Recent content by davidratcliff6255

Even so, with an FEA model, unless it showed some pretty ectraordinary results, I probably wouldn't be happy until it was confirmed by the sound of things anyway. I'm not convinced yet. Here are some pics of the collapse...

It's already destroyed... What I wanted to do was to load it until whatever happened. I should have kept blocks about 1/2" under the drums so that I could correct, if it was interfering with the aim of the test, which was to see how much of horizontal deflection was being controlled... It...

I've just returned from testing again... CATASTROPHE! I left the weights overnight and today checked deflections again where more sag was noted... up to 50mm in places!... I put it down mainly to the rain we had last night (85 points or 20mm) which may have loosened the footings (which were...

Thanks Javier and PerennialII. Hmmm, Sounds like I won't be able to get out of doing a full test... I did wonder about FE, whether it also would take the extra strength of the arch itself into consideration. I'm sure that with conventional trusses (single web layer) a computer analysis...

Thanks Clausius2... I'll try to post a picture here but I haven't had much luck in the past as I'm basically computer numb... I have managed to (kind of) set up my own msn site though. This is what I call the 'ultimate' using 25mm tube... Please be aware that these designs are very hard to...

Hi, I have a problem! I don't have any formal training in engineering, but have been building and testing all sorts of spanning methods over the past 10 or so years, with some earlier professional help. My main interest at present is in open web trusses/bridges. I have developed a double...

I have recently came across design capacity tables for structural steel (hollow sections). - In the table it shows that 273.1 x 12.7 CHS will not buckle at 1 metre of height (below that, size 219.1 x 12.7 at the same height will buckle at 10 kN less than full capacity if it were fully...

Sorry http://groups.msn.com/DavesBridgesandTowers/_whatsnew.msnw

Am seeking input/help with structual analysis on new bridge design. See: http://groups.msn.com/DavesBridgesandTowers for details Dave

Thanks russ, Is there a scaled down example you can give me? - Say steel, half the thickness of fax paper over a 10 metre radius (probably a lot more), and at what depth? Sorry, I don't understand the maths a bit better...My limit is circumference of a circle, area of a cylinder! - Calculate...

STAii OK but there's not a real lot to tell. I grew up on a farm not far from here. Moved to West Wyalong at age 12. Dropped out of high school at 14. (turbulant teens). Became a bricklayer at 17 and traveled around a bit (mainly the east coast of Aus') Returned to Griffith (100 mls from...

Bridge to 7 km and towers to 3.5 km. (plus other lightweight designs) at: http://groups.msn.com/DavesBridgesandTowers My last thread was just starting to get interesting when the new forum took over! For anyone who missed the final messages, I have recently added more drawings to the site...