14,262 views ·
33 replies
14k views
33 replies
how to attach rebar to wooden beam? unusual solution?
The proposal that "mycke_nu" suggests is a good one, and since you should cast the concrete beam against the wooden beam, you bolt the end to the wooden beam but cast the concrete end inside the pipe. Drill and run four rebar through from one side to the other side of the pipe, then make hooks on a number of rebars and hook these through the continuous rebar and let these rebars go into the concrete beam. Then you cast your beam against the wooden beam, and you have an attachment that is well secured in the concrete.
If I've read correctly among the posts, the wooden beam and the future concrete beam have a common support directly under the joint where both will lie.
Why not install a beam bracket on the end of the wooden beam and let the rebar from the bracket go into the future concrete beam. The only task of the beam bracket would be to hold the wood and concrete beams together. The vertical load from the beams goes directly down into the support, so the bracket doesn't need to handle that load.
Why not install a beam bracket on the end of the wooden beam and let the rebar from the bracket go into the future concrete beam. The only task of the beam bracket would be to hold the wood and concrete beams together. The vertical load from the beams goes directly down into the support, so the bracket doesn't need to handle that load.
I think it will be a mixture of all the suggestions; Flat iron with bolt holes that are welded together with rebar.
4x40 flat iron length 500 with bolt holes 300-400 from the end, welded together with rebar about 100 mm stretch, the rebars will have the full length of the concrete beam. Three flat irons on each side, 6 through bolts M12, at the end of the wooden beam I will cut out a bit on the sides so the rebars enter the concrete. The weld seam will have a slight S-shape.
Edit; it was basically the same as roli wrote above... which I did not read, his suggestion is probably best since the beam shoes for posts are galvanized.
4x40 flat iron length 500 with bolt holes 300-400 from the end, welded together with rebar about 100 mm stretch, the rebars will have the full length of the concrete beam. Three flat irons on each side, 6 through bolts M12, at the end of the wooden beam I will cut out a bit on the sides so the rebars enter the concrete. The weld seam will have a slight S-shape.
Edit; it was basically the same as roli wrote above... which I did not read, his suggestion is probably best since the beam shoes for posts are galvanized.
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Have you had someone calculate the concrete beam?
In a 100 mm wide beam, you can't fit very many reinforcement bars. Since these are the ones that handle the moment at the bottom of the beam, it means that it won't be able to handle very much load.....
Isn't it possible to use a steel beam instead? It will handle much more load than the concrete beam.
In a 100 mm wide beam, you can't fit very many reinforcement bars. Since these are the ones that handle the moment at the bottom of the beam, it means that it won't be able to handle very much load.....
Isn't it possible to use a steel beam instead? It will handle much more load than the concrete beam.
Clearly the best proposal! However, it will take long and many bolts before I would trust the joint.oceanis said:The proposal that "mycke_nu" suggests is a good proposal and since you will cast the concrete beam against the wooden beam, you should bolt the end to the wooden beam but cast the concrete end into the pipe. Drill and run four reinforcement bars from one side to the other side of the pipe, then make hooks on a number of reinforcement bars and hook these through the entire bars and let these reinforcement bars go into the concrete beam. Then cast your beam against the wooden beam and you have a fastening that is well secured in the concrete.
And it's enough to burn a few stumps of reinforcement bars.
So many answers without anyone knowing anything about the load case!
Butt joint - but are we talking moment, shear, tension? What loads are acting? Simply supported, fixed-end?
You must know what loads you're dealing with before you can sort it out...
Butt joint - but are we talking moment, shear, tension? What loads are acting? Simply supported, fixed-end?
You must know what loads you're dealing with before you can sort it out...
Okay, so here's what it looks like: I currently have a mezzanine floor of 5x5 meters with a floor made of the Plannja 200 metal profile.
To explain a bit: Plannja 200 has a profile with a space in the "valley" of 100x200 800mm c-c, and in between on the top of the profile "smooth" sheet metal (google Plannja 200). The space is to be clad with 22x95 planks or chipboard and used as storage space... But, the floor hasn't been installed yet, and the area is still being used as storage.
Since the floor feels shaky and flexes somewhat under the weight today, I was thinking of pouring reinforced concrete in the spaces available in the sheet metal on c-c 800 to increase the load-bearing capacity and stiffen it up.
Next to this space is another area of 5x5 meters, where wooden beams are to be placed at 100x200 c-c 600.
In fact, there will only be three wooden beams that will be cast together with the concrete.
I don't know exactly how much load it will be subjected to, but as much as possible.
To explain a bit: Plannja 200 has a profile with a space in the "valley" of 100x200 800mm c-c, and in between on the top of the profile "smooth" sheet metal (google Plannja 200). The space is to be clad with 22x95 planks or chipboard and used as storage space... But, the floor hasn't been installed yet, and the area is still being used as storage.
Since the floor feels shaky and flexes somewhat under the weight today, I was thinking of pouring reinforced concrete in the spaces available in the sheet metal on c-c 800 to increase the load-bearing capacity and stiffen it up.
Next to this space is another area of 5x5 meters, where wooden beams are to be placed at 100x200 c-c 600.
In fact, there will only be three wooden beams that will be cast together with the concrete.
I don't know exactly how much load it will be subjected to, but as much as possible.
http://www.skantak.cz/obrs_o/trapezy-img-200.png
is this the sheet you mean?
is this the sheet you mean?
Have you called Plannja and asked if it's a good idea to fill the gaps (with seam) with concrete? Even if they probably neither promise nor stand for anything like that, you might at least avoid a "no for faaaan"!hackatall said:
I have not called Plannja on this matter, but many times before on other matters, and as soon as you suggest something outside the box, so to speak, it's -we do not take responsibility for the consequences!! Tips and advice when it comes to unusual constructions, well then you have to turn to building engineers (ambitious ones).
Yes, that's the sheet metal.
Purely logistical: a reinforced concrete beam in the valley of the sheet metal + the sheet metal's load-bearing capacity = better load-bearing capacity.
The sheet metal is, of course, supported during the casting so it does not sag, but when the concrete has cured, the floor should withstand much more than before.
I can calculate the load-bearing capacity of the concrete beam, I am currently taking a construction course in concrete.
Yes, that's the sheet metal.
Purely logistical: a reinforced concrete beam in the valley of the sheet metal + the sheet metal's load-bearing capacity = better load-bearing capacity.
The sheet metal is, of course, supported during the casting so it does not sag, but when the concrete has cured, the floor should withstand much more than before.
I can calculate the load-bearing capacity of the concrete beam, I am currently taking a construction course in concrete.
It works as an intermediate floor, however, it becomes a bit more wobbly than a wooden joist.
But most often it is used as a load-bearing profile between the construction steel in shopping centers, hockey rinks, sports halls, etc.
On top of the sheet, insulation and rubber mat are placed.
So it should at least hold for the snow load!
But most often it is used as a load-bearing profile between the construction steel in shopping centers, hockey rinks, sports halls, etc.
On top of the sheet, insulation and rubber mat are placed.
So it should at least hold for the snow load!