construction help lally columns

[pietromarruggio]

hi, excuse me if I bother, I should prop up a reinforced concrete beam 4.80 meters long section, 50x 50 cm fractured at 3/4 of the length they advised me to put props on it, yes but how to make them and install them, in metactic tubular of the lally columns they asked me said, how should I make them what material do I use, between the concrete and the prop I should interpose some timber thanks.

Lally Column

Lally Lock Structural Column

https://storage.heightslibrary.org/materials/hrrc/24-General_Interior_Carpentry/LALLY_POSTS.pdf

[MMW]

Not sure of your exact question? You can use steel or wood. How much weight is on it? Typical columns I install are 3in x 3in x 3/16 wall or 1/4 wall. Somtimes we use 3-1/2in tube. For a concrete beam I would make a "U" shaped saddle like in your first picture at the top. Bottom plate bolted to floor.

[pietromarruggio]

exactly I want to make a saddle bracket an open U type gutter section 50 x 50 cm, yes but how long and what thickness, then I should make the vertical box-shaped metal prop, a square 100x100x 3 mm I think it can withstand 4000kg loaded with a tip I think the floor is unloaded, you recommend a column with a round circular section or with a square or rectangular base, which one distributes the weight better, at the ba I would like to make a 40x 40 mm or 50x 50 cm square plate with reinforcement gussets what do you think? ps the beam is currently securely supported. thank you.

[MMW]

No one can give you definite answer because we do not know loads or construction of the beam. You say "reinforced concrete beam 4.80 meters long section" which can be rebar or i-beam etc. I can only make an educated guess based on my experience as I am not an engineer. Almost all columns I have installed use square tubing, smallest being 3" x 3" and largest being 4" x 4". Wall thickness varies also from 3/16" to 3/8". The norm being 3/16" or 1/4". We typically use minimum 8" square bottom plates 3/4" thick that sit directly on a concrete footing and are bolted in. The top plates vary in size but are usually 3/4" or 1/2" thick and span the width of the i-beam less 1/4" on each side to leave room for welding. 3mm wall thickness seems to thin, I would use 5mm or 6mm. As far as the saddle, I would use 1/2" plate with gussets coming out to the end. Beam is about 16 feet long and the length of the channel would be determined by how many columns, load on beam and condition of beam which I can not advise as I have no knowledge of this.

[pietromarruggio]

would you be so kind as to draw me a little drawing, sorry, in the corners I would like to put 2 angled iron sections along the entire length of the beam joined by flat iron crosspieces to form like a staircase and underneath I would like to put the small pillar with the saddle as a support U , I would do it empirically, I can assure you that the attic is unloaded therefore it should support its own weight, as you advise me, therefore the Lalli columns pillar should be made in square box, right? Thanks for your valuable suggestions.






join steel H-beams or C-beams. do you think it is superfluous?

http://prev.enea.it/2019-10-18%20ischia-LaccoAmeno-LeonoriM.pdf

https://www.romatrestrutture.eu/data...20e%20cerchiat ura.pdf

[MMW]

Are any of the photos in the actual beam? Forgive me for all the questions as I am trying to understand the job. Why do you need to support the beam if there is very little load above? Is the beam failing? Was the beam never strong enough from new? Is the space under the beam living area where columns will affect it's use?

[pietromarruggio]

the attic is propped up this is the current situation i think the telescopic carpenter props are sufficient i just wanted to add the v saddle bracket as a support, but i don't know how to size it, just this thanks.

[MMW]

I think you are doing one column under fractured area? Square or round, either will work. A flat plate top and bottom will be ok as long as it is fastened to beam and floor. It would be best to dig through floor for a footing, not sure how thick current floor is? You are putting in a support where there was none but if the beam was repaired fully the load should be minimal. You can make the column wall thickness 5mm instead of 6mm. I assumed the beam has been cosmetically repaired and not structurally sound in the fractured area.

[pietromarruggio]

momentarily there would be 7 props and wooden planks as in the original photo, I want to put a U-shaped saddle bracket at least one meter long and one meter twenty and under the sleeping beam as you suggested, then the plinth-type base would go underneath I err? What do I do, do I leave it leaning or do I balance everything? I wanted to add some perimeter corners in the corners of the beam joined with the plate what are you saying, are they superfluous or are the wooden planks enough?? thanks sorry for the inconvenience.

[MMW]

Your drawing shows the column not centered under the fracture? Can it not be directly under the fracture? Definitely a language barrier here between us. The beam only needs to be supported a short distance on each side of the fracture unless the beam is unstable. Bottom of beam should sit on top of column (concrete to steel) with no wood/timber in between. If you wish to make a U shaped bracket then it can be 5mm, but you still need a top plate on the column for the U shaped bracket to rest. Are you trying to make the whole beam stronger? I am sorry I am having so much trouble understanding.

[pietromarruggio]

basically I put 7 props on them as in the photo of the wooden planks, in the area of the fracture I would like to put like a shirt, a U-shaped bracket to be inserted into the beam in the fractured area for at least one meter between the two parts of the beam and below the column and a 30x30 cm 40x 40 cm base on the ground, I think I was clear, instead of the wooden planks I wanted to put metal corner pieces to protect the edges joined in parallel by flat iron crosspieces like a ladder if you know what I mean. thank you sorry for the misunderstanding thank you.



https://www.romatrestrutture.eu/data...20e%20cerchiat ura.pdf

[Sberry]

I thought I had bout seen it all, guess not.

[pietromarruggio]

going back to the previous work as a temporary infill work, do you think a 5 mm U-shaped saddle bracket in press-folded sheet metal, a 5 mm 30x 30 cm base and a 2.7-metre high metal tube with a 100 mm section, I'm right, maybe between the pipe and the plates we weld sheet metal reinforcements? okay in your opinion, thank you greetings.

http://sipaitalia.it/wp-content/uploads/2018/02/piastre-portapali-regolabili.jpg

[MMW]

1) U shaped saddle - 5mm yes.
2) Metal tube - 100mm square x 5mm wall thickness, yes.
3) Top plate of tube - 5mm thick x 30cm x 30cm with gussets - yes. If I were doing it I would use 12mm or 15mm thick with no gussets. Weld this plate to U shaped saddle.
4) Plate on bottom of tube - 12mm or 15mm x 250mm x 250mm bolted into concrete floor, yes.

[pietromarruggio]

thanks for the valuable advice, I have to find a mechanical workshop that makes the various pieces, thanks again.