|M.Sc Student||Abu Ahmad Muammar|
|Subject||Light Reflection from Different Asphalt Types|
|Department||Department of Civil and Environmental Engineering||Supervisors||Professor Tomer Toledo|
|Dr. Wafa Elias|
|Full Thesis text - in Hebrew|
Road markings constitute a part of the signposting system of the road network for the purpose of ensuring a fluid traffic flow and a high safety standard for road users.
The markings materials in use today by the National Roads Company of Israel are conventional paint (solvent-borne). These materials are characterized by a short life span (12 months) thus requiring repeated maintenance. The direct costs can mount up to tens of millions of shekels per year. Moreover, these operations are accompanied by additional costs caused by road closures, that results in traffic disruptions and delays.
As of today, the optical features of the pavement’s surface aren’t part of the factors in the choosing process of pavement types by the National Roads Company of Israel. On the other hand, in the field of optical engineering there is a significant importance to the optical features of a pavement’s surface.
The purpose of this research is to study light reflections from different types of asphalt and the effect it has on nighttime accidents. Moreover, this research investigates the effect of different factors on light reflection from road markings, also compares coefficient values of light reflection (RL) and contrast of road markings on different types of asphalt pavements. Further, it studies the effect that the road marking’s location on the road has on light reflection.
This research is based on databases taken from National Roads Company of Israel, govmap.gov.il (the official maps site of Israel), Central Bureau of Statistics, and field tests using the RetroTek-M device. The databases included data on road type, AADT (annual average daily traffic), asphalt type, the last date of asphalt maintenance job and last date of road markings repaint job. In this research, we focused on multilane rural unlit roads, and collected the number of relevant accidents during day and night from all the chosen road segments from the Central Bureau of Statistics website.
The research focused on three different asphalt types: 1. Stone mastic asphalt (SMA) which consists of basalt aggregate only. 2. Superpave asphalt mixture, which consists of basalt aggregate only. 3. Superpave asphalt which is a mixture of basalt aggregate and dolomite aggregate.
Research results show that the white street markings have a greater light reflection coefficient and contrast from yellow markings, also white road markings located on the left side of the road have a greater light reflection coefficient and contrast than the ones located in the middle of the road. Moreover, road markings on asphalt type 2 have a greater initial light reflection coefficient and contrast than markings on asphalt type 1. Road markings on asphalt type 1 have a greater initial light reflection coefficient and contrast than markings on asphalt type 3. also, the research showed that there is no significant correlation between asphalt type and the ratio between nighttime and daytime accidents.