I was thinking they should be connected with a steel cable at the bottom, and a hook inside the plastic shell, so if a car hits them, they grab on and start slowing the car down.
No. Each post should be solid enough to stop, or significantly slow a car on its own. They need to be built to protect vulnerable road users from cars. Slowing the cars gradually does not do that.
Cables under tension can snap back which makes your idea even more dangerous than just a concrete block.
Eh, there are genuine situations where you don’t want to stop the vehicle immediately, like say if this trucker came up on the other side and pushed the filming car into the bike line. Having a controlled line that brings the vehicle to a stop is much safer than having concrete and steel barriers that just shred the car and the occupants. Similar cable systems are already installed to stop cars, so the engineering has been done to prevent those dangerous snap-backs.
Those systems are designed to dissipate the forces by crumpling and creating debris that is thrown away from the middle of the road. The crash panels at the start of cable systems and guardrails are designed to launch debris in a colission. Incredibly dangerous for cyclists or pedestrians, which is why they are installed at road edges. They are completely unsuitable to be barriers between different types of traffic.
Highway medians are almost always concrete walls. There is a reason those cable systems are not used between lanes of traffic.
I’m referring to urban highways where opposing lanes are right next to each other, like the sort of spacing that you would need for a barrier next to a bicycle lane. Those cable systems are only installed in cases where there is generous clearance for debris, which is not applicable for the roadside bicycle lanes we are discussing.
Admittedly it would be much safer for those in the bike lane if we dug a W profile ditch in pace of the car lanes. For some reason I don’t see that happening.
I was thinking they should be connected with a steel cable at the bottom, and a hook inside the plastic shell, so if a car hits them, they grab on and start slowing the car down.
No. Each post should be solid enough to stop, or significantly slow a car on its own. They need to be built to protect vulnerable road users from cars. Slowing the cars gradually does not do that.
Cables under tension can snap back which makes your idea even more dangerous than just a concrete block.
That’s how they are in Europe. Slam into one of those and you basically have to get a new car.
You need to promote it as “anti-terrorist hardening to protect cars from terrorist ramming attacks”. It’s more likely to get support.
If that’s what it takes.
Eh, there are genuine situations where you don’t want to stop the vehicle immediately, like say if this trucker came up on the other side and pushed the filming car into the bike line. Having a controlled line that brings the vehicle to a stop is much safer than having concrete and steel barriers that just shred the car and the occupants. Similar cable systems are already installed to stop cars, so the engineering has been done to prevent those dangerous snap-backs.
Those systems are designed to dissipate the forces by crumpling and creating debris that is thrown away from the middle of the road. The crash panels at the start of cable systems and guardrails are designed to launch debris in a colission. Incredibly dangerous for cyclists or pedestrians, which is why they are installed at road edges. They are completely unsuitable to be barriers between different types of traffic.
Highway medians are almost always concrete walls. There is a reason those cable systems are not used between lanes of traffic.
Funny you mention this, because most highway medians are a W profile ditch, or a cable catch system (which is similar to what I described).
I’m referring to urban highways where opposing lanes are right next to each other, like the sort of spacing that you would need for a barrier next to a bicycle lane. Those cable systems are only installed in cases where there is generous clearance for debris, which is not applicable for the roadside bicycle lanes we are discussing.
Admittedly it would be much safer for those in the bike lane if we dug a W profile ditch in pace of the car lanes. For some reason I don’t see that happening.
https://youtu.be/jyNEnYaBszk
Those cable systems already exist, just not in the US.