[Eug]

The Star: Tunnelling beneath Eglinton Ave. for the Crosstown LRT

The Star took a rare trip Tuesday down into the unfinished Eglinton Crosstown tunnel.

 

[Tulse]

In order to use tunneling, the bore must be extra deep to ensure no cave in during construction and minimize the load on the tunnel from traffic above.

I'm no expert, but I would presume that depth also avoid a lot of reworking/rerouting of water/sewer/power infrastructure that would be disrupted by cut-and-cover.

And as someone who works on Eglinton, I can't imagine what it would be like to deal with cut-and-cover along the length of the street. Disruption to travel and the local businesses has been bad enough with the various traffic rerouting -- if the whole street was torn up, I would imagine that many businesses would be wiped out.

 

[M II A II R II K]

It's too bad they don't open the tunnelled section first before the at grade sections are finished.

 

[robmausser]

It's too bad they don't open the tunnelled section first before the at grade sections are finished.

The at grade sections will actually be completed before the tunneled ones. Thats how long tunneling takes compared to at grade construction. Go look at the ION LRT in kitchener that started work in 2015, and is further along than the tunnelled Eglinton section which started in 2010

 

[johntauren]

The at grade sections will actually be completed before the tunneled ones. Thats how long tunneling takes compared to at grade construction. Go look at the ION LRT in kitchener that started work in 2015, and is further along than the tunnelled Eglinton section which started in 2010

But they haven't even started the at grade sections yet.

It's the stations that take the longest, see the Spadina extension which is still a while from completion but tunneling was done a while ago.

 

[cplchanb]

well it will all depend on the how exotic they want the final station designs to be. If theyre simple and more or less cookie cutter, we they can be built quite quickly with smaller chances of unforseen delays.
Now on the other hand if they decide to go fancy on their final designs, it might turn out like the YUS Ext.

 

[BurlOak]

I'm no expert, but I would presume that depth also avoid a lot of reworking/rerouting of water/sewer/power infrastructure that would be disrupted by cut-and-cover.

And as someone who works on Eglinton, I can't imagine what it would be like to deal with cut-and-cover along the length of the street. Disruption to travel and the local businesses has been bad enough with the various traffic rerouting -- if the whole street was torn up, I would imagine that many businesses would be wiped out.

But the disruption mid-block would be a matter of weeks to a month, and it would be one segment at a time. Not a continuous closure of the entire Eglinton. We have precast, prestressed concrete now which did not exist when the other lines were built in Toronto. It would also significantly reduce the construction at the intersections.

 

[crs1026]

I suppose it would depend on just how much stuff is buried under the street - water mains, sewers, telecom, hydro, gas, etc. With tunneling, one only has to worry about those things where the stations are. With cut and cover, you'd be uncovering and potentially replacing all of it, end to end... and every building occupant would be impacted by sewer closures, water cutoff, etc. Coordinating all those services is a major undertaking, too.

I'm a bit dubious that it would only be a month's impact. Certainly it could be done, but I bet it would be more complicated and more costly than it sounds.

- Paul

 

[Palma]

The at grade sections will actually be completed before the tunneled ones. Thats how long tunneling takes compared to at grade construction. Go look at the ION LRT in kitchener that started work in 2015, and is further along than the tunnelled Eglinton section which started in 2010

tunnelling did not start in 2010, it started in 2013

 

[Steve X]

And here's Laird Station: http://thecrosstown.ca/news-media/whats-new/laird-station-open-house

The one main difference you'll see is that Laird is mined unlike Keele and Eg West. Also we'll see Keele Station's structure complete in 2019 while they start Laird in 2019. Mined station wouldn't require the entire length of the station box to be dug up oppose to cut and cover.

Also, don't compare this with the ION. That's an LRT and this is an actually subway. The on-street LRT section doesn't start till 2018 and would end in 2021 (only 3 or so years).

 

[Markster]

Also, don't compare this with the ION. That's an LRT and this is an actually subway. The on-street LRT section doesn't start till 2018 and would end in 2021 (only 3 or so years).

@robmausser was comparing subway construction to surface construction. That was the whole point, to say that the surface construction for Eglinton will be faster than the subway construction for Eglinton. ION is an in-progress example of surface construction.

 

[robmausser]

@robmausser was comparing subway construction to surface construction. That was the whole point, to say that the surface construction for Eglinton will be faster than the subway construction for Eglinton. ION is an in-progress example of surface construction.

Thanks for backing me up, some people on this forum are of such densities that I have a better time talking to a piece of hardwood.

 

[Markster]

...not that it needed to be followed up with insults.

 

[Dan416]

They should really put the cross street in brackets or something for these station names. When I look at the maps with the new names I don't know where they are. I feel bad for anyone trying to find Yonge Street on the new map. I hate to keep harping on it but it drives me crazy and makes me angry lol.

 

[W. K. Lis]

I know where St. Andrew and St. Patrick stations are NOW. When they first opened, it took a few trips to get my bearings. And the smaller font street names under the station names.