GO Transit: Davenport Diamond Grade Separation | ?m | ?s | Metrolinx
- Thread starter vic
- Start date
max
Active Member
Yo dawg, I heard you like pre-tensioned concrete guideway spans...
EnviroTO
Senior Member
I don't really get this bridge installation method. I understand the first gantry crane on rail combo that unloads from truck and puts it up on the first part of the bridge, but from there it seems like the final lift into place via the launcher requires some rather permanent structures rather than a something portable that can slide / drive to the next position. It seems like the launcher will need to be built and torn apart after each use. When I see a metal structure able to handle the load of two concrete spans, I can't help but wonder if building a metal bridge to be the bridge for the bridge segments makes sense when it seems like they could have built the metal bridge to be the bridge for the trains.
Seems needlessly complex... like burning natural gas to get oil out of sand to be refined to make fuel, when the natural gas could have been the fuel.
Seems needlessly complex... like burning natural gas to get oil out of sand to be refined to make fuel, when the natural gas could have been the fuel.
crs1026
Senior Member
^ When I rolled by on the GO Train today, I observed that two of the highway floats that haul the sections to Wallace had been placed atop the in-place spans. I guess that’ts how the spans are moved down the guideway to their installation point.
Personally I think the device is ingenuously clever - the lifts are much less complicated than if craning had to be placed all down the route, and the overhead portion just leapfrogs along.
- Paul
Personally I think the device is ingenuously clever - the lifts are much less complicated than if craning had to be placed all down the route, and the overhead portion just leapfrogs along.
- Paul
EnviroTO
Senior Member
I agree that the first two components make sense. Lift the segments from truck onto the SPMT using a gantry crane on rails, and drive the loaded SPMT down to the end of the already completed bridge. That part keeps working without any repetitive tear down and rebuild. The part that seems cumbersome is the launcher which doesn't seem to move itself.
crs1026
Senior Member
By “launcher” you mean the top lengthwise I-beam structure that the upper crane rides on?
It assume it is self-advancing. Granted, they have to assemble an upright that is bolted to each pair of piers, and disassemble that afterwards, so that’s one assembly and disassembly for each section that they advance over… but it appears to be a pretty simple bolt-and-unbolt affair.
- Paul
ProjectEnd
Superstar
Aplus23
Active Member
Sorry for my ignorance, but where does this go line start and finish? What was in place before, and why is this needed now??
I just like transit construction, I don't know much about transit outside of Scarborough tho
I just like transit construction, I don't know much about transit outside of Scarborough tho
AHK
Senior Member
The Barrie GO line goes from Union Station in Toronto to the Allandale Waterfront station in downtown Barrie. The Barrie line crossed the CP Railway mainline at a ground level intersection in Toronto. The result was that whenever there was a freight train occupying the intersection, the GO train, with all its passengers, had to sit and wait until the freight train had moved out.
This was a bigger problem than might have otherwise been the case, as the freight trains at the intersection (the diamond) were usually very slow moving, or even stopped for periods of time, waiting to get into the CP yard area, south of the St. Clair stock yards.
The impact on GO service to and from the stops on the Barrie line was so severe that Metrolinx has funded creation of an overpass for the Barrie line, over the CP line, to eliminate the problem - the Davenport diamond grade separation project.
Aplus23
Active Member
generalcanada
Active Member
theyre currently working on 1 of the 2 future rail tracks going over CP's tracks.
I know this contractor will build the 2nd overpass after the first is completed, but not sure if they are doing the tracks as well on the 2nd overpass
Can anyone pipe in on that?
tsm1072
Active Member
I believe the majority of the guideway is being built ready for both tracks from the start. There is only a small section (I believe on the North end) that will only be single track and then expanded to double track width once the single track is diverted from the current temporary location to its permanent location on the guideway. I don't believe the double-tracking across the guideway is part of this contract. It will be done on a separate contract after the guideway is complete.
crs1026
Senior Member
^The contract is to complete a full, double-tracked guideway with grades at both ends.. The plan to place one track in service at a time is simply a means to simplify the construction, given the fairly tight confines of the site.
Initially, both the north and south end ramps will be build to a single track width, and then widened after the first elevated track is in service. Both sides of the guideway are being erected together, but the track on the east side will wait until the existing track at grade is removed and the end ramps can be widened.
This is simply a matter of staging the construction efficiently.
- Paul
Initially, both the north and south end ramps will be build to a single track width, and then widened after the first elevated track is in service. Both sides of the guideway are being erected together, but the track on the east side will wait until the existing track at grade is removed and the end ramps can be widened.
This is simply a matter of staging the construction efficiently.
- Paul
Toolio555
New Member
Been reading this forum for quite a while and am a resident in a nearby building. One thing I can say is when I moved in last spring there was nothing and within a year they built all of this. They were working day and night. Now it seems like the construction pace has slowed down. I am not sure if they are just trying to stretch the job for it to be delayed (usual construction mafia behaviour) or what? All I know is they better hurry up and make sure this thing and at grade tracks are removed by 2023 as planned as the loud war like noise from the trains metal wheels hitting the metal track crossing is unbearable. Ridiculous that they even built condos here before this project was completed. I’m sure the residents living here before me have been suffering much longer.
crs1026
Senior Member
I would challenge your statement that the work has slowed. Some stages of construction require a hundred workers and machines, some require only ten. If you see less activity, it’s because many of the tasks are complete and others.can’t be done until other tasks are finished. To my eye, there is no part of the project that is seriously delayed - although the placing of the guideway segments may be happening slower than the announced plan. Other tasks may be languishing because they are timed around that activity.
End ramps are coming together well, the span over the CP tracks is ready, the piers and end walls are poured, the Bloor bridge is halfway complete. The underpasss at Paton is shaping up. Roadbed is being prepared for the track shift at the south end of the zone.
From the GO train, I noticed some puzzling further work along the to-be-elevated section: , the footings of some of the piers has been reexcavated, a foundation some sort of electrical or telco substation has been poured at the south end of Campbell Park. I wonder what all that is about.
- Paul
PS - yeah, the clatter of the diamond is annoying, as it has been since the 1880’s. It’s one of the few remaining, however. The big picture is trending in the right direction.