M1 South-Eastern Freeway

[Norman]

I noticed yesterday when driving through that the new variable speed limit signs in the tunnel and on the approaches are bidirectional, ie they are on both sides of the gantry. You can see this in the renders if you look close enough.

Presumably this is so they can close one tunnel off during and emergency and also when they are doing maintenance and go contraflow.
IMG_4939.pngIMG_4940.png

Interesting, good pick up!

[ChillyPhilly]

Channel 7 and InDaily reporting that a band-aid solution has been devised, with traffic lights to be moved 100m west along Cross Road.

https://www.indaily.com.au/news/adelaid ... ck-crashes

[SouthAussie94]

Why not just install a concrete barrier in the median strip of Cross Rd?

Sure, this wouldn't stop traffic heading west on Cross Rd from being hit by an out of control truck, but neither would moving the stop line for the intersection further east.

[Goodsy]

Why not just install a concrete barrier in the median strip of Cross Rd?

Sure, this wouldn't stop traffic heading west on Cross Rd from being hit by an out of control truck, but neither would moving the stop line for the intersection further east.

There's probably not enough concrete in all of South Australia to build a wall thick and tall enough to stop a runaway truck.


IMO, as a truck driver who descends the freeway once or twice a month, there's nothing that can be done to fix the problem with the intersection in its current configuration.

An arrestor bed wouldn't have saved that last truck from rolling.. He just took the left turn way too fast, could have happened at any other intersection.

I see more smoking brakes going down Grand Junction road towards the Gepps Cross intersection than going down the freeway

[SouthAussie94]

Why not just install a concrete barrier in the median strip of Cross Rd?

Sure, this wouldn't stop traffic heading west on Cross Rd from being hit by an out of control truck, but neither would moving the stop line for the intersection further east.

There's probably not enough concrete in all of South Australia to build a wall thick and tall enough to stop a runaway truck.


IMO, as a truck driver who descends the freeway once or twice a month, there's nothing that can be done to fix the problem with the intersection in its current configuration.

An arrestor bed wouldn't have saved that last truck from rolling.. He just took the left turn way too fast, could have happened at any other intersection.

I see more smoking brakes going down Grand Junction road towards the Gepps Cross intersection than going down the freeway

The existing median is about 2m wide.

A 2m wide, 1m tall barrier would surely be as truck proof as you can get. Obviously wouldn't be great for the poor driver of anything that hit it though.

I guess this just leads to the discussion thats happened countless times in the past. What's the long term plan for the intersection and the freight route from Murray Bridge to Adelaide?

[SBD]

Why not just install a concrete barrier in the median strip of Cross Rd?

Sure, this wouldn't stop traffic heading west on Cross Rd from being hit by an out of control truck, but neither would moving the stop line for the intersection further east.

There's probably not enough concrete in all of South Australia to build a wall thick and tall enough to stop a runaway truck.


IMO, as a truck driver who descends the freeway once or twice a month, there's nothing that can be done to fix the problem with the intersection in its current configuration.

An arrestor bed wouldn't have saved that last truck from rolling.. He just took the left turn way too fast, could have happened at any other intersection.

I see more smoking brakes going down Grand Junction road towards the Gepps Cross intersection than going down the freeway

The existing median is about 2m wide.

A 2m wide, 1m tall barrier would surely be as truck proof as you can get. Obviously wouldn't be great for the poor driver of anything that hit it though.

I guess this just leads to the discussion thats happened countless times in the past. What's the long term plan for the intersection and the freight route from Murray Bridge to Adelaide?

Where did the truck that crashed last week start its journey from? An "eastern bypass" from Murray Bridge to Gepps Cross won't divert all the traffic that originates in the Adelaide Hills or whose destination is in the suburbs south of the CBD.

Moving the Cross Road stop line back 100m sounds good until anyone starts to think about how much longer the light at the bottom of the freeway would need to be red to enable people to drive, ride, or walk from way back there to cross Glen Osmond Road.

The idea of using the managed motorway equipment to clear the queue from in front is good. That might encourage unstoppable vehicles to continue on to Glen Osmond Road without attempting to turn, but I'm not sure how often that will be a sufficient solution, rather than just shift the problem down to Fullarton Road. The reality is that thousands of trucks descend the hill without crashing and there are tens of other black spots or stretches of road across the state that are equally dangerous, just not as high profile when things go wrong.

[abc]

Why not just install a concrete barrier in the median strip of Cross Rd?

Sure, this wouldn't stop traffic heading west on Cross Rd from being hit by an out of control truck, but neither would moving the stop line for the intersection further east.

There's probably not enough concrete in all of South Australia to build a wall thick and tall enough to stop a runaway truck.


IMO, as a truck driver who descends the freeway once or twice a month, there's nothing that can be done to fix the problem with the intersection in its current configuration.

An arrestor bed wouldn't have saved that last truck from rolling.. He just took the left turn way too fast, could have happened at any other intersection.

I see more smoking brakes going down Grand Junction road towards the Gepps Cross intersection than going down the freeway

The existing median is about 2m wide.

A 2m wide, 1m tall barrier would surely be as truck proof as you can get. Obviously wouldn't be great for the poor driver of anything that hit it though.

I guess this just leads to the discussion thats happened countless times in the past. What's the long term plan for the intersection and the freight route from Murray Bridge to Adelaide?

what you're suggesting is ludicrous

what would work is build a lake behind the gateway fountain about 5ft deep

[SBD]

Most public discourse of the "problem" seeks to introduce engineered "solutions" that rely on a panicked driver (who has likely already made at least one mistake) suddenly choosing to do something that is dangerous to themselves in the hopes of not injuring some hypothetical other people.

I doubt any driver would at that moment choose to plough head-on into what they believe is an unmoveable concrete block. Some of them might choose to drive into a lake, but a smooth entrance to a lake only five feet deep in that area looks difficult, too. Straight on then a gravel bed where the road levels out is far more likely to be an accepted option, if the traffic management can provide a smooth clear path, then big steel barriers forcing the only remaining vehicle into the gravel, like it or not.

[Nort]

Clearly what is needed is a grid of several hundred high speed raise bollards laid out across the intersection.

Usually down, they will be under the control of an AI monitoring system which on detecting an out of control truck will raise the necessary bollards to bring the runaway vehicle to a stop. Extra bollards will then raise higher underneath the wreckage to lift it up and create a path underneath through which the other traffic can travel.

Should this be seen as impractical, there is an alternate suggestion that involves a series of trapdoors at the bottom of the freeway, that can be similarly triggered to drop the truck into a pillowed safety pit.

[abc]

at least my solution gives the truck driver an option to live

[SBD]

at least my solution gives the truck driver an option to live

Nort's solution has the potential to slow down a truck gradually enough to save the driver if "engineered" means they bend/resist a certain amount of force then yield to the next one so the truck doesn't stop in the length of the front bumper.

The challenge is to work out what kind of truck is likely to be "next". A fully-laden B-double might require different handling than a mobile concrete pump or sewage truck. I don't know how often cars arrive at the intersection with imperfect brakes. We wouldn't hear if they just use the truck in front or a couple of cars as a buffer.

[Eurostar]

After how much money has been fixing the South Eastern Freeway , whereas how much of that money could be put in to upgrading road between Murray Bridge and Truro or a southern bypass (the B34) the descent of Willunga Hill (Victor Harbor Road) wouldn't be perfect but at least a runaway truck would crash into say a vineyard vs the Cross Road junction.

[SBD]

After how much money has been fixing the South Eastern Freeway , whereas how much of that money could be put in to upgrading road between Murray Bridge and Truro or a southern bypass (the B34) the descent of Willunga Hill (Victor Harbor Road) wouldn't be perfect but at least a runaway truck would crash into say a vineyard vs the Cross Road junction.

A Murray Bridge detour only "solves the problem" for traffic coming from the Southeast and Victoria, not traffic from the Adelaide Hills (where did the most recent vehicle come from and intend to go to?).

Thousands of trucks successfully travel down the freeway through that intersection every day. There have been two fatal crashes on the Swanport Bridge in the last ten years or so too. Would duplicating the bridge also be an effective way to spend the money? The bridge now seems to be narrower than the one-way carriageway approaching it from either side.

I'm not convinced that any engineering solution can "fix" the freeway to completely prevent rare incidents. There have been at least two morning peak hour issues on the divided carriageways since that crash. The Transport Minister was on the radio talking about configuring it for contraflow - presumably one lane in each direction on the outbound carriageway from Mount Barker to Bridgewater for the recent delay, which was cleared well before midday. These seem like large amounts of money to compensate for a small number of incompetent drivers.