POTHOLES? GPR, MODIFIED BITUMENS AND ROAD PATCHERS
New technology to solve a long-standing (and dangerous) issue
A widespread use of modified bitumen can translate into a longer road lifespan as well as greater safety for road users
Potholes that suddenly appear in front of our cars, cracks, depressions and upheavals just to mention a few, and all of them not exactly good for our tires. This is unfortunately the harsh reality facing anyone driving on Italian roads, whether in or outside the cities. It takes a lot more than just fitting off-road tires!
Local authorities try to repair the roads when and how they possibly can, often with the usual "patches" which literally disappear overnight prompting volunteers into action, fixing potholes at their own expense. Things can no longer go on like this!
Going under the surface
The solutions are there, cutting-edge technologies and tools such as ground penetrating radars, infrared thermography, deflectometers, profilers and laser scanners that can not only scan the asphalt surface, but also "see" what's under it and then scientifically study the causes of road deterioration and how they develop, without extensive (and expensive) interventions.
All that is needed is to travel over a section of the road with a suitably equipped vehicle, able to "map" every square millimeter of the road in no time, at a speed of 70-100 km/h – without hindering the traffic flow - gathering a large amount of information which must be then analyzed by experts who will have to come up with real solutions to long standing problems.
Polymer modified bitumen
Nevertheless, once a correct analysis of the situation has been performed, there is a need to intervene using advanced materials such as, for example, polymer modified bitumen, traditional bitumen modified with the addition of special polymers that provide a variety of characteristics depending on the applications. But what is a polymer modified bitumen?
In general, we can say that, compared to traditional bitumen, the modified product is more resistant to load, wear and tear and is able to better cope with variations in temperature, has a longer lifespan and a greater resistance to deformations, cracks, potholes and so on. Of course, polymer modified bitumen is more expensive compared to traditional products, but the end results in terms of performance offered and durability are far superior.
It is no coincidence that the main users of this technology are mainly private entities who take into account not only the initial financial commitment, but also all the following costs for necessary repair work. This is the case of motorway concessionaires and airport companies such as the Fiumicino Airport, race tracks like Vallelunga and Misano, as well as a multinational company like Bridgestone that chose Total-Erg polymer modified bitumen for its European Proving Ground in Aprilia, providing excellent performance with important advantages in terms of elasticity and durability.
A widespread use of modified bitumen can translate into a longer road lifespan as well as greater safety for road users. For example, just think of the draining tarmac technology considered by many as an important technical innovation at international level. A Dutch study has shown in this regard that the characteristics of wet draining asphalt are comparable to those of dry asphalt, and by paving with it, motorways and main roads could reduce by as much as 25% the number of deaths and injuries due to accidents with a containment of costs that would cover the high initial investment costs.
In general, if we take only figures into account, we can say that, if bitumen accounts for about 30% of the total costs, an extra 20%, on average, must be added for modified bitumen. Despite its initial financial burden though, the far longer working lifetime - up to three times longer than traditional bitumen – can turn into a considerable saving due to a reduced need for maintenance, less environmental damage, less wastage of financial resources and greater safety.
Once the best materials have been chosen, the most appropriate tools must then be used. Cutting edge technology and machinery, tested and used for over twenty years in other European countries, provide the best lasting solutions. Road patchers are an excellent example of this, providing a superior repair method using hot and cold mixes, thus saving time and money.
The method is rather simple, the machine performs 4 operations in a short time: the hole is blown clean of foreign objects, such as leaves and pieces of wood; tack coating of the edges as well as the bottom of the hole with special emulsions based on modified bitumen; a mixture of aggregate material is then blown into the hole at high speed; finishing and compacting. Imported and distributed in Italy by Combicons, the "Road Patcher" allows to obtain a smooth and uniform asphalt guaranteed for two years. With further advantages for motorists such as maintenance procedures performed in a few minutes allowing traffic circulation to resume immediately without any damage to the work done.
Four simple stages
1 – Cleaning. A jet of compressed air removes from the hole all the sediment within it in order to optimize the adhesion of the emulsion.
2 – Tack coating. Tack coating of the edges with bitumen emulsion. If the bottom of the hole consists of old surfacing, this is also tack-coated.
3 – Filling. A mixture of aggregate material is then blown into the hole at high speed, which provides higher durability than any other method, until the hole is completely filled.
4 – Sealing and compacting. Tack coating/sealing with bitumen. Covering with a thin layer of aggregate material prevents lifting of the repair material by the traffic. Finally, the aggregate is compacted to give it a smooth finish.
Gianni Serra, Head of bitumen at TotalErg
"Our products are manufactured in specialized facilities through an eco-friendly process," says Gianni Serra, head of bitumen at TotalErg. "Our experience allows us to produce high performance emulsions guaranteeing TotalErg a leading position in Italy in the high-tech modified bitumen market thanks also to the contribution of our international research and testing centers. We hope that local governments will seize our proposal as an opportunity to improve the condition of our roads and guarantee a higher safety to those who travel on them each day".
TotalErg modified bitumens
TotalErg, a leader in the production of bitumen for road paving (modified bitumen, bitumen emulsions, albino bitumen, etc.), boasts a range of products, designed to meet the most demanding specifications. Thanks to the activities of its R&D centers in Lyon, France, and the two production facilities in Rome and Volpiano, the company is able to provide high-tech products of proven quality and high performance.
Kromatis, for example, is a clear bitumen that can be colored in different tints. This results in advantages in terms of safety (bicycle paths are one example) due to greater visibility. In some tunnels, white was used to increase brightness. Moreover, in particular landscapes, Kromatis offers the best solutions, in terms of decoration and integration with the territory (a case is the Pieve di Cadore dam). Kromatis is also resistant to low temperatures, has a high mechanical strength, it is easy and quick to apply, something that will please many motorists as road traffic can resume almost immediately.
STYRELF on the other hand, is a modified bitumen realized with a special production process patented by Total resulting in a high elastic asphalt, resistant to low temperatures and long lasting due to its reduced deterioration rate even in the presence of strong traffic. Furthermore, STYRELF allows to prepare draining and sound-absorbing asphalt and it is often used on motorways and airport runways
Finally, STYRELF INTAKT adds a greater resistance to aggressive chemical agents and its anti-kerosene properties make it ideal for airport runways as can be seen in airport such as Caselle in Turin and Fiumicino in Rome.