Do we need fatal consequences before the public is informed of a potential safety problem? Given the lack of reporting of a truck recently crashing through a Highway 401 barrier it would appear so.
This photo shows the median barrier located just west of Mill Road on Highway 401, approximately 15 kilometres south-west of London, Ontario, where an eastbound truck crashed through the barrier sometime before the afternoon of February 28, 2019.
There was no coverage of the incident by official news media other than information from police informing that the westbound lanes of Highway 401 would be closed west of Colonel Talbot Road (Highway 4) to remove a truck out the median. There was no indication when the incident occurred nor were there any photo images of the truck or how it managed to break through the barrier.
The character of the barrier where this breakage occurred appeared to be some form of a “Temporary Concrete Barrier” (TCB). These barriers are used in construction zones often to separate workers and to protect them traffic during road construction. The Ontario Traffic Manual, Book 7, Temporary Conditions describes such barriers as “…commonly used in section lengths of 2.5 to 4.0 m, connected together to form a continuous barrier”. Judging by the length of the slabs shown in the above photo they were likely 4 metres long.
Even if no injuries occurred the fact that there was a penetration through the barrier should be highlighted. These TCBs are used throughout North America and any failure could affect the safety of construction workers, occupants a the striking vehicle and other persons driving in vehicles in the immediate vicinity of the impact.
The strength of any barrier is related to its length. In order to displace the segment thus sustains direct contact, tension is increased along the segments making that displacement progressively more difficult. However, when there is a separation in the barrier that tension is released. It is only the mass of the individual segments that become the obstructions to a striking vehicle’s post-impact motion. As can be seen from the above photo it is clear that the barrier segments separated thus weakening the barrier and resulting in the inappropriate displacement of the separated pieces.
In the photo below it can be seen at the area of displacement of the concrete segments was very local, involving perhaps only four or five segments. The remaining segments remained in their original position. This indicates that the energy was not dissipated along the longer length of the barrier but only by the four or five segments that were directly impacted. Such an outcome is not desirable. In the photo below one can see only of the concrete segments was actually thrown across the median and is resting near the wall of the concrete barrier for westbound traffic.
Separation of the barrier segments meant that they became displaced further from the original position and, if workers had been present, would likely cause significant injury or death to any standing nearby.
The photo below shows a clearer view of the one concrete segment that is lying on its side with its base facing the camera.
View of one of the concrete segments of the barrier that was thrown across the median.
A close-up view is needed of the wall of the struck barrier to determine how and why the separation occurred. The photo below shows a closer view of the struck side of the barrier but nothing of substance can determined without taking a much closer look.
A close examination need to be made of the struck wall of the barrier and its anchorages to see how and why the separation occurred.
Overall, there needs to be greater attention paid to these median impacts and their consequences. Gorski Consulting has mentioned in previous news items on this website that there is a lack of proper reporting of these median impacts and their consequences along Highway 401. At present there is a High Tension Median Barrier being installed in the area of the present impact. Many citizens in the area have concerns about whether such a cable barrier provides sufficient protection from median crossings by heavy trucks. The preference of some in to install a Jersey-type, concrete barrier that is believed to be more capable of redirecting large and heavy trucks. Data on the the real-life performance of a Temporary Concrete Barrier with impact by a heavy truck might provide some education into the discussion. Thus all incidents of impact with the median barrier need to be properly and publicly identified.
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