Lally Column: how to build a robust and effective one?

[angiolino]

hi, sorry for the inconvenience, I should make a lally columns to reinforce a long and slender reinforced concrete beam, 4.90 meters long, 50x50 cm section, 2.90 meters high from the floor, some construction and installation advice, thanks, which material do I use, tubular or boxed what section and thickness? how would you do it? I state that it must not support the load but only the load of the attic which is unloaded thanks.

[Frosty]

Hi angiolino, good to see you post again. Can you put the column in the center of the beam? Cylinder or box depends on a couple things. Are you going to build a wall? If so I'd use square to make the wall easier to build and clad. If open I'd pick the less expensive. 

I don't have ideas to fill it with grout I like, maybe someone reading this will have experience. 

I think that's about what I have for now.

Frosty The Lucky.

[angiolino]

thank you, I hope you are all well and that everything is going well, going back to my question, it is an old house I needed a metal prop to support the beam like a sleeper and unload the weight of the attic and the structure on the ground to distribute the weight in a second moment I will call a company specialized in restoration and rehabilitation, at the moment I want to create temporary temporary props which I will dismantle during the restoration phase, but I have to understand how to make it and what material to use, the columns will remain empty but the upright will have to support the weight in the middle ? how should I do what material do I use, what tricks to use, thanks for everything and sorry for the inconvenience. good life to everyone.

[Frosty]

Is it a single story? The floor is on the ground yes? All you need then is a temporary post, not a Lally post. A simple lumber post with a bracket that holds it in position under the beam you're reinforcing will do it. If there is a basement or the floor is very high off the ground you may need a second support beneath it.

You'll want a sill board under the new post. I'd think simply cutting the timber maybe 10mm longer than will fit in the space between sill board and attic beam's proper height, jack up the attic beam so it clears and slide the new post in place. Screw a couple strong boards on each side of the top end of the beam so they extend up on each side of the beam bracketing it and ease the attic beam down on it. Once it's bearing the weight you can screw the bracketing boards to the attic beam so the post can't shift.

Make sense? Hopefully a real frame carpenter on the forum speaks up and corrects any mistakes I've made. 

Frosty The Lucky.

[angiolino]

there are no support foundations but underneath there would be another ground floor, but I checked the beam is sound, I just have to put a sleeping prop to make the beam rest and unload at the point where it is fractured, but above there are no loads, only the load of the structure of the attic, thanks for your intervention greetings.

 

2.90 meters high from the floor

[Frosty]

There is a room or open space under the floor? If so spread the load being supported by the column across several floor joists under it. If possible put the post directly over a floor joist on a sill board that extends to a joist on each side. The sill board needs to be reasonably strong here I'd use a 2" x 8" minimum, that's what  50mm x 200mm? 

I'm not having any luck getting things to translate to English for me and I'm having trouble visualizing what you have there. I assume the 28cm x 34cm rectangle is the beam you need to support? 

Trave lesionata?  Solaio? 

Frosty The Lucky.

[angiolino]

below there would be a room but I have checked there are no cracks or visible lesions, on the ground under the iron props to distribute the load and balance the forces I have placed a wooden beam above the wooden planks I would like to place a sturdy lally columnb under the crack a 1.30 meters with a U-shaped saddle at least 1 meter long to be placed across the crack to release tension and stress, 34 centimeters is the width of the damaged beam, 28 centimeters thick, too thin in my opinion,
Damaged beam? Attic? they are the beam that I have to fix and secure the attic would be the concrete structure that supports the damaged beam, do you think that the metal props alone are sufficient to make the structure stable or do I have to put stronger lally coulombs in the corners of the beam I had thought of putting some iron angles on it and welding them like a ladder to make the structure more solid, do you think they are necessary or superfluous?
the

http://www.ordinearchitettiagrigento.it/wp-content/uploads/rinforzo-strutturale_large.jpg

 

 

https://www.studioschvarcz.it/wp-content/uploads/2017/05/Interventi-di-ripristino.pdf

[Frosty]

Is the beam you wish to support concrete? If so I'd jack it up a few cm higher than it should be and bolt long reinforcing plates the same width as the beam is high to it. Once you had the reinforcements held in place you can drill through both plates and beam so you can through bolt it all together. This is the same reinforcement method used for many types of cracked and sagging masonry structures. as shown in this publication. https://www.studioschvarcz.it/wp-content/uploads/2017/05/Interventi-di-ripristino.pdf

Building a support structure like in the photo above is a permanent solution suited for heavy buildings, not an attic and roof. You could park cars and light trucks on it. Even pages 67 & 68 show a column that is incredibly strong and so long as it's directly under the crack and rebar is used in the concrete it's many times as strong as you need. Provided I understand the situation.

Unless I'm mistaken you have a one story building with a crack in an attic beam that is sagging.

You can put a column directly between the sagging beam and the ground. Yes? One length of 25cm OD pipe with 12mm thick walls, a spreader plate on top, perhaps an angle iron bracket so it wraps the corners of the beam and a flat spreader plate for the foot. 

If you are having a professional company remodel the building then you really should let them do this and let their insurance cover any future problems.   

Frosty The Lucky.

[angiolino]

it is an infill operation given that the beam is in reinforced concrete and has a slender section I put a temporary support on it a provisional temporary prop, to unload the weight of the floor to the ground, when the construction company intervenes it will adopt the right interventions, but momentarily I would like to shore up the beam for safety, thanks, sorry if I have intruded on you.

[gewoon ik]

It is for a temporary solution? Use these. On the bottom a piece of wood underneed. 2 nails so when you ajust for the hights, you can just stand on the wood and it will not twist away.

these are plenty strong. I used 3 to hold up my house when installing a beam.

 

[Frosty]

We call them "Jack Posts." Common lengths run from a little over 3' / 1 meter to maybe 9' / 3 meters and have different lift capacities, starting at several tons and going up. 

Relax Angiolino this isn't as difficult a problem as you imagine. If you installed a lally column it would probably cost you more when the construction company had to remove it to do the job properly than the job itself. A properly made lally column is a major job to break out involving jack hammers, sledges and pry bars. 

You aren't intruding my friend you always bring interesting questions. Even though the solution to this one is pretty simple I had to do a lot of reading to try  to explain the simple / easy.

Frosty The Lucky.

[angiolino]

 

 

 

 

you advise me to have some metal plates made by an engineering workshop and place them between the beam and the pole, I would like to put a U-shaped bracket under the fracture of the concrete beam, like a channel, a gutter straddling the 2 pieces of beam and right under a pole, or do you think the props you call ??jack posts are sufficient? thanks susate the trouble.

 

[Frosty]

I did a quick search before and images showed many jack posts with brackets, you might be able to buy one that fits. Extending it to each side of the crack is a good idea but no need to get carried away, 30cm on each side is probably more than enough. 

You are installing a temporary support until the company doing the remodel starts the job. Yes? 

You need a temporary support, a lally column is a permanent support. Perhaps specify in the contract the builders doing the remodel install a lally column. That way they can make it fit in with the requirements of finishing the room. Finishing meaning the sheet rock or lath and plaster, paint, wall paper or however you chose to finish the room for use. 

I'm going to use an analogy, I hope it translates. If this next paragraph doesn't make sense ignore it. All you need is a temporary support. Making a permanent one would be like flying to a different country for a one week vacation and buying a new car (permanent solution) rather than renting one. (Temporary solution) Both would do the job but one creates more problems than it solves. 

Frosty The Lucky.

[angiolino]

thanks for the comparison, so you believe that temporary carpenter construction props are sufficient, which at the time of the restoration will be disassembled to restore the beam thanks sorry for the inconvenience, thanks.

 

[Frosty]

Yes, a temporary support should do what you need nicely. 

You're never an inconvenience angiolino, I enjoy hearing about your projects and getting to be a small part of them is a good thing.

Frosty The Lucky.

[gewoon ik]

yes. those thigs are designed for what you want to do.

Good luck with the renovation of the building

[angiolino]

thanks I hope to hear from you soon sorry for the inconvenience thanks for your availability greetings and good life to all.

[Frosty]

You're welcome, it's my pleasure. All my best to you and yours.

Frosty The Lucky.