[easygroove]

All, some general metro design questions for a CBD environment:

Is there a rule of thumb for sizing station entrances? Widths, vertical transportation requirements etc (Patronage forecasting will confirm sizing later)

Is there an optimum arrnagement for entrance points? eg. stairs flanked by escalators, no escaltors, lifts + stairs

Should sub surface connections (free from traffic and delays) from accesses, to station be preferred when compared to introducing improvements to surface conditions for pedestrians accessing metro.

Any refrence docs or advice welcome.

[bmfarley]

All, some general metro design questions for a CBD environment:

Is there a rule of thumb for sizing station entrances? Widths, vertical transportation requirements etc (Patronage forecasting will confirm sizing later)

Is there an optimum arrnagement for entrance points? eg. stairs flanked by escalators, no escaltors, lifts + stairs

Should sub surface connections (free from traffic and delays) from accesses, to station be preferred when compared to introducing improvements to surface conditions for pedestrians accessing metro.

Any refrence docs or advice welcome.

I do not have the standard at my finger tips that you're asking about. I suspect it's only a rule of thumb or a local agency would review what is typically applied elsewhere... and based on some future date and anticipated users. Also taken into consideration could be the dynamics of how users are likely to use the system (Directional flow, peak tiems, etc). It seems an architect familair with the design of stations for high use areas should be able to anser this question better than myself; however, I'd think of something likethe below.

Up to 2,000 daily:
Stairs 10' wide
1 Elevator (to meet ADA requirements)

2,000-5,000 users:
Stairs 15' wide
1 elevator
2 escalators

5,000 to 8,000 riders:
Stairs 20' wide (perhaps 2 sets)
2 elevators
2 escalators

I would think additional factors come to play... that cannot easily be expressed above... such as directional flow at peak times, local phyiscal conditions, overall vertical distances involved, the pulse of users released from arriving trains, emergency egress requirements, etc. In fact, local fire regulations could play a large role in answering your question.

[bmfarley]

Coincidentally, I just came across the answer last week... and for the mnost part, I was correct when citing emergency egress.

Essentially, stations need to accomodate the emergency evacuation of passengers from two fully loaded trains in a set amount of time. I am unsure if those trains would be 'crush' loaded or standard/commute loaded... and if platform passengers are taken into consideration... or if the time factor involves something like frequency of trains... like get all those people out before the next train would arrive.

The next part of the answer woudl then be... what is the processing power of the portals and stairwells and escalators and so forth.