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Author Topic: How to simulate escalators (and stairs (at the same time))?  (Read 5038 times)

Robin

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How to simulate escalators (and stairs (at the same time))?
« on: August 29, 2013, 10:39:30 am »

Hi,

I need help.

I have a large project were both escalators and stairs are going to be used for emergency exiting. How to do it?

The easiest way would be two different stairs with two different properties.
Now I´m thinking, perhaps measure flowrate and make the other one wider than the other one.
Since I have 12 escalators, three different types and at least 20 different stairs, it seems tough.

Awesome program by the way!

//Robin
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Charlie Thornton

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Re: How to simulate escalators (and stairs (at the same time))?
« Reply #1 on: August 29, 2013, 01:41:23 pm »

Thanks!

It depends on what sort of argument you want to make when you present your results. You could be conservative and say the escalators might not be operating during evacuation and just model them as normal stairways with no changes. Widening the stairs to give the same effective flow rate as a working escalator sounds like a good approximation, but like you said, it's not trivial to know what that flow rate would be.

In Pathfinder 2013, we added an option to put a speed modifier on stairways to simulate escalators, but in doing so we realized it was difficult to get right. Some people will just stand there, some people will walk up, some people will want to walk up but might be blocked by a pair of people standing. A case we don't deal with well at all is when a queue has formed at the exit from the escalator. Our escalator occupants just stop moving, but that could be a nightmare in real life.
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Robin

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Re: How to simulate escalators (and stairs (at the same time))?
« Reply #2 on: September 02, 2013, 07:07:13 am »

I have been simulating alot since my post.

I´m using the formula in the manual to calculate my desired/possible flowrates.

And of course, I would like to reach the highest possible flowrate for every type of stair all the time, but perhaps
some of the quingproblems you mentioned, reflects a part of reality.

Thanks for the reply.

Best Regard
//Robin
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Charlie Thornton

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Re: How to simulate escalators (and stairs (at the same time))?
« Reply #3 on: September 03, 2013, 07:56:58 am »

Could you send me the reference you've been using for your escalator flow rate calculation? It would be helpful for Pathfinder 2013 validation.
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Sofia

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Re: How to simulate escalators (and stairs (at the same time))?
« Reply #4 on: September 05, 2013, 03:34:34 am »

Hi,

I have the same problem in one of my projects, where both escalators and stairs are used for evacuation. I really liked that one of the new functions in Pathfinder 2013 is that you could specify flow rates through doors and stairs/escalators, but unfortunately it doesn't work for me. I have assigned a specific flow rate for the stairs that will be used as regular stairs which is less than the flow rate being used for the escalators. When I later look at the results the flow rates are significant lower than what I specified for both the stairs and the escalators. How come?

Kind regards,
Sofia
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Charlie Thornton

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Re: How to simulate escalators (and stairs (at the same time))?
« Reply #5 on: September 05, 2013, 09:13:33 am »

The flow rates limits in Pathfinder act as gates that force occupants to wait if another has recently used the door, but they don't have a mechanism to speed people up.

The easiest ways to get occupants to move faster are to make changes to the Speed (maximum velocity) and the Acceleration Time (time it takes to go from 0.0 m/s to maximum velocity). These options are on the Movement and Advanced tabs of the Edit Profiles dialog.

One approach might to to set up the door flow rates you know you want to see, then make the occupants fast enough that the door flow rate limits are the controlling factor in the simulation - rather than movement through the rooms.
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