Traveling down the road nowadays it has become perfectly common
to spot different kinds of road crash barriers. They are used in every country
as a safety measure that will prevent people from facing accidents and other
mishappenings. Everybody knows that the roadside hazards can be a very serious threat, but many consider some
barriers as unnecessary obstacles along the way. Especially when they’re placed
in the middle of the road. On the other hand, every government claims that
they’re an essential part of every road construction project since they ensure
safe transportation for all drivers, mainly in the form of absorption of the
force of impact. Either way, it is important for every road user to identify
road crash barriers, so let’s take a look at the types.
From Jersey With Love
Let us
first take a look at the origin. They all share the common name of jersey
barriers, but have you ever wondered why? Because these seemingly simple
partitions that divide the traffic are actually quite sophisticated and
shouldn’t be taken for granted – in order to ensure perfect safety in the event
of a crash, their designs have been well-tested and adapted since they were
first used in California in 1946 to replace the weak wood beam guardrails on
Ridge Route Highway. This route was the first Dead Man’s Curve with the 6-percent
downgrade of the road that produced many head-on collisions. Then the state of
New Jersey adopted similar concrete structures in the similarly hazardous
section of US Route 22 in Hunterdon County. Although these initial barriers
reduced the impact of collisions quite successfully, the highway engineers of
New Jersy continued to tinker with their design following the observation of
the number of accidents and created progressively larger prototypes. And thus
the standard barrier was created in 1959 that would bear the name of the state
where it was developed although its implementation would become global and its
design would achieve the variety before us.
Impact Resistance
One
thing that divides road crash barrier types is the way they deal with the force
of impact.
- Flexible
These
flexible systems are made with wire rope and their design makes the
vehicle smoothly redirect after the car crash, minimizing the severity of the
impact. They consist of wires and frangible posts in between so they are able
to divert any type of vehicle. But the impact itself creates the damage to
these barriers and they need to be repaired afterward.
- Rigid
These
rigid systems are structures of reinforced concrete and the vehicles
that have lost control will be contained and redirected. Upon hitting the
barrier the vehicle will only experience the small impact, which makes these
types of barriers most suitable for places on the road where the impact angles
are low. The maintenance is low and the heavy vehicles will experience the highest
protection.
- Semi-Rigid
These
semi-rigid systems consist of steel beams and rails, so they don’t deflect as
much as the flexible ones, but upon the point of impact, they become deformed
completely. Usually, they are installed very close to hazards and there are a
lot of types, most common ones being the Thrie-Beam steel system and the
W-Beam steel barrier Type 4.
The Location
The
other thing that divides road crash barrier types is the location they are
placed on.
- Roadside
From
steep slopes that cause rollover crashes and fixed objects such as bridge piers
to bodies of water, the purpose of these roadside barriers it to defend the
traffic from roadside hazards or obstacles. They can be also used with medians to prevent vehicles from the
collision with hazards within the median.
- Median
The
purpose of these is to prevent the vehicles from hitting oncoming ones in a
head-crash by crossing over a median. For this reason, their design needs to
allow them to be smacked from either side.
- Bridge
The
plan behind these bridge barriers is to hold down the vehicle from crashing off
the side of a bridge and to prevent its fall into the river, onto the railways,
or the roadway below. In order to prevent buses and trucks, but also cyclists
and pedestrians from rolling or vaulting over the barrier where they could fall
over the side of the arrangement, they are generally built higher than roadside barriers.
- Work Zone
Their
sole purpose is to be guardians of traffic against hazards in work zones. This
makes them possess a distinguishing trait of the ability to be moved due to the
shifting conditions in the roadworks. The two most common types are the water-filled barrier and a temporary
concrete barrier. The second is more preferred because the first can’t be used
in cold weather – it is composed of steel-reinforced plastic boxes which are
linked together in order to form a longitudinal barrier where it is required,
and in the end, ballasted with water. Nevertheless, they don’t require heavy
lifting equipment to be collected, which is certainly a benefit.
Now you
know where and you know why. They are obstacles, but they’re positioned for a
good reason
