10-29-2022, 08:59 AM
(10-29-2022, 07:57 AM)danbrotherston Wrote:(10-28-2022, 06:14 PM)KevinL Wrote: The reason we don't have centre platforms at the two termini is because in both cases, the end of the platform was too close to a cross street to allow the width of crossover tracks required; going with side platforms shortened the crossovers enough to fit.
I'm not sure I fully understand this. Why can't the crossover occur in the intersection? Or...beyond the intersection? TTC has switches IN the intersections all the time.
Those are streetcar switches. Not to say that it’s impossible to do, but it’s a specialized arrangement and in general I believe railways avoid putting points in level crossings. I’ve actually seen the avoidance of points in a level crossing given as a justification for gauntlet track: the points can be on one side of the level crossing, then gauntlet track can take both tracks, overlapped with each other, through the level crossing, then finally the tracks can diverge on the other side. You’re right though that putting the crossovers immediately the other side of the level crossings shouldn’t be a big problem.
That being said, I say to the previous poster, “cite please”. While it is true that the crossovers at both sites are quite near to the closest level crossing, a casual glance at the aerial photography suggests multiple approaches to accommodating centre platforms. Unless there is a source from within the project team about their specific reasons for the design, their explanation is just supposition.
To be fair, the same applies, at least in principle, to my observation about the TTC subway terminus platforms; but in that case the consistent policy of always building center platforms at stations intended to be permanent termini, as well as their usual mode of operation requiring the use of both tracks, provide strong support that the reason I give is indeed the reason.