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About engineerboy6561

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  1. engineerboy6561

    February B110 action

    Yup; there's a cruddy Google map screenshot here, and then I made a Google map here based on the assumption that the bus runs via the highway during regular operation; I guess it runs Vanderbilt/Prospect Park/McDonald Av/Ft Hamilton Pkwy when 278 is really bad.
  2. engineerboy6561

    Second Avenue Subway Discussion

    And here's a sample image of that same viaduct loaded up in a four-track configuration, with 12'6" track centers to accommodate B division trains (and a sample B division train placed on it for scale in SketchUp; something like this would be pretty easy to build overtop the Park Av viaduct. Yeah, the MTA is probably bad enough at making the necessary arrangements that this is unlikely, but if we built out structures like this to replace old els on say the or the everyone would be much happier . For reference, the width on this between the widest points is 61'6" carrying four tracks, so you could run it down Roosevelt Av or Jamaica Av/Broadway fairly comfortably.
  3. engineerboy6561

    Second Avenue Subway Discussion

    The pillars on the Dubai metro (what that photo up there is from are about 6-7 feet wide, which is a bit wide to do on some of the older NYC streets where we have elevated lines, especially if we're looking at running three- or four-track lines with 600' trains on each track as opposed to two-track lines running 300' trains (Dubai), and the spacing looks about 100' apart on average. Doing some back-of-the envelope analysis, a single R160 car weighs about 86,000 lbs over a length of 60 feet, so we have a base unit for how much weight a column has to sustain. If we want to assume that we can place columns every 50 feet (as per the standard distance quoted in this reference), and that we can basically assume a viaduct structure that successfully forces all the load onto the columns (which I have to do because I'm an EE and not a structural engineer) the maximum load on a four-track structure between columns would be 43,000lbs*8 (assuming that we can treat the bogies as point loads, and that car weight is split equally between bogies, each car comprises two 43,000lb point loads) because that's equal to a pair of coupled cars passing over each of four tracks at once, and we have a maximum load per segment of 344,000 lbs. According to this engineering calculator here, a cylindrical reinforced concrete column of 30" diameter with eight steel rebars in it is good for about 1.899 million pounds. Assuming you can build a sufficiently rigid structure to transmit the load down to the columns you could probably use a viaduct structure that looks something like this: The specific structure I roughed out here has about 16,320 cubic feet of concrete per bridge segment, and assuming a 145lb/cubic foot concrete density gives us about 2.37 million pounds. If we assume that each support is resting half on one pair of columns and half on the other, we have an average static load of 2.37 million pounds per column pair, which comes down to about 1.185 million pounds per column. If we add the maximum total load of 344,000 lbs to this number, we have a total per-column load of 1.357 million pounds, which gives me about a 29% margin of safety on the columns; I'd love for an actual engineer to chime in and critique this design, but something like this could be relatively easily placed on most city streets that currently carry elevated trains, and could be fairly easily designed for noise and vibration rejection to reduce the noise load on local residents.
  4. engineerboy6561

    Second Avenue Subway Discussion

    The thing is that I think most of the resistance to el-building comes from the idea that they all look like this: when a well-built el looks like this: Now your actual viaduct cross section might look a bit different if you're not building in the median of a limited-access road, but you could probably build something that would be pretty quiet and not piss people off fairly easily.
  5. engineerboy6561

    Second Avenue Subway Discussion

    The thing is that the old els are noisy, dark, and dingy; newer ones don't have to be at all that way; the only spot you'd hit any issues with would be the patch on Park Av between 161 St and 156 St because of the buildings that would have to come down. I'd honestly prefer a four-track trunk under 3 Av from Fordham to 138 St, then under 2 Av down to Houston St, but if the choice is an el over Park or nothing at all let's take what we can get
  6. engineerboy6561

    Redesign a Line

    Honestly, if I were going to do this there are so many things I'd do that they'd take up a full page; the big one, though, would be turning any and all at-grade junctions into flying junctions, and reconfiguring all junctions such that trains didn't ever have to cross in front of each other
  7. engineerboy6561

    Department of Subways - Proposals/Ideas

    What about if instead of building HHE as a local split off of the QBL we built a new line along 495/Flushing Av/Metropolitan Av and connected it to the Second Ave Subway around Houston St?
  8. engineerboy6561

    Trainz NYCTA Videos

    This looks utterly amazing It's good to see you back on here again, and I'd love to talk content creation with you!
  9. engineerboy6561

    Department of Subways - Proposals/Ideas

    It looks like it would be about the same, with only a slight advantage to the . If you assume the tail tracks are under Brewer Blvd, then you have to bring them under the South Jamaica Houses and you could probably get them to connect to the LIRR tracks around 109 Av. From there you're looking at additional stops at 109 Av-ish, Linden Bl, Foch Bl, Baisley Blvd, between 140 Av and 141 Av, and at N Conduit Av to get reasonable stop spacing. You're also going to need to expand the interlocking near Green Acres Mall to allow for all four branches (Babylon, West Hempstead, Far Rockaway, and Long Beach) to fit on those two tracks between St. Albans and Valley Stream. The would require less new track and fewer sharp curves, as you could extend it along Roosevelt and then S-curve it onto the railroad alignment near Parsons. The big things you'd wind up doing that would be expensive are ripping out the mezzanine at the end of the Main St station, and probably lowering the railroad track about 10 additional feet between Main St and Parsons Bl so that you could do a clean merge with the tracks without wrecking anyone's basement. That said, routing the onto those tracks past Flushing seems a bit like a waste of trackage. What I'd personally be interested in doing would be adding infill stops on the PW line at Junction Blvd and Queens Blvd, splitting those two tracks off at the Sunnyside interlocking and running them under Newtown Av to 30 Av, then under the East River to connect with the 2 Av subway at 86 St. At that point you could conceivably run both the and via 2 Av in Manhattan. At that point, the would serve PW and NE Queens, the would serve the Bronx and Harlem, the would serve Forest Hills/71 Av, and the would serve Astoria, with an transfer point at 30 Av/31 St and an transfer at Main St, Flushing (build a proper station house at Roosevelt Av on the railroad and then add a passage under Main St to the ).
  10. engineerboy6561

    Bus Bus NYC

    Great shots! Just out of curiosity, do you know what the deal with the OG hybrid on the QM4 is? Is BP that hard up for MCIs these days?
  11. Would it be possible for you to scan and upload them to the site (or elsewhere) as PDFs?
  12. Agreed. Looking at it it seems like they'd be replacing everything from Palisade Av east, which means closing 495 east of Kennedy Blvd, dumping all that traffic onto 30th and 31 Sts, and then leaving only the Park Av/Marginal Hwy access points. At that point it might make sense to make the tunnel HOV/bus only and run bus bridges to park-and-rides in the area.
  13. engineerboy6561

    Second Avenue Subway Discussion

    I'd go even further and argue that the whole damn thing should have been a four-track trunk line from 125 St to at least 2 Av/Houston St, with twin four-track trunks branching out to serve 3 Av in the Bronx and Astoria Bl in Queens on the north end and some combination of Jamaica (replacement for Jamaica El), Williamsburg/LIE (as I outlined in the post below) and Utica Av down to Kings Plaza on the south end. I still really feel like the city is shooting itself in the foot really badly by building this as an extremely deep two-track line instead of a shallower four-track trunk.
  14. engineerboy6561

    Second Avenue Subway Discussion

    Physically, I think so. I'd assume that you could do it. If you put the 2 Av/Houston St station between Houston and 2nd Sts, then you could do a 1000' radius curve that would end you between Rivington and Delancey; follow it around a little longer and you could slide the line onto Rivington and then drop it down below the Hudson. If you use the existing provisions at 2 Av to build the over the you should be fine because the F drops down further to serve the Delancey St lower level. Just start the descent into the tube a little after Pitt St and you should be fine. According to the NOAA chart for that part of the East River a line from Rivington St to South Fourth St would max out around 60' deep. If you assume the line is about 10' deep when it goes over the near Rivington and Essex, then you can have a station at Pitt St serving the LES/Alphabet City area, and then an 0.4% grade gets you 80' deep on the Manhattan side. On the Brooklyn side, a 1% grade would get you up to probably around 20' below the surface in time to have a Wythe Av stop that could then be followed up with further stops in Brooklyn. If you're below the at 2 Av then this may get more complicated and a stop at Pitt St might be much more difficult and expensive because of how deep you'd need to go.
  15. engineerboy6561

    85 60-Foot Clean Diesel Articulated Buses

    Mostly during rush the runs on the 1 to Journal Square need it badly even if those runs wind up being pullouts and pull-ins. Looking on street view the issue seems to be layover space more than anything else, and there's definitely space to lay over at least one or two artics at 20 St. If that winds up not being enough you could always just take away on-street parking on S 21 St between 16th and 17th Avs and turn artics in a loop around the block bounded by 16 Av, S 20 St, 17 Av, and S 21 St. Fixing the Ivy Hill loop requires removal of one tree and maybe one parking space; just connect the loop to Manor Dr next to the street, and get rid of on-street parking on Mt Vernon Pl between Tuxedo Pkwy and Manor Dr entirely, and you could lay over 3-4 artics there comfortably.


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