Many years ago, all guard rails had flat blunt ends and when a car ran off the road and struck them, they sometimes pierced the car like a lance. To remedy that, engineers redesigned the guard rail and we started seeing guard rails that smoothly disappeared into the dirt at the ends, eliminating the killer blunt ends. Now I'm seeing blunt ends again, this time with some sort of spring energy-dissipator and yellow striped refelective surfaces. But that spring isn't going to help much when a car is going 60 miles an hour (or 80). Why did the smooth "disappear into the ground" type of guardrail get replaced? Aren't we going back in time here, with an increase in danger to the driving public?
2007-02-24 12:56:06 · 7 answers · asked by Daniel C 1 in Cars & Transportation ➔ Safety
thats the new style guardrail that when you hit it, it will slow you down and the guardrail folds like an accordian and the legs break away.
2007-02-24 13:02:53 · answer #1 · answered by mister ss 7 · 1⤊ 0⤋
The guard rails that tapered into the ground had a tendency to act as a ramp. A car would run up on it and flip, causing greater injury and more accidents by leaving the car totally out of control. The new type of rail ends collapse on direct impact, (imagine a multi-segment telescope). The end cap of the rail moves forward with the impact of the vehicle, the rail itself comes out the top and sort of curls. The first dozen or so of the stakes that hold the rails to the ground are made from wood so they'll break off.
2007-02-24 22:54:35 · answer #2 · answered by mmrvl 1 · 0⤊ 0⤋
The guard rails that ended in the ground were causing cars to lift off the ground when impacted at the ends .Resulting in many fatalities and destroyed cars .
As for the energy dissipation the ends are curled to lessen the impact so as to reduce the piercing force .And they have a cable installed from end to end to take up additional impact force energy across the entire guard rail in itself .
This reduces the force of the collision energy very quickly resulting in less damage spreading it across the entire rail and less to the car .
2007-02-24 21:12:58 · answer #3 · answered by dinosaur 4 · 0⤊ 0⤋
I think mister ss is correct.
It could also be that the other guard rail design that bent down toward the ground had the potential to flip a car over if the car ran up and over the rail. Kind of like a ramp.
I've got no hard data on that theory but I have seen it happen.
Props to will also for his answer!
2007-02-24 21:11:58 · answer #4 · answered by Mr. Badwrench 6 · 0⤊ 0⤋
they my have made them weaker to act as a crumple zone instead of a lance. one prob with the into the ground version is the fact that its a ramp and could flip the car into more traffic. the idea with new ones is its strong enough to resist the car and stop the car going through it but weak enough that the car doesn't just bounce out back into more traffic.
2007-02-24 21:06:45 · answer #5 · answered by will 2 · 1⤊ 0⤋
Probably some lawyer did and made millions on a class action suite.
2007-02-24 21:05:31 · answer #6 · answered by Anonymous · 0⤊ 0⤋
no danger to the public...if you hit one and drive that bad...you need your car totalled and get off of the road...honest answer ....have a good evening
2007-02-24 21:02:59 · answer #7 · answered by Michael K 5 · 0⤊ 0⤋