elevator cores & main columns/beams

[lejam]

Hi, has anyone designed elevator for low-rise such as 3-storey where the weight of the elevator is carried by the main beams and columns and not its own box core?

 

[wannabeSE]

The elevator manufactures typically design elevators. Structural engineers design the structure that supports the elevator. Do you have a specific question? Elevators are frequently installed in building without box core.

 

[lejam]

I mean structure that supports the elevator. For low rise buildings where it is not originally design for elevator and only stairs are present and the building already finished. Is it hard to add an elevator? Can the box core be independent to support the elevator cart? Just want some idea before we find a structural engineer so we know our options. I'm just a civil engineer.

 

[hokie66]

Elevators come in two general forms: bottom supported and top supported. Those in 3 storey buildings are often/usually supported on a hydraulic ram which starts in a pit below the lowest floor. Cable supported elevators are supported from structure above the highest floor. All elevators require guides which make the car run vertically and smoothly, without swinging.

 

[lejam]

Can the box core wall system support the elevator itself or does it needs separate columns from the core (or box)? How does human elevator differ to car elevator in terms of structural support? Just need an idea. Thanks a lot.

 

[hokie66]

Not sure what you mean by "box core". If you mean masonry or concrete walls, or structural steel frames, the structure at the top of the shaft can be supported off these vertical elements, and the horizonal elements will in turn support the machinery which supports the elevator. A "human elevator" and a "car elevator" differ only in their size, loading, and of course their architectural finishes.

 

[paddingtongreen]

Usually, box core refers to a system, reinforced concrete or steel framed that acts as an anchor for the rest of the framing so as to leave an open space between the core and the outer walls. Top hung elevators can be supported from any legitimate structural element. In some cases, industrial buildings for example, there are only wire mesh walls around the shaft, with the supports simply part of the building.

Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin

 

[lejam]

Say you have a 3 storey house or storey building and it was built 5 years ago and you wanna add an elevator. What do you guys usually do? Add columns to support it or do you built an isolated box concrete wall to support it or box steel frames? What is usually done in such case?

 

[BAretired]

I think I would contact an elevator supplier in my area and ask them for a little advice.

BA

 

[hokie66]

First you have to work out how to frame the opening, supporting the floors and roof structure in that area. Then you would just add enough capacity to support the elevator machinery and cab, assuming it is a top supported elevator. If it is a hydraulic elevator, you probably only need to make sure there is framing for attachment of the guide rails.

 

[BAretired]

If it is a hydraulic elevator, it would require drilling a thirty foot deep hole to receive the hydraulic ram. That would be difficult unless the proposed elevator is going to be outside the existing building.

BA

 

[hokie66]

BA,
That is one type of hydraulic elevator, but there are others. Telescoping rams are often used, and some of these support the top of the car so that no hole is required below the pit.

 

[BAretired]

Okay hokie, I haven't seen that type so if that is the type contemplated, please disregard my last post.

BA

 

[paddingtongreen]

Which leads to the question of whether you have room for a pit between, and without undermining, the existing foundations.

Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin