30 April 2018

Wire Rope Safety Barriers from CSP – the right barrier for the road

Flexible wire rope road safety barrier systems, also known as wire rope barriers (WRB), are being increasingly specified in median and side of road installations across the country by the NZ Transport Agency and Councils as evidence continues to prove that WRB systems are far more forgiving on the human body in both car and motorcyclist incidents than any other type of barrier. WRB systems are specifically designed to redirect the vehicle gently, thereby significantly reducing the impact on the occupants of vehicles.

Flexible safety barriers are designed to prevent traffic leaving the road or crossing the centre line and colliding with hazards such as other vehicles, trees and poles. They 'catch' and then redirect vehicles so a vehicle impacts the wire rope safety barrier the cables flex, slowing the vehicle and pushing it back into its lane with the system absorbing the impact. This creates a more forgiving road that can help avoid mistakes becoming fatal.
Flexible road safety barriers are narrow and work best on long, straight sections and gentle curves. More importantly though, the NZ Transport Agency says that, when fitted along the centre or the side of the road, they reduce the number of people killed by 90%.

WRB and the motorcycle

There is solid evidence to disprove that wire rope barriers have a ‘cheese cutter’ effect and are an increased risk for motorcyclists. In fact the evidence shows the opposite. Installing roadside and median barriers – particularly wire rope barriers – reduces the likelihood of motorcycle casualties by up to half. This is because motorcyclists are more likely to survive an impact with a roadside or median wire rope barrier than an impact with a tree, pole or oncoming vehicle.

CSP’s two WRB options suit all types of New Zealand’s roads:

Armorwire Wire Rope Barrier – safety with good looks

Marine Parade’s iconic row of Norfolk pines in Napier were first planted in the 1890’s and have been the subject of controversy over the years - not because of their size, but because they have become a safety hazard for motorists.

The southern end of Marine Parade has a 100km speed zone and has, over the past 30 years, been the location of 15 fatalities and many more serious injuries from impacts with the trees. CSP’s Armorwire Safety Barrier was chosen for the picturesque spot for its safety record and because it was the least visually intrusive of the various wire rope barrier systems available.

Armorwire Wire Rope Barrier:

  • Tested to NCHRP 350 TL-3 and TL-4
  • Exceptionally good vehicle control and behaviour
  • Can be used in either edge of road or median application
  • Easily installed and low maintenance
  • Small number of components in system make up
  • Easily repaired after impact
  • Designed and manufactured in New Zealand
  • Low cost patented technology

CSP’s Brifen WRB – put to the test on Brynderwyns

Over the years Brynderwyn Hill on State Highway 1 north of Auckland has been a notorious hot spot for motor vehicle crashes. In late 2014 the NZ Transport Agency contracted United Civil Construction, as part of the Safe System project, to widen the road, remove tight corners and install 14kms of wire rope barrier using CSP’s Brifen WRB system – to separate north and south bound traffic from the top to the bottom of the hill.

CSP’s Brifen Wire Rope system was chosen over others due to its interwoven cable system which is best suited to curved installations. When the barrier is impacted the interwoven cable system ensures the tension is kept on the cables at all times, even on tight radii.

Brifen Wire Rope Barrier:

  1. Tested and approved to NCHRP 350 TL-3 and TL-4
  2. Tried and tested good vehicle control and behaviour
  3. Can be used in either edge of road or median application
  4. Easily installed and repaired with low maintenance cost
  5. Can be used on tight curves without reducing the post spacing
  6. Aesthetically pleasing appearance