Bridge over my pond, can I glue and screw to make a curve?

[Ian H]

Hello,

I'm going to build a bridge over my pond, its doesn't actually go anywhere so I'll rarely be on it, it's more to shade the water and give me something to attach my net too.

Its a 3.5mtr span and I was going to use a pair of 8x2's with noggins between and decking on the top. Then I wondered this, could I cut an arch out of the 8x2 and then glue and screw it back ontop? Would it be quite strong?

Here's a cardboard example of what I though:

I'd really like to go 6" into it in the middle if possible.

What do you think?

Thanks

 

[opps]

I do not know the answer. I am sure that @jobandknock would have though but he is on a "sabbatical".

Off the top of my head, I am wondering if creating a former and laminating several sheets of ply (with appropriate glues) might be stronger. Again, I don't know. Hopefully a grown up will be along soon to offer sage advice.

 

[Ian H]

I've already got the 8x2, i was going to build it flat but just had the curve idea.

 

[opps]

I've already got the 8x2, i was going to build it flat but just had the curve idea.

Other people have done what you suggest,

eg

I have no long idea how long it lasted.

Best of luck

 

[Ian H]

That's excellent, thanks

I'll give it a go, worst case I'll have to buy some new 8x2 and do it flat.

 

[Odds]

You mean to use the off cut wood from the 8x2 on top as a decorative bannister rail, afixing the decking betwixt the two beams to create the pathway: is the decking composite or planked, and how wide will the structure be?

 

[stevie888]

If I were doing that job I'd rip my 8x2 into strips and glue them back together in a curve like a Glulam beam: much stronger

 

[big-all]

my thoughts

i assume its for illustrative purposes as 4 inch over 12 ft is likely some or all off the amount it would sag with a decent load

as in you need perhaps 8 to 12 inch rise to notice so probably wont work in such a simple fashion as all strength relies on small overlaps glued to giveback the strength

maybe glue one on top off the other to give 16" and slope 6" off the ends and a 6" belly giving you an overall 10" and all the glue surface you need