious Share via digg Share via facebook Share via linkedin Share via pinterest Share via reddit Share via stumble Share via tumblr Share via twitter

xx
Supporting the disease!!

Started by Grizzly on Sawmills and Milling

9 Replies
1405 Views
Last post February 04, 2016, 01:10:55 PM
by rjwoelk
xx
Wrap and Strap - supporting the vertical load of sheathing?

Started by John P. on Timber Framing/Log construction

10 Replies
3382 Views
Last post July 20, 2015, 02:06:15 PM
by JimXJ2000
xx
Ice bridge

Started by Quebecnewf on Forestry and Logging

9 Replies
1149 Views
Last post December 29, 2013, 09:58:41 AM
by Quebecnewf
xx
Bridge help

Started by Splinter on Forestry and Logging

1 Replies
961 Views
Last post January 15, 2011, 09:34:14 AM
by Mark K
 


Powered by EzPortal