Steve X
Senior Member
It will have to be cut and cover or mined. Mount Dennis Station isn’t that deep under so there’s no way they can even think of TBM.
- Thread starter W. K. Lis
- Start date
ARG1
Senior Member
I'm pretty sure its already been confirmed to be dug using a TBM.
smallspy
Senior Member
They've only confirmed that there will be a tunnel, not what will be used to create it.
Dan
ARG1
Senior Member
Request for Proposals Issued to Shortlisted Teams for Advance Tunnel Contract 2 on the Eglinton Crosstown West Extension
Infrastructure Ontario (IO) and Metrolinx have issued a Request for Proposals (RFP) for the second Advance Tunnel Contract (ATC2) for the Eglinton Crosstown West Extension (ECWE). This 500-metre tunnel will start east of Jane Street and connect to the future Mount Dennis Station.
So I presume its up to the winning bidder to determine how the tunneling will be done?
TheTigerMaster
Superstar
Moles? Groundhogs? Enormous worms? We have lots of tunnel digging options.
smallspy
Senior Member
Without having intimate knowledge of the wording of the tender, that would be my assumption.Request for Proposals Issued to Shortlisted Teams for Advance Tunnel Contract 2 on the Eglinton Crosstown West Extension
Infrastructure Ontario (IO) and Metrolinx have issued a Request for Proposals (RFP) for the second Advance Tunnel Contract (ATC2) for the Eglinton Crosstown West Extension (ECWE). This 500-metre tunnel will start east of Jane Street and connect to the future Mount Dennis Station.www.infrastructureontario.ca
So I presume its up to the winning bidder to determine how the tunneling will be done?
It would be a bit unusual to use a TBM for such a short distance, especially considering that the launch and retrieval pits will end up requiring almost as much distance as the length of the tunnel itself. It seems to me that this short length would be ideally suited for cut-and-cover - especially considering that the east end of the tunnel/west end of Mount Dennis Station is only covered by a couple of feet of cover. Another likely option would be to mine the tunnel as the set up costs are considerably lower than using TBMs even though the ongoing working costs are higher.
Dan
Steve X
Senior Member
I believe there is a safety requirement on how deep the TBM needs to be before being used. That’s something like at least twice the diameter. If they just used it in shallow condition like this tunnel, all the houses will feel the vibration that can possibly knock them down.
fanoftoronto
Active Member
That's fair enough. I think it's safe to say this tunnel will be built in a cut-and-cover method. Though, from the Design Plates in the Environmental Assessment, it calls 300 metres of this section as a "Bored Tunnel". Please help! My brain cannot comprehend!
smallspy
Senior Member
"Bored" would imply that they are digging out the tunnel sequentially from one or both ends, as opposed to digging a trench and covering over it - the colloquial "cut-and-cover".
A TBM is one way to bore a tunnel, but by no means the only way.
Keep in mind too, that they don't have to follow the exact drawings as presented in the EA, but just to use them as a guideline. I don't know if changing from a bored tunnel to cut-and-cover would necessitate a fresh EA - others here will be able to answer that better than I.
Dan
Northern Light
Superstar
Its always encouraging to see one's Elected Representatives using their time wisely to bring important issues to the fore...... Cough
Councillor Nunziata has put an urgent member motion before Council asking Metrolinx to bury the elevated portions of the proposed Line 5 extension.
Councillor Nunziata has put an urgent member motion before Council asking Metrolinx to bury the elevated portions of the proposed Line 5 extension.
Allandale25
Senior Member
^ I like Matt's "physics-bending" description.
Amare
Senior Member
When does she retire again? The sooner the better really.
EnviroTO
Senior Member
A motion should be put in place to have trains depart before they arrive. It is a simple scheduling adjustment you can make in any spreadsheet. Who wants to wait?
sixrings
Senior Member
Bury it all the way to square one.
fanoftoronto
Active Member
Let's also bury the elevated or at-grade sections of all the other lines as well while we're at it.
Line 1 - Goodbye to the surface sections between Rosedale - Eglinton stations, and the section in between Allen Road.
Line 2? Phew, so many! Kipling to Royal York above ground sections need to be buried immediately!! Also, Old Mill station being above ground at Humber River? Preposterous! Put it deep underground, under the river!!!! Don't even come to me about the sections between Runnymede and Dundas West stations. Bury bury bury! On the east side, I don't think we can accept the line being above ground at the Prince Edward Viaduct, we need to put it all underground, beneath the Don Valley! And how dare the trains can even think of being exposed to sunlight between Victoria Park to Warden stations!
Line 3? Good planning by the power that be, by turning the elevated SRT into the far superior, deep underground, subway. Screw the money!
I think we have to go one step further and bury even the Maintenance and Storage Facilities! These subway trains should not be allowed to see sunlight when they are in service with the TTC!
Should we also let Councilor Nunziata know about all the GO tracks that are above ground?
/s
God, sorry everyone, I had to get that off my chest!
Line 1 - Goodbye to the surface sections between Rosedale - Eglinton stations, and the section in between Allen Road.
Line 2? Phew, so many! Kipling to Royal York above ground sections need to be buried immediately!! Also, Old Mill station being above ground at Humber River? Preposterous! Put it deep underground, under the river!!!! Don't even come to me about the sections between Runnymede and Dundas West stations. Bury bury bury! On the east side, I don't think we can accept the line being above ground at the Prince Edward Viaduct, we need to put it all underground, beneath the Don Valley! And how dare the trains can even think of being exposed to sunlight between Victoria Park to Warden stations!
Line 3? Good planning by the power that be, by turning the elevated SRT into the far superior, deep underground, subway. Screw the money!
I think we have to go one step further and bury even the Maintenance and Storage Facilities! These subway trains should not be allowed to see sunlight when they are in service with the TTC!
Should we also let Councilor Nunziata know about all the GO tracks that are above ground?
/s
God, sorry everyone, I had to get that off my chest!