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View Full Version : Invitation to tender: New "Millau - Meouw" bridge (Sir Norman Foster welcome)...


airship
26th May 2014, 16:51
Please submit your official tenders and/or advice concerning replacement of existing bridge with more modern and light-weight version:

Existing bridge specifications:

Dimensions: Overall length (single span, unsuspended) = 4,240mm; width = 60mm; single-lane for pudicats approx. weight 4-7kg.

Construction: Hard wood, using 60x40mm timbers with single over-lapping junction of approx. 40cm at mid-length. All secured by stainless steel 316 wood screws. Additional "non-slip" surfacing to "traffic" surface using woodsaw in "X" pattern every 25mm approx. "Stabilisers" approx. 25cm width using 60x40mm timber fitted at each extremity.

Comments: This rudimentary bridge has provided extremely satisfactory service for regular use by pudicats between 1991 and approx. 2010. However, more recent pudicats do not like using it because of A) Limited width of 60mm only. B) Important flexing and creaking noises.

---XXX---

NEW bridge specifications:

Dimensions: Overall length (single span, unsuspended) = 4,240mm; width = 100-120mm minimum; single-lane for pudicats approx. weight 4-7kg.

Construction: Hard wood, aluminium, composites etc. all acceptable (I can supply the "non-skid" surface covering).

Site limitations etc.: 1) Max. length for transport of materials onto site 2,500mm. 2) Assembly on site: no welding facilities, assembly should consist of either adhesives and/or bolts, nuts and washers.

Max. cost (excluding assembly): EUR 50-75.

PS. What is it with pudicats ca. 2014 that they can't / won't use a 60mm wide creaking bridge to come and eat or just "have a wander"...?!

PPS. This is especially for "Mummy cat".

airship
26th May 2014, 19:33
Oh FFS, it's a simple bridge, to connect my 1st floor balcony across to the high wall approx. 420cm away, across which pudicats might traverse safely...?!

Someone...?! :sad:

west lakes
26th May 2014, 19:36
To assist the tendering process, a photo of the existing structure would be an aid to some I think

Windy Militant
26th May 2014, 19:53
If it doesn't involve welding or at least Wrought iron and hot rivets, It's a plank not a bridge!:p

At least according to the I K boys book of engineering anyway!;)

airship
26th May 2014, 19:58
Construction: Hard wood, using 60x40mm timbers with single over-lapping junction of approx. 40cm at mid-length.

west lakes, try to imagine that. Admittedly, I don't have any photo available because that would oblige me to have an account with one of the usual "hosts" who store such photos without any recompense. And why I cannot.

I'm just wondering if say, 2 sections of 150mm width x 20mm thick hard-wood, each approx. 2.5m long, joined by a simple aluminium "T" profile at the mid-section (for 50cm or even longer) would suffice...?!

Bleedin 'eck. It's all I came here for, before I was drawn by the other threads...?! ;)

er340790
26th May 2014, 20:05
Cat-apult??? :} :} :}

Thank-you, thank-you, you're very kind....

500N
26th May 2014, 20:08
Airship

":Admittedly, I don't have any photo available because that would oblige me to have an account with one of the usual "hosts" who store such photos without any recompense. And why I cannot."


Try using www tinypic com (add a . in the spaces !)


You don't need to sign up to it to use it and it is very quick and easy.

500N
26th May 2014, 20:18
Airship

First idea

Make a T Bar out of wood.
Get 2 x 2,500mm lengths of wood and use these vertically.
Get 2 x 2,500mm lengths of wood and use these nailed to the two above.
I think it should span 4 metres.


2nd idea
Get two 2,500mm square metal pipe and bolt them together to span the 4.2 metre gap. Then bolt some wood to them for the putty cat to walk on.

west lakes
26th May 2014, 20:30
I'm just wondering if say, 2 sections of 150mm width x 20mm thick hard-wood, each approx. 2.5m long, joined by a simple aluminium "T" profile at the mid-section (for 50cm or even longer) would suffice...?!

The two pieces of 150 x 20 sound fine, then get some 50 x 50 timber, overlap on the joint by a fair amount either side say at least 1m top and an overlapped piece of 150 x 20 on the bottom as you have now.
You could actually run the 50 x 50 the full length as a sort of edge rail it would also serve to remove a lot of the bounce from the structure. If you did this get 2.5 m lengths similar to the 150x50 which would increase the overlap (think brick wall)

John Hill
26th May 2014, 20:40
Buy a length of plastic sewer pipe of diameter greater than fully preggers Mummy cat.

Pipe is probably sold in 5m length.

G-CPTN
26th May 2014, 20:54
A 'composite' - several lengths of whatever material you choose 2.5 metres long, but instead of butt-jointing in the middle of the span, stagger the joints (with at least one 2.5 metre length in the middle of the span with overlapping joints at either end of the 2.5 metre central section).
Join with adhesive or bolts to suit your material.

You could even extend the structure beyond the ends of the 'gap' (over the wall as a cantilever).

Windy Militant
26th May 2014, 22:34
Thinking about it and remembering what one of the guys at Old Sarum said about the Hanger that the Boscome Down collection is in How about a Belfast Truss? Apparently first world war hangers were made using this technique as it meant they didn't have to use long lengths of timber.

I couldn't find a decent picture of the Old Sarum trusses but here's a link to Barton aerodrome with a drawing of the truss.
BARTON AIRPORT (http://homepage.ntlworld.com/bryan.burtonbj/barton%20hangar%202.htm)

Noyade
27th May 2014, 00:57
each approx. 2.5m long, joined by a simple aluminium "T" profile at the mid-section (for 50cm or even longer) would suffice...?!I was thinking of aluminium angle running the length of both sides...?

http://i61.tinypic.com/974c5g.jpg

http://i59.tinypic.com/2i7wmkj.jpg

onetrack
27th May 2014, 01:07
Put your cats on a diet and they won't need their bridge doubled in width. Obesity is a global problem. We already have way too many fat-cats.

meadowrun
27th May 2014, 03:20
http://www.millersantiquesguide.com/uploads/expert_blog_images/86.JPEG

Caboclo
27th May 2014, 07:02
Think outside the box.

http://i1.ytimg.com/vi/bjZqZWbmXK4/hqdefault.jpg

Simplythebeast
27th May 2014, 07:09
I believe the procurement team at the MOD could have this sorted within about six years with an initial cost of 400,000 rising to just under 12,000,000 though you would have to factor in the obvious fact that it would never actually be delivered due to cancellation by the government just prior to delivery.Perhaps better to go to B&Q and get those three planks of wood.

Capetonian
27th May 2014, 07:23
https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcTvXPqmJhZfqBjbGNRKP1C_4V5Ws7sD_wgLjswYH87 xJ9ZR_dA5sg

Think laterally. A different way to solve ploblem.

onetrack
27th May 2014, 08:26
Mmmmmm!! Cat!! .... the other white meat! ... :E

acbus1
27th May 2014, 09:11
I don't eat pussy.





...unless it smells of fish.

603DX
27th May 2014, 09:46
airship, funny you should mention Baron Foster of Thames Bank, his "blade of light" bridge would seem amenable to scaling-down to fit your specified span. He might even be persuaded to attend the grand opening and be photographed with arms spread expansively wide, adjacent to a reduced size version for the exclusive use of pudicats.

And if the first line of moggies crossing it should cause some sideways swaying (technically known as "wobbling"), then it can immediately be blamed on the consulting engineer, as he is well aware. Anyway, the web of thin cables along each side will act as a safety net to save any puss unable to keep their balance, I think.

It might look a bit like this, although all of the users (Manx cats apart) will of course have prominent tails ...


http://upload.wikimedia.org/wikipedia/commons/thumb/0/0b/London_Millennium_Bridge_from_Saint_Paul%27s.jpg/400px-London_Millennium_Bridge_from_Saint_Paul%27s.jpg (http://upload.wikimedia.org/wikipedia/commons/0/0b/London_Millennium_Bridge_from_Saint_Paul%27s.jpg)

Dushan
27th May 2014, 11:12
Conveyor belt?

MagnusP
27th May 2014, 11:41
A simple catwalk should suffice.

airship
27th May 2014, 16:05
Thank you everyone, but especially to Noyade for his drawing:

http://i61.tinypic.com/974c5g.jpg

It's what I had in mind more or less and I'll go ahead with your design. If it's not stiff enough, I'll try adding 1m of aluminium "T" profile under the inter-section.

Thanks again Noyade. I'll take a pic of it afterwards. :ok:

PS. "Mummy cat" is a "he" (it's a long story).
PPS. 500N, I'll look into tinypic.com - especially as Noyade uses it...

500N
27th May 2014, 16:15
airship

Glad that all worked out. Look forward to the next installment !

Re tinypic, have helped a few on here to use it who, like me found
the other options a PITA.

G-CPTN
27th May 2014, 16:44
I still reckon it would make sense to have the joins 'not in the middle of the span' - ie divide one timber into two and have a 2.5 metre long piece between the two end pieces (bending moments and shear forces and all that).

Ancient Observer
27th May 2014, 17:00
You need a Butane Gas Torch.

One lick of flame at cat's rear end will cause the required jump.

airship
27th May 2014, 17:13
G-CPTN wrote: I still reckon it would make sense to have the joins 'not in the middle of the span' - ie divide one timber into two and have a 2.5 metre long piece between the two end pieces (bending moments and shear forces and all that).

Absolutely. I'll be using 2 equal lengths of 120-150mm X 20mm hard-wood timber, together with an 'L' or even 'U' aluminium profile as reinforcement. The alum. profile available easily in 2m lengths here would comprise 3 separate sections: the main 2m long section would lay across at the mid-section of the 2 timber planks.

The pudicats will soon be running up and down freely all day and night...?! :(

G-CPTN
27th May 2014, 17:20
I was referring to the timber joins.
(ie keep one timber in one piece and divide the other in half and place at each end of the long piece)
Having the joins at 'quarter' points with a long central piece would be less stressful on the structure and more durable under load.

G&T ice n slice
27th May 2014, 20:26
....arrive in the entrance hall here, and are carried along the corridor on a conveyor belt in extreme comfort and past murals depicting Mediterranean scenes, towards the rotating knives. The last twenty feet of the corridor are heavily soundproofed. The blood pours down these chutes and the mangled flesh slurps into these...

Monty Python's Flying Circus: Just the Words - Episode 17 (http://www.ibras.dk/montypython/episode17.htm)

Dushan
27th May 2014, 21:25
Just because he said "maximum delivery length is 2.5m" does not mean it has to be so. This is an aviation site FFS. Sikorsky Sky Crane can deliver the entire length from above.

Phalconphixer
28th May 2014, 00:24
http://img.photobucket.com/albums/v13/foxbat/MorningSam_zps67b63755.jpg

GROUNDHOG
28th May 2014, 17:45
Surely a simple catapault would do the trick?

david1300
29th May 2014, 01:51
Get a dog - they are just so easily pleased :p

A A Gruntpuddock
29th May 2014, 03:12
I like the the catapult idea, gives you a lot more flexibility as to the distance and bearing.

https://www.youtube.com/watch?v=dv5RICL4gIs

Or you could leave the landing point up to the kitty.

https://www.youtube.com/watch?v=IANwb_qT1gg

500N
29th May 2014, 03:24
That second video is very funny.

Love the footage from the GoPro looking back at the squirrel
as the aircraft flies along :ok:

david1300
29th May 2014, 06:41
Actually, this idea can be very easily adapted for your needs:
rIQ9A28XapQ