14 DAY TRIAL // Potholes are the nightmare of any driver.
Fixing asphalt damage caused by water infiltration comes with a great monetary cost and produces extra traffic delays as roads must be often closed during repair work.
But in the asphalt technology, the way water induces damages in the asphalt structure is not a well-known process, a fact that does not help in improving the asphalt's quality. This is going to change as Delft PhD candidate Niki Kringos has modeled the damaging influence of water and traffic on asphalt in a particular model of the American asphalt mixtures.
The water-induced asphalt damages are high even more in the Netherlands, where extremely open asphalt concrete (ZOAB) is employed: this must be repaired once every six to nine years.
"It is better to prevent asphalt damage than to simply keep repairing it." said Kringos.
Asphalt deteriorates its structure due to a mix of infiltrating water and the ongoing burden of moving vehicles. The road surfaces are negatively affected by the water due to its effects on the material qualities of the asphalt chemicals and their binding.
Kringos used a computer program developed by herself to model the deterioration in asphalt coming from the mixed action of water infiltration and mechanical load. The computer simulations revealed as crucial measuring the main variables inducing water damage (like the maximum moisture retentiveness, the moisture diffusion and the binding strength of the various asphalt components) for each individual component of the asphalt.
Slight differences deeply impact the level of asphalt damage. Kringos is now adapting her program to ZOAB.
The breakthrough approach can lead to better material selection, better maintenance planning and advanced asphalt mixture optimization producing asphalts with longer life.
In 2006 Kringos was the first European scientist to receive an annual PhD award from the Association of Asphalt Paving Technologists (AAPT) in the United States, for her innovative work.