NRA Responds To Concerns About Road Surface Quality
24th January, 2002
NRA RESPONDS TO CONCERNS ABOUT ROAD SURFACE QUALITY
Reports suggesting a safety hazard to drivers as a result of a new process in road construction and maintenance were dispelled today (Thursday 24th Jan 2002) by the National Roads Authority.
Modified Stone Mastic Asphalt (SMA) was initially developed in Germany and subsequently used in other countries including the UK.
As part of the ongoing programme of research and development the NRA - exploring the potential of new materials to improve road construction and maintenance performance as well as road safety and cost efficiency - introduced the process on 1% of the roads network.
SMA has only been used in Ireland in the last two years.
However, close monitoring has indicated the possibility of a faster deterioration of surface texture than traditional materials.
Local Authorities have been instructed by the NRA to confine usage of the new process to 30 m.p.h. zones as a positive safety measure.
The NRA's rigorous performance requirements ensure that No Hazard is presented for drivers at any location where SMA has been introduced.
Wear and tear of road surfaces with declining skid resistance is a normal feature of the life cycle of all roads. The Authority's experience with modified Stone Mastic Asphalt indicates the possibility of a faster loss of surface textures than is the case with the traditional road surface material, Hot Rolled Asphalt, which could have implications for the future skid resistance performance of the roads concerned.
The possible shorter operational life of modified Stone Mastic Asphalt, if not rectified in further development and testing of the material, would have road maintenance cost implications. The Authority has accordingly decided that further use of the material should be restricted until product development establishes that surface texture performance over an acceptable life cycle can be guaranteed.
The NRA on an on-going basis monitors the skid resistance of road surfaces. The monitoring programme provides coverage of the entire national primary network on an annual basis and the national secondary network over a two-year cycle. These results, together with supplementary results of the performance of modified Stone Mastic Asphalt are used by the Authority to identify locations in the network, which require attention as part of the annual road maintenance programme.
Road grant allocations are targeted by the Authority at locations where road surfacing is warranted taking account of skid resistance/ the potential of the road concerned to fall below the standard of the performance required for the national road network.
For further information please contact
Caroline O'Brien
01 6602511 Ext. 254
086 6049430
or
Richard Evers
01 6602511 Ext. 234
086 6062950