RailRunRob Posted March 6, 2018 Share #126 Posted March 6, 2018 1 hour ago, CenSin said: With the adding of side platforms though, less of the tunnel has to be widened, reducing the cost. Widening the island platform would mean moving the tracks and the supports as well. I’d like to think that what Hoyt–Schermerhorn Streets would be a better setup than having everyone mix on a single island platform. The Spanish solution works well when traffic in both direction of travel is simultaneously utilized and passenger flow needs to be separated (getting on versus getting off). But when it is used at the terminals (such as in the Bronx), where passengers primarily board in the morning and get off in the evening, some platforms won’t be used. I'm with you that's an option. From an engineering vantage point let's say Times Square if I needed an additional 7 feet added to the Platform pushing the walls out 4 feet on either side structurally in my mind would be a bit easier. Weight distribution could be done beam section by beam section. In fact, you may be able open the station abit more by redistributing weight via bigger beams and stronger supports just beyond the walls. Think 21st-Queensbridge. You could taper the platform at it ends to line up with the existing tunnel alignment. Digging side platforms would still demand beam alignment to be altered. Digging 8-10 feet out on both sides is way more daunting than a 3-4 foot push what's above me is now more important than ever then add stairways and mezzanine level integration seems more work IMO. None of this would be valid for a station like Grand Central. Just 5th and TS really. My second thought from the engineering perspective is POF (points of failure) Door operation of both sides at a non-terminal might be an added level of complexity for something to go wrong more delays for thru service. Just thinking out loud. But I see your point make sense from a dynamics pov just all the other dimensions along with that makes it hard to tell if it could work or not. Why didn't the IRT use this system or if they did how did it work out? Link to comment Share on other sites More sharing options...
Wallyhorse Posted March 6, 2018 Share #127 Posted March 6, 2018 20 hours ago, T to Dyre Avenue said: In response to the second bolded text, that’s a question that’s always going to be asked, regardless of the whether it’s subway or commuter rail. Because for many people (myself included), the journey doesn’t end when you get to Midtown on the , or PATH, just as it doesn’t for many on NJT/LIRR/Metro North. Forgive me if I’m stating the obvious here, but that’s a question that the study planners best take into account. By funneling even more riders onto the or , the planners need to look at how many of those additional riders will get passed on to the other subway lines and whether or not they in turn can handle it. And yes, it’s easy to see how close the is to the waterline and say that’s less money we’ll have to spend to tunnel under pricey and crowded Manhattan infrastructure. The too - at 14th St, it also has a very short ways to go before it hits the Hudson. But will we really? There may be less tunneling needed for a or extension to Hoboken/Secaucus. But what about the stations in Manhattan? The and line stations have a lot of difficulty handling their existing ridership - at all times. Not just during rush hours. This is something that simply cannot be discounted. Both the ability to cope with additional riders and the potential to expand the existing stations have to be taken into account. And how much it will cost to expand said stations. If what we know about PA or MTA building costs or building in Manhattan in general are any indication, then it’s entirely possible that the costs to expand the existing or line stations will eat the savings of not having to tunnel in Manhattan. The are a couple of big differences with the over the 1. The stations can be lengthened to 600 feet (and in most cases, that is only a 65-foot or so extension because those stations were built to handle eight-car trains of BMT Standards that were 67 feet in length and as a result albeit with a tight fit could actually handle nine-car trains as it is. 2. The would NOT have to make a curve to reach the Hudson as it's already straight on 14th. Then there is the fact the transfers to literally every major trunk line and gives more riders from NJ an easier time getting to and from NJ. That's why I do the over the to NJ. Link to comment Share on other sites More sharing options...
Lance Posted March 6, 2018 Share #128 Posted March 6, 2018 3 hours ago, RailRunRob said: I'm with you that's an option. From an engineering vantage point let's say Times Square if I needed an additional 7 feet added to the Platform pushing the walls out 4 feet on either side structurally in my mind would be a bit easier. Weight distribution could be done beam section by beam section. In fact, you may be able open the station abit more by redistributing weight via bigger beams and stronger supports just beyond the walls. Think 21st-Queensbridge. You could taper the platform at it ends to line up with the existing tunnel alignment. Digging side platforms would still demand beam alignment to be altered. Digging 8-10 feet out on both sides is way more daunting than a 3-4 foot push what's above me is now more important than ever then add stairways and mezzanine level integration seems more work IMO. None of this would be valid for a station like Grand Central. Just 5th and TS really. My second thought from the engineering perspective is POF (points of failure) Door operation of both sides at a non-terminal might be an added level of complexity for something to go wrong more delays for thru service. Just thinking out loud. But I see your point make sense from a dynamics pov just all the other dimensions along with that makes it hard to tell if it could work or not. Why didn't the IRT use this system or if they did how did it work out? Most of the original terminals built by the IRT were done so in the Spanish solution style. If I recall correctly, the only true terminal that did not have this feature was New Lots Av. As for when they stopped using the side platforms, I cannot say, but I believe their use fell out of favor before unification. In regards to expanding the platforms or building new ones at Times Square, remember that the line there is beneath so much real estate that it would be quite the expense to support the structures above. 29 minutes ago, Wallyhorse said: The are a couple of big differences with the over the 1. The stations can be lengthened to 600 feet (and in most cases, that is only a 65-foot or so extension because those stations were built to handle eight-car trains of BMT Standards that were 67 feet in length and as a result albeit with a tight fit could actually handle nine-car trains as it is. 2. The would NOT have to make a curve to reach the Hudson as it's already straight on 14th. Then there is the fact the transfers to literally every major trunk line and gives more riders from NJ an easier time getting to and from NJ. That's why I do the over the to NJ. Not that I'm advocating for it, but curving the Flushing line westward to reach the water would be a drop in the bucket expense-wise when the line would still have to cross the wide Hudson River. I don't think that last mile would be a deterrent if the powers that be were really interested in sending the to New Jersey. Link to comment Share on other sites More sharing options...
T to Dyre Avenue Posted March 6, 2018 Share #129 Posted March 6, 2018 20 hours ago, CenSin said: I wonder if the Spanish solution would be feasible for those currently island platforms. Save the island platform for exiting, and add side platforms for boarding. Or possibly the “Bowling Green” solution, where you add one side platform which handle traffic in one direction, while the island platform would then handle traffic solely in the other direction. 22 hours ago, RailRunRob said: Indeed you may be entirely correct I didn't overlook the possibility of overcrowding I don't have any numbers or stats besides what's in the 5-year-old feasibility report they covered some of the circulation improvements from GC to TS new walkways, stair widening etc. That indicated that those upgrades should be able to handle what they're expecting in additional ridership. This is for the of course. There are so many variables and this is why the new study is important. Again smarter people than us both agree as well. I tend to think and process in probability. So applying 1st principles and what I know to be true. tho IRT standard does serve higher impact areas. Hudson Yards, East Midtown and LIC all areas of major growth in the coming decades. So that puts riders west of the Hudson in a two-seat range of these areas That would at least in my mind put it over the . As for PATH what would be a comparable alignment into Midtown? The NJ side is easy for both but the PATH prob more so being under the FRA arm of things. But Manhattan is humdinger 57th crosstown? 49th? deep level? The transfers and above ground punch throughs are going to be tough alot of displacement, inconvenience, and existing infrastructure. At the very worst case widening the platforms on the Flushing line tho it would be a challenge, GC comes to mind. I don't think it would come to close to a crosstown PATH route in my mind in cost. The at Hudson Yards is already halfway there. And it's a reverse commute for the most part from NJ with overlap from HY to CG same thing we already see on the Lex from 59th to BB. This study should give us a more comprehensive comparison of all options then you narrow down the field. Wouldn’t adding new staircases and widening existing ones reduce platform space? Then you’d really need to add side platforms. Yes, it’s true that the hits the busiest of busy areas by directly stopping at Times Square and Grand Central - the number one and two busiest subway stations in the entire system - as well as the (quickly) up-and-coming Hudson Yards and Long Island City. But Union Square, 6th Ave and 8th Ave on the are no slouches in the ridership department either, especially Union Square, which is a very popular destination day and night. Flatiron, Chelsea, the Village and the Meatpacking District aren’t too far away either. Link to comment Share on other sites More sharing options...
bobtehpanda Posted March 7, 2018 Share #130 Posted March 7, 2018 16 hours ago, CenSin said: With the adding of side platforms though, less of the tunnel has to be widened, reducing the cost. Widening the island platform would mean moving the tracks and the supports as well. I’d like to think that what Hoyt–Schermerhorn Streets would be a better setup than having everyone mix on a single island platform. The Spanish solution works well when traffic in both direction of travel is simultaneously utilized and passenger flow needs to be separated (getting on versus getting off). But when it is used at the terminals (such as in the Bronx), where passengers primarily board in the morning and get off in the evening, some platforms won’t be used. I don't necessarily buy that. The ADA makes building these new platforms and their connections out very expensive; we now have to triple the amount of elevators to the platforms, triple the escalators, triple everything. Most places do not build Spanish solution in the modern day for these reasons. 14 hours ago, RailRunRob said: I'm with you that's an option. From an engineering vantage point let's say Times Square if I needed an additional 7 feet added to the Platform pushing the walls out 4 feet on either side structurally in my mind would be a bit easier. Weight distribution could be done beam section by beam section. In fact, you may be able open the station abit more by redistributing weight via bigger beams and stronger supports just beyond the walls. Think 21st-Queensbridge. You could taper the platform at it ends to line up with the existing tunnel alignment. Digging side platforms would still demand beam alignment to be altered. Digging 8-10 feet out on both sides is way more daunting than a 3-4 foot push what's above me is now more important than ever then add stairways and mezzanine level integration seems more work IMO. None of this would be valid for a station like Grand Central. Just 5th and TS really. My second thought from the engineering perspective is POF (points of failure) Door operation of both sides at a non-terminal might be an added level of complexity for something to go wrong more delays for thru service. Just thinking out loud. But I see your point make sense from a dynamics pov just all the other dimensions along with that makes it hard to tell if it could work or not. Why didn't the IRT use this system or if they did how did it work out? I don't know if it would be so cheap. The is already super deep and supports quite a lot on top of it. If PATH were to hypothetically dig a new tunnel, the best option would be 57th; easy transfers to every trunk, relatively little in the way. Station disruption doesn't actually have to be very disruptive; Barcelona used TBMs to fully enclose the stations as well, so that you would only need to dig access shafts. Link to comment Share on other sites More sharing options...
RailRunRob Posted March 7, 2018 Share #131 Posted March 7, 2018 19 hours ago, Lance said: In regards to expanding the platforms or building new ones at Times Square, remember that the line there is beneath so much real estate that it would be quite the expense to support the structures above. 8 hours ago, bobtehpanda said: I don't know if it would be so cheap. The is already super deep and supports quite a lot on top of it. Points well taken. I was doing some reading on the construction of the Flushing level. It's kinda unique eastern end supports quite abit with the 7th and Broadway lines it's about 6 stories down. And the western end is tube. It should be possible to redistribute some of that weight along some cross sections. But with that said that's coming with a major level of intricacy and cost not sure were that feasibility line is associated with cost so there's truth there. 8 hours ago, bobtehpanda said: If PATH were to hypothetically dig a new tunnel, the best option would be 57th; easy transfers to every trunk, relatively little in the way. Station disruption doesn't actually have to be very disruptive; Barcelona used TBMs to fully enclose the stations as well, so that you would only need to dig access shafts. Interesting... and that makes sense strategically with 57th street. That could work. 16 hours ago, T to Dyre Avenue said: Yes, it’s true that the hits the busiest of busy areas by directly stopping at Times Square and Grand Central - the number one and two busiest subway stations in the entire system - as well as the (quickly) up-and-coming Hudson Yards and Long Island City. But Union Square, 6th Ave and 8th Ave on the are no slouches in the ridership department either, especially Union Square, which is a very popular destination day and night. Flatiron, Chelsea, the Village and the Meatpacking District aren’t too far away either. True I was thinking the new and expanding Business District but you make a good point. Plus PATH cut's some of these areas already. Link to comment Share on other sites More sharing options...
RailRunRob Posted March 7, 2018 Share #132 Posted March 7, 2018 16 hours ago, T to Dyre Avenue said: Wouldn’t adding new staircases and widening existing ones reduce platform space? Then you’d really need to add side platforms. True.. I might have misstated the widening it's more along the lines of exit/entrance from Mezzanine to the street being widened and more entrances overall. But your correct in thinking about those choke points along the platforms with widening. Link to comment Share on other sites More sharing options...
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