Any structural steel oracles?

[Tim Frank]

I've got a boathouse built over the water....wood floor., approx. 20' x 14'.....22' length runs to the lake.
Six point suspension. Two inner corners on land. Mid point of each side and outer corners supported by concrete piers..

The joist plates that run down each side are full 2" x 10" rough-sawn hemlock, doubled. They are rotten and need replacing.

I'd like to use steel I-beam as replacement. Anyone comfortable recommending a replacement?
It looks to me like a W6 x 15 lb/ft would be fine. Longest clear span between columns is 8'.

Opinions?

 

[Bigprairie1]

Re: Any structural steel oracles?

Any driving reasons for the wide flange Tim? do you have any quick pics of the dock that show the existing joists?
Are there any impacts to the upper surface/deck or lower components that would occur because of the shallower section of the new beam (ie: W6x11.5#)? ....ie: 6" vs. 9.5"....3-1/2" missing in height.
BP

 

[dingbat]

Re: Any structural steel oracles?

An S8 x 18.4 with a 2" x 4" or 2" x 6" header (spacer) would work, provided you could secure the beams to the concrete pilings.

 

[Tim Frank]

Re: Any structural steel oracles?

Any driving reasons for the wide flange Tim? do you have any quick pics of the dock that show the existing joists?
Are there any impacts to the upper surface/deck or lower components that would occur because of the shallower section of the new beam (ie: W6x11.5#)? ....ie: 6" vs. 9.5"....3-1/2" missing in height.
BP

Just for a bit of added stability. I could go with an S6 x 12.5.....or what would be great would be a S5 x 10....better weight to work with....
The beam actual section will be no impact....I am planning for it in any event.

Pic attached.

 

[Bondo]

Re: Any structural steel oracles?

Ayuh,.... With that tiny load, find yerself an old house trailer frame,...

The main i-beam rails measure 'bout 2x10, 'n are fairly light weight,....

I've been usin' 'em to jack my 2 story rental house at 13' centers, blockin' 'em solid, as it'll twist abit under my heavy loads,...

That little place, on 8' centers shouldn't be bad at all,...

I found mine at the local scrap yard last year,...
I hauled in 1000 lbs of scrap, 'n left with 'bout the same tonnage,.... Cheap....

If ya don't think they're heavy enough, Double 'em up,...

 

[dingbat]

Re: Any structural steel oracles?

Just for a bit of added stability. I could go with an S6 x 12.5.....or what would be great would be a S5 x 10....better weight to work with....
The beam actual section will be no impact....I am planning for it in any event.

The larger flange of the W section is opposite the direction of the load. It would reduce deflection left and right but little affect on it's load being capabilities.

Going from a S6"x 12.5 to a S5"x 10 would decrease your load capability and increase deflection by roughly 20%