[U/C] M2 North-South Motorway

[fishinajar]

The big drawback with tunnels and trenches is that, in the future when demand has increased and the road has reached capacity, they cannot be easily widened to accomodate extra lanes. So it is deirable that you make them extra wide to future proof them. For that reason, 6 lanes for the inner city section is a must.

This is the dilemma with the Gallipoli Underpass.

I thought I read somewhere it was possible to squeeze anther 2 lanes out of the Gallipoli underpass? If not then definitely a big fail in its original design. Still there is plenty of room to widen the trench at this point.

We don't necessarily need or want greater capacity in the serviceable future. The 30yp is promoting more infill development, more pt usage, and we have autonomous vehicles on the horizon. Getting better flows through the central section of the corridor will also increase the flow further out.

[alexczarn]

The big drawback with tunnels and trenches is that, in the future when demand has increased and the road has reached capacity, they cannot be easily widened to accomodate extra lanes. So it is deirable that you make them extra wide to future proof them. For that reason, 6 lanes for the inner city section is a must.

This is the dilemma with the Gallipoli Underpass.

Also on the Nth-Sth Mwy the northbound section drops to 2 lanes just before the 2 lanes join from Grand Jctn Rd. That will end up being a big bottleneck with the Northern Connector.

[Mr Messy]

The big drawback with tunnels and trenches is that, in the future when demand has increased and the road has reached capacity, they cannot be easily widened to accomodate extra lanes. So it is deirable that you make them extra wide to future proof them. For that reason, 6 lanes for the inner city section is a must.

This is the dilemma with the Gallipoli Underpass.

Also on the Nth-Sth Mwy the northbound section drops to 2 lanes just before the 2 lanes join from Grand Jctn Rd. That will end up being a big bottleneck with the Northern Connector.

That part was designed so they could change it to 3 lanes at a later date

[ChillyPhilly]

The big drawback with tunnels and trenches is that, in the future when demand has increased and the road has reached capacity, they cannot be easily widened to accomodate extra lanes. So it is deirable that you make them extra wide to future proof them. For that reason, 6 lanes for the inner city section is a must.

This is the dilemma with the Gallipoli Underpass.

I thought I read somewhere it was possible to squeeze anther 2 lanes out of the Gallipoli underpass? If not then definitely a big fail in its original design. Still there is plenty of room to widen the trench at this point.

Maybe by widening the cut to the west. There is some vacant land to the immediate northwest of the intersection as well.

[[Shuz]]

They definitely stuffed up Gallipoli Underpass design. 3 lanes at 80kph cannot fit without any shoulders for emergencies and an extremely narrow median.

[rhino]

They definitely stuffed up Gallipoli Underpass design. 3 lanes at 80kph cannot fit without any shoulders for emergencies and an extremely narrow median.

In Shuz's opinion

[alexczarn]

They definitely stuffed up Gallipoli Underpass design. 3 lanes at 80kph cannot fit without any shoulders for emergencies and an extremely narrow median.

ITS would partially solve the no shoulder problem.

[Brucetiki]

They definitely stuffed up Gallipoli Underpass design. 3 lanes at 80kph cannot fit without any shoulders for emergencies and an extremely narrow median.

ITS would partially solve the no shoulder problem.

Assuming Adelaide motorists obey the ITS.

[Bacon]

They definitely stuffed up Gallipoli Underpass design. 3 lanes at 80kph cannot fit without any shoulders for emergencies and an extremely narrow median.

Heysen Tunnels don't have a much shoulder, I drove the M5 tunnel (80kph) and it has zero shoulder. But what it does have is more intensive monitoring.

[drsmith]

The Gallipoli Underpass looks like it has a width of 21m between the side barriers. That's enough for 6x3.5m lanes but without any shoulders or space for a central barrier. Narrowing the lanes to 3.4m would provide 600mm of space for a central barrier but the complete lack of shoulders may mean the underpass would have to operate at a lower speed limit than the future expressway either side. That's probably not a good idea either.

The underpass may operate OK for some time in a 4-lane configuration for some time after the route either side is built to 6-lane expressway standard due to lower traffic volumes on the road section under the bridge.

[SouthAussie94]

If the motorway to the north of ANZAC Hwy is going to be trenched, then it's likely the Northern ramp of the underpass will need to be reworked. Assuming the motorway is also trenched to the South, this ramp would also need to be reworked.

These reworked sections could be made wider, leaving only a relatively short 400-500m section that is narrow with no shoulders.

Does anyone have an estimate of how wide the cladding on the walls of the underpass is? Removing this could add another few hundred mm's.

[ChillyPhilly]

If the motorway to the north of ANZAC Hwy is going to be trenched, then it's likely the Northern ramp of the underpass will need to be reworked. Assuming the motorway is also trenched to the South, this ramp would also need to be reworked.

These reworked sections could be made wider, leaving only a relatively short 400-500m section that is narrow with no shoulders.

Does anyone have an estimate of how wide the cladding on the walls of the underpass is? Removing this could add another few hundred mm's.

Surely it will be reworked. When driving in either direction along there, the gradient never really feels suitable for 80 km/h, let alone the proposed design speed of 90 k's.

Here's the spare land:

[SBD]

How wide is the final width of the T2T trench for comparison? The current bike lane could be sacrificed to the third motor vehicle lane, as the plan appears to only permit bikes on the surface lanes of the non-stop motorway, and not included in all artist impressions. I would still feel uncomfortable driving against the wall with a semi-trailer or B-double in the 2nd lane next to me, but it is possible I will dislike that in any of the trenched sections.

[Llessur2002]

They're laying asphalt along both sides of Port Road leading up to the new bridge in preparation for putting the road back from whence it came.

It's nice to see that the footpaths around this intersection have been widened considerably as part of the works.

[rockthenation]

Does anyone know if that derelict looking building next to Croydon Motors near the corner of South Rd & Hawker St is being demolished?
The front verandah was removed from it a few months back but nothing since then.


Sent from my iPhone using Tapatalk Pro