THE ROLE OF ASPHALT IN ROAD SAFETY
We all know that the surface condition of the road affects the accident rate: exudations, pits and rutting increase stopping distances and promote abrupt maneuvers, especially in wet conditions. At Grupo Bitafal we are working on techniques and products to reverse this problem.
As Voltaire said, “There is no such thing as an accident. What we call this name is the effect of some cause that we do not see ”. In general, the incidence of the human factor is the main cause of claims, although the causes are really multiple and some are not very controllable. However, from our perspective and our commitment to Road Safety, the surface condition of the road is a controllable factor and we are working on various techniques and products that substantially improve this situation.
Traffic accidents are one of the most deadly evils in our country. From January 1 to November 30, 2020, a total of 19,721 people were injured by traffic accidents, of whom 347 died and 2606 were seriously injured, according to official figures from UNASEV. Although the rate decreased compared to the previous year (figures strongly influenced by the voluntary mobility restrictions of the pandemic), they continue to represent a problem to which we must pay careful attention.
We detail below some of the main causes and possible solutions:
Hydroplaning and “Spray” effect:
For example, if the asphalt does not drain the water well or due to defects in the road an accumulation occurs, the famous problem of aquaplanning or hydroplaning occurs. At the same time, in closed mixtures, the “Spray” effect occurs on rainy days that make visibility difficult. Beyond the profile of the road that must ensure drainage as well as have a low rut to avoid accumulation, there are solutions that are capable of improving this drainage.
One of the solutions that has been applied experimentally in Uruguay is an F10 mixture with modified asphalt BITAFLEX AM3 in which a higher macrotexture (above 1.0 mm in the sand patch) was achieved than in usual semi-dense mixtures and allows to reduce the "Spray" effect mainly. Even so, it is necessary to see alternatives that drain more water, so we are working to carry out a overcoated with a drainage-type mix with modified asphalt BITAFLEX AM3, asphalt rubber AMC 50 the highly modified asphalt HiMA. The high viscosity of these binders allows the mixture to be applied while maintaining its high percentage of voids and its excellent performance against permanent deformation, preventing the formation of rutting and water accumulation as well as eliminating the “Spray” effect.
The greater the voids on the surface, the safer the rolling, so there are alternatives with surface treatments that allow improving sections that have these problems. For example we have applied in Uruguay type surface treatments “Chipping" O cold microagglomerates to solve the rutting problem in such a way as to restore the transversal profile of the road and allow the normal drainage of water towards the sides. On the other hand the application of multiple locked treatments (TMT) It allows to generate voids but with a more comfortable and less noisy rolling.
Lack of texture and friction:
A problem related to the previous one but which is approached in a different way is the issue of the lack of friction of the road due to exudations or loss of texture of the stone aggregates. This can normally occur in heavily requested areas such as intersections, traffic lights, access to roundabouts, roundabouts, etc. In these cases, loss of vehicle control, increased stopping distance and skidding can cause serious accidents. To improve friction we are also working with high friction Seal Coat treatments, composed of high performance binders and excellent resistance aggregates. These treatments have the additional possibility of generating a red, blue or green color surface, which improves the visibility of the road and the driver's attention.
Wells:
Finally, the problem with wells is that they usually generate abrupt maneuvers at high speeds that can end in a collision or loss of control of the vehicle. For this, at Grupo Bitafal we work to promote preventive treatment, with the use of a battery of surface treatment techniques that allow, with the same money as with a milling and replacement scheme, to maintain a high standard of the pavement, ensuring the absence of wells.
In secondary and urban roads we have been working with departmental municipalities for several years supplying the family of emulsions MIX 55 to make cold mixes for patching.
In short, these are the latest developments in materials and techniques that improve road safety. We want to invite anyone interested to see our facilities and see these innovations first-hand.
