ION - Waterloo Region's Light Rail Transit

[Elmira Guy]

I feel like a dolt for having to ask this, but... what exactly is a crossover in the context of LRT?

[danbrotherston]

I feel like a dolt for having to ask this, but... what exactly is a crossover in the context of LRT?

The set of switches that allows trains to switch from one track to the other.

[Elmira Guy]

/\ That's what I thought. Didn't want to assume and be in error though.

Thank you.

[Canard]

Crossovers are used primarily to allow a train to change direction (ie, return to the OMSF prior to making it all the way to Fairway).

[Canard]

I'm surprised it hasn't been mentioned yet, but yesterday they did the final concrete pour for the Cameron Heights crossover!

[tomh009]

I'm surprised it hasn't been mentioned yet, but yesterday they did the final concrete pour for the Cameron Heights crossover!

I forgot to post the photo, sorry!  But it's only the first section poured, two more remain, as I recall.

   

[Canard]

Oops, I meant it's the final pour for the first half of the crossover - then, 8 more welds, then the segments at either end can be poured.

[BuildingScout]

I drove yesterday past the GRH station and they seemed to be drilling yet again on freshly poured concrete at that stop.

[KevinL]

BuildingScout
I drove yesterday past the GRH station and they seemed to be drilling yet again on freshly poured concrete at that stop.

Sounds like the accuracy of platform edges is being taken VERY seriously.

[Canard]

...or they're just doing regular planned work.

[tomh009]

A couple of photos from Duke St today.  There is progress, the curbs are poured, and the roadway is graded, but I can't see that they could open College and Water by the end of October as planned, unless they will just put a steel plate over the (future) embedded track to enable traffic to cross.

   

   

[Pheidippides]

Another unfortunate utility box placement, this time at King and William at the edge of the public square:
   
   

There must be an engineering reason for these types of utility boxes not to have been placed more logically; I mean it can't be the expense of moving them 1m or 2m that's stopping them (especially in the grand scheme of the total project cost).


Question: Wouldn't it be best, at this point, to wait and see if the first train fits the platforms as Bombardier has promised their design will instead of shaving millimetres off everywhere?

[Canard]

No, because engineering is not "trial and error". There's a reason for tolerances. If a company subcontracts the build of their design (as is here) and it's out of tolerance, it's up to that supplier to correct their mistake.

[ijmorlan]

Another unfortunate utility box placement, this time at King and William at the edge of the public square:

There must be an engineering reason for these types of utility boxes not to have been placed more logically; I mean it can't be the expense of moving them 1m or 2m that's stopping them (especially in the grand scheme of the total project cost).

No there doesn’t. They might just not care.

At UW they closed the upper level of the DC-MC bridge for about a year when M3 was built, in order to tie in the M3 bridge. Yes, you heard right, a full year. It is simply not credible that they actually needed to do that — except for removing some of the baseboard heaters and adjusting the floor grade, the work didn’t even touch anything except the wall facing M3. So they could have closed for a couple (OK, I’ll be generous, and say “a few”) weeks to adjust the heaters and the floor, then built construction hoarding to narrow the hallway down for the remaining time required to open up the wall and complete the bridge.

Sometimes the designers just aren’t looking at all the criteria they should be.

Having said that, it is certainly possible that the utility box placement is more constrained than seems obvious.

[Canard]

Sometimes outside observers and "armchair engineers" have no idea what kind of restrictions a designer/engineer was given. It's impossible for any of us to understand or know the dozens of factors that went into why that box is where it is.

If there's one thing I've learned over my 15 year career as a designer it's that no matter what you do, someone's going to be pissed off at you