CROSSTOWN LRTConstruction Liaison

CommitteeJune 14, 2017

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Agenda

• Leaside Station Update

• Laird Station Update

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Leaside Station Concept: Aerial View

Main Entrance

Secondary Entrance

*60% rendering

Accessible Entrance

Accessible Entrance

Outdoor bicycle parking

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Leaside Station: 2016 in Review

• Demolition at 1787 Bayview Ave completed

• Median Removals & temporary traffic signals installations

• Utility relocations (hydro & telecommunications), underway or complete

• Support of excavation (shoring) work started at Main Entrance

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Year Quarter Construction Activity / Closure

2017

Q1

(Jan-March)

• Bell, hydro and other telecom utility relocations

• Support of excavation (shoring) underway at Main Entrance

• Stage one for support of excavation activities in right of way

(work will be completed in 4 stages)

Q2

(April-June)

• Stage one ongoing

• Drill to move to Secondary Entrance in late June/early July

• Temporary Site Service Connections (hydro)

• Dewatering System Installation

Q3

(July-Sept)

• Stage one B

• Stage two support of excavation activities in right of way

Q4

(Oct-Dec)

• Stage three of support of excavation activities in right of way

Leaside Station: What to Expect in 2017

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How We’re Building Leaside Station:

Support of Excavation

• Shoring is a common step in the process of installing the foundation of a building.

• In the first stage, an area the size of the station’s footprint (about 100m x 20m) will have steel piles installed around the perimeter. Then a shallow area is excavated and braces and tie-backs are installed around the sides to support the excavation.

• Decking is then placed over the excavation to allow the crew to work under the roadway safely while traffic flow resumes above.

• The shoring stage at Leaside Station started in January and will take approximately 15 months to complete.

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How We’re Building Leaside Station:

Excavation and Mining

• During the excavation, crews continue to work

safely beneath the roadway.

• At Leaside Station a section of the station box

will also be mined during this time.

• With the mining method, the underground

area to be excavated is divided into

manageable segments and the segments are

excavated in a planned sequence.

• The excavation creates a shotcrete-lined

cavern underneath Eglinton Avenue East.

Within the cavern, the station box is

constructed accommodating the rail tunnels,

associated platform and rail infrastructure.

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Support of Excavation (shoring): Station Box

Mined Area

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Support of Excavation (shoring): Stage One

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Proposed Stage 1B

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Proposed Stage 2

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Progress Picture – Main Entrance

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Progress Picture – Station Box

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Laird Station Concept: Aerial View

Main Entrance (accessible entrance)

Secondary Entrance

*60% rendering

S

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How We’re Building Laird Station:

Support of Excavation

• Laird Station will be constructed using a mined method known as Sequential Excavation Method or SEM. The first stage is support of excavation.

• Support of excavation (shoring) is a common step in the process of installing the foundation of a building.

• In the first stage, crews will install steel piles around the perimeter of the entrance. This has been completed at both entrances.

• In the second stage, crews excavate the area level by level, installing braces and tie-backs as they progress. This work is underway at the main entrance.

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• Mining occurs from inside of the excavated entrances after the support of excavation is complete. This work now underway at the secondary entrance.

• The underground area to be excavated is divided into manageable segments and the segments are excavated in a planned sequence.

• Within the mined area, the station box is constructed accommodating the rail tunnels, associated platform and rail infrastructure.

• Laird station has one of the longest station areas with approximately 500m to be mined. This is to accommodate special track to store a LRV between the tracks or for an LRV to change direction in the event of a service disruption.

How We’re Building Laird Station:

Sequential Excavation Mining Method

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Laird Station: 2016 in Review

• Geotechnical Investigation completed

• Demolition at 250-256 Laird Drive completed

• Utility relocations (hydro & telecommunications)

• Piling work completed and excavation work started at both entrances

• Temporary traffic signals installations17

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Year Quarter Construction Activity

2017

Q1 (Jan-March) • Site Service Connections - Completed

• Excavation (shoring) underway at Main (underway) and

Secondary entrance (completed)

• Long-term closure at Main entrance – in place

Q2 (April-June) • Crane erection secondary entrance – completed

• Mining operations at Secondary entrance - underway

• Dewatering System installation - underway

• Concrete pour into tunnels - underway

• Utilities protection

• Gas Main Support - underway

• Sewer Lining - upcoming

• Crane erection main entrance – upcoming

• Excavation ongoing at Main entrance

Q3 (July-Sept) • Ongoing mining operations at Secondary entrance

• Start of mining operations at Main entrance

Q4 (Oct-Dec) • Mining continues at both entrances (mid 2017 to late 2019)

Laird Station: What to Expect in 2017

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Laird Long Term Closure

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Support Works – Utilities Mitigation

What to expect: Sewer Lining

• Sewer lining is a process intended to increase the durability of the sewers.

• A section of the sewer system is cleaned and vacuumed and a CCTV inspection is completed. Then a liner is inserted into the sewer section from within the maintenance holes

• The process is designed to be generally non-disruptive and eliminates the need for excavation of the entire sewer section.

• Maintenance holes that will be accessed are located on Eglinton Avenue East between Sutherland Drive and Brentcliffe Road.

• Lane closures will be required for this work. Pedestrian access will be maintained.

• Above ground pipes will be in place between maintenance holes to bypass pump around the sewer lines during the liner installation.

• Due to the nature of the work, an unpleasant chemical odour may be noticeable in the vicinity of the maintenance holes and, in some circumstances, in the home. It is not harmful, however it can be limited by covering floor drains while the sewers are being lined.

A public notice with additional details will be distributed prior to work beginning.

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Support Works – Utilities Mitigation

What to expect: Sewer Lining

Sewer Lining Activity Examples

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Progress Picture – Main Entrance

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Progress Picture – Secondary Entrance

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Local Area Map

Station(s) under construction

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Community Benefits – Laird Mural

• Creation of a mural that reflects the Thorncliffe Park neighbourhood

• Design concept under development

• Production/painting is scheduled for the first week of July (July 4-7)

• Feedback welcome!

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