A vehicle should not be torn apart like this after striking a roadside barrier that should be designed to reduce the severity of a collision.
On the morning of Monday, July 23, 2018, the Ontario Provincial Police (OPP) reported on their Twitter account that a collision occurred on Highway 401 near the Highbury Ave exit at London, Ontario. No other information was made available nor did any official news organization report any further details of the crash. Gorski Consulting examined the site of the crash on July 27th, with some disturbing results.
A vehicle had been eastbound on Highway 401 and as it approached the exit ramp toward Highbury Ave. It veered off the pavement and headed toward the south guardrail. The end of the guardrail was equipped with an ET-PLUS terminal that was manufactured by Trinity Highway Products of Dallas, Texas. Anyone who has been following the status of roadside collisions in recent years would have heard about the controversy surrounding the ET-PLUS terminal as there was a well-publicized civil trial that took place claiming that the terminal was detective. While the U.S. Federal Highway Administration failed to confirm that the terminal was any worse that other systems the manner in which that conclusion was drawn was suspect. Regardless, the ET-PLUS terminal has received a record of questionable performance.
Gorski Consulting has been monitoring the performance of ET-PLUS terminals since becoming aware of the controversy in 2014. Since then an increasing number of installations have been examined and the results of impacts have been documented. Questionable results have been found yet there has been no official response from agencies such as the Ontario Ministry of Transportation which continues to allow the terminals to exist on Ontario’s highways. While the ET-PLUS used to be the primary and most popular terminal installed in Ontario, there has been a quiet replacement of those installations toward other manufacturers without further explanation.
The most recent impact of the ET-PLUS terminal on Highway 401 at Highbury Ave exemplifies the concerns about the performance of the terminal. The photo below shows the status of the impacted terminal when it was inspected on July 27, or about 4 days after the actual collision.
View, looking east, along the south roadside of Highway 401 at the aftermath of destruction visible after an eastbound vehicle struck the ET-Plus terminal in the background.
Upon first approach to the struck terminal it appeared to be missing from the end of the guardrail, as shown in the photo below.
Upon first viewing, the impacted ET-PLUS terminal seemed to be missing from the end of the guardrail – until one looked a little closer.
The photo below shows a view of the ET-PLUS in October, 2014 when it was first surveyed as part of a research study.
This is a view of the ET-PLUS terminal from October, 2014 when Gorski Consulting surveyed its condition as part of a research study.
Upon closer inspection it was revealed that the back portion of the ET-PLUS terminal, the channel, was still present and attached to the guardrail. However the frontal plate was missing, as shown in the photo below.
Closer inspection showed that the back “channel” of the terminal was still attached to the guardrail but the front plate appeared to have ben torn off and was missing.
A close-up view of the location where the channel was welded onto the plate showed that there had been a separation. This is a rare occurrence based on the select impacts that have been observed to date. The photo below shows a close-up view of the area of the separation in the weld of the terminal.
The peculiar circumstance is that the frontal plate of the terminal seemed to broken away at its weld with the channel.
Looking at the remainder of the guardrail there was evidence that it had buckled and therefore some energy was dissipated, as shown in the photo below.
The buckled remains of the guardrail indicated that some energy was dissipated from its deformation but this is not the way that the system should perform.
But that is not the way the system was designed to perform. As shown in a controlled test in the photo below, the head (plate) and channel of the terminal is supposed to be pushed along the guardrail like a locomotive riding a railway track. In doing so, the rail is supposed to pass through a narrowing in the terminal (“the throat”) which causes the guardrail to become deformed, like a ribbon. This process of squeezing through the throat and deforming the guardrail is the mechanism by which energy is dissipated in a controlled manner.
As shown in this frame from a high speed test conducted by the South-West Research Institute in Texas, the ET-PLUS terminal is designed so that the guardrail passes through the throat of the terminal causing the rail to become “ribboned” and this passage is what creates the required dissipation of energy.
Looking east along the side of the highway from where the impact occurred there were numerous parts of the vehicle which disintegrated, as shown in the photo below.
Looking east along the side of the highway there was evidence of many pieces of the striking vehicle which disintegrated after the barrier impact.
Some of the major components of the separated vehicle that were found strewn along the roadside was the front bumper reinforcement bar. This is the metal part of the bumper that is behind the plastic exterior. A cord was attached from one end of the bar to the other to demonstrate the extent of crush of the unit, which should normally be straight.
The reinforcement bar of the front bumper of the striking vehicle had an obvious crush in it which matched the width of the front plate of the ET-PLUS terminal.
Measuring the crush of the bar with a tape measure showed that the crush was about 46 centimeters, as shown in the photo below. Measurements like these can be used to estimate the extent of energy that was dissipated while also providing an estimate of the collision severity in terms of its change in velocity (Delta-V). Those calculations can be difficult when a vehicle disintegrates.
A measurement tape was used to measure the extent of crush of the front bumper reinforcement bar.
The width of the notch in the reinforcement bar was also revealing. As shown in the photo below, the maximum penetration was over a width of 40 centimeters.
The width of the maximum penetration of the bumper re-enforcement bar was 40 centimetres and this matches the width of a typical plate of the ET-PLUS terminal.
As confirmation, the photo below shows a measurement being taken of the plate of a typical ET-PLUS terminal. The width of 40 centimetres is the same as the width of the maximum crush in the re-enforcement bar.
Example of the measurement of the width of a typical plate of the ET-PLUS terminal or 40 centimetres.
So, even without having the opportunity to examine the vehicle, we can say that it was likely not sliding sideways, or not even in a substantial yaw, when it struck the terminal.
Another part of the vehicle that was found on the roadside was the vehicle’s engine, as shown below.
View of the engine of the striking vehicle which had become separated after the vehicle disintegrated.
Close to the location where the engine was resting the separated transmission was also nearby as shown in the photo below.
View of the vehicle’s transmission lying, separated, near the separated engine. Walking further eastward the vehicle’s windshield was found, as shown in the photo below.
Walking further eastward the vehicle’s separated windshield was found.
Walking further to the east an area of fractured red lens material was found. This is where the remaining portion of the vehicle tumbled and one of the rear corners of the vehicle made ground contact before coming to rest.
Walking further eastward an area of fractured red lens material identified the location where one of the rear corners of the vehicle made ground contact before coming to rest.
Walking still further eastward an area of trampled grass was located where the remaining portion of the disintegrated vehicle had come to rest, as shown in the photo below.
View, looking west, of the area of trampled grass which typically identifies the final rest position of a vehicle. The initial impact of the terminal can be seen in the distant background.
Some measurements were taken to establish where the various portions of the vehicle had come to rest. Using the original position of the ET-PLUS as a zero point, the front bumper came to rest 39.0 metres to the east, the engine came to rest 53 metres and the remaining portion of the vehicle came to rest at 69 metres east of the original location of the terminal. Assuming a rather moderate deceleration level of 0.5g, the vehicle’s rest position at 69 metres would indicate that the vehicle left the area of impact, at a speed of about 94 km/h. That speed is after the deceleration caused from damaging the barrier and causing the crush to its front end. Clearly this was a high speed impact yet it is an impact speed that is tested for safety compliance of the barrier system.
The curiosity of this incident is the lack of any official, public reporting of its consequences. It is possible that, through some miraculous circumstance, the driver, or perhaps additional occupants survived this massive collision without major injury. But that seems rather doubtful. So why was it not reported to the public?
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