Total 574 words used.
Yanbu Industrial City is located 350 Kilometers northwest of Jeddah. It plays a major role in Kingdom’s gross national income. Royal Commission at Yanbu Industrial City, Saudi Arabia was keen to raise the efficiency of its roads network. Our goal is to provide a safe roads network with high-quality specifications without defects.
Roads in Yanbu Industrial City were frequently damaged due to the extensive use of trucks mainly on highways and roads in industrial areas, resulting in asphalt rutting, cracks, bleeding, etc. (Figure 1). Furthermore, the annual average number of heavy trucks entering the city is more than 4.5 million trucks between the period 2019 and 2021.
The Royal Commission launched a project to evaluate the roads network in the city by using roads evaluation equipment that has the capability of deducting roughness, rutting, cracks, surface distress, and deflection (Figure 2, 3). Along with the evaluation project, rehabilitation projects were initiated for the poorest condition roads. It was found that a total area of 3,425,114 square meters of asphalt surface needs to be rehabilitated. Moreover, most of the damaged asphalt surfaces are found in roads mostly used by heavy trucks.
The Royal Commission conducts studies to overcome the asphalt pavement deformation and found three passable solutions:
- Resurfacing with the existing asphalt mix design (Marshall Mix Design)
- Use Reinforced Concrete pavement instead of asphalt
- Use of Super Pave Mix Design (Superior Performing Asphalt Pavements)
Royal Commission used to pave by Marshall Mix Design for all roads network along with all rehabilitation projects in the past. Marshall Mix Design method is very popular because of its relative simplicity, economical equipment and proven record.
Construction of asphalt pavement using Marshall Mix Design method is relatively economical but it has some major drawbacks:
- Less pavement strength
- Low resistance for rutting and cracking
- Short service life
- Requires regular maintenance
Due to the increment in traffic volume, especially heavy trucks, The Royal Commission decided to divide the 3,425,114 sq m of asphalt to three groups. The first group was rehabilitated by Reinforced Concrete Pavement. However, this application was limited to intersections with rutting problems due to the high cost, less resistance for transverse cracks and increased pavement noise of this method.
The second group consists of roads that lightly used by trucks and mostly used by passenger cars. This group was rehabilitated by Marshall Mix Design with a total area of 728,572 sq m.
Since Marshall Mix Design was found to be not suitable for all different types of traffic in the city along with being inefficient and uneconomical with time. The third group was rehabilitated by Super Pave Mix Design that includes all roads used by heavy trucks and all the roads in the industrial area.
Thus, a wearing course was applied by Super Pave Mix Design on the existing asphalt base course having Marshall Mix design. This procedure established the precedent in the world, this method is called environment-friendly asphalt layer in Industrial Roads (Green Roads).
The Super Pave Mix Design method was designed to replace Marshall Mix along with the replacement of compactors by a gyratory compactor and the compaction effort. Thus, a total area of 1,185,306 sq m was paved by Super Pave Mix.
The advantages of Super Pave Mix Design are:
- Reduced the amount and severity of pavement distresses
- Improved stability
- Improved flexibility
- Improved durability
- Improved riding quality.
- Less pavement noise
- Low maintenance cost.
- Long service life
