I think two threads are in order today re: trainpoasting First will concern commercial space, second aesthetic rural trains & Acadie
But even in the market, you typically have a collection of stalls or stands, and in an arcade, a row of open-front shops.
-
-
So with this in mind, you can start to think of a geometry of commerce, in which the individual establishment = a point.
-
There are two kinds of transportation that are relevant here: there is getting to and from the commercial space, and navigating within it.
-
The mode of transportation for the latter is always on foot--but for the former, it depends on the sort of commercial space.
-
So, an isolated "point," an establishment without neighbors, may be reached by walking, biking, or driving, but lacks demand for transit.
-
But move from a point to a line--that is, a row of adjacent establishments--and the spatial demands for car access increase drastically.
-
Move up to a plane--establishments in a non-linear cluster--and the parking requirements start getting unmanageable.
-
At this point, with so many businesses, you must either have something like an outlet mall with fields of parking...
-
...or, as is far more often the case, you must have something like a commercial district in a city, with walking-distance houses & transit.
-
Google is helpfully highlighting commercial spaces--this shows point & three varieties of line (small, large, urban)pic.twitter.com/FH62kcZtHb
-
Once your commercial geometry is a plane instead of a line or point, it starts to be impossible to rely solely on cars to bring customers...
-
...it becomes essential to have residences w/in walking distance and some sort of transit as well as parking.pic.twitter.com/ajMblKKnYw
-
The three examples shown are small American city (bus hub), large American city (bus hub & subway stop), & large Japanese city (train & bus)
-
So far we've dealt with points, lines, and planes: single establishment, several in a row, several in an area. You know what's next...
-
...three commercial dimensions. Establishments on multiple stacked planes. Enormous amount customer traffic.pic.twitter.com/VKjrSEEyFb
-
You can manage lines with just cars, planes with just buses...but you *need* the capacity that rail provides to manage spaces.
-
What's so special about rail, though? Why can it provide the most capacity? A brief digression about capacity multipliers...
-
Consider all modes of transportation for what they are--pedestrian movers. You are a pedestrian before you get on, and after you get off.
-
A simple vehicle like a bicycle can move one (sometimes two) person at faster-than-walking speed. It accelerates, but doesn't multiply.
-
Something like a car, on the other hand, has multiple seats--so it can move one person, sure, but also 5 or 6; it has variable capacity.
-
If you have a single lane of road, cars only, then it has a variable *passenger* throughput even at a fixed *vehicular* throughput.
-
Number of seats is the most basic capacity multiplier: a variable which magnifies the frequency on a corridor.
-
Frequency = vehicular throughput = cars (or buses, etc) per hour. 2,000 cars per hour could be 2,000 people or 10,000 people.
-
Vehicular throughput has severe space constraints, so multipliers are important. To move 10,000 people by car, you need...
-
...either one lane of road, at 60 mph, w cars carrying 5 people on average, w/o stopping...or 5 lanes, 1 person avg, same speed, no stopping
-
The higher the capacity multiplier, the lower the frequency you need to achieve the same throughput.
-
Buses have 10 times as many seats as cars, which is a huge boost. Trains have 10 times as many as buses, as they are effectively...
-
...grouped "sets" of buses that move simultaneously. Instead of getting ten buses, one after another, through a stop, move them all at once.
-
It should be clear, btw, that "train" here does not necessarily mean "uses two steel rails." The tech can vary as long as the form is right.
-
The crucial thing is that cars, buses, etc, have one capacity multiplier (seats); trains have two (seats per carriage + # of carriages)
-
So, trains can manage the best throughput per lane, a station with 10 tracks can handle FAR more people in an hour than a highway w 10 lanes
- 12 more replies
New conversation -
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.