THE USE OF SULFUR IN FLEXIBLE PAVEMENT ROAD CONSTRUCTION OPPORTUNITIES AND CONCERNS

Sulfur has been incorporated into asphalt mixture for a number of years in an attempt to combat various damage and failure mechanism that occur in flexible pavements at an increasing rate such as shoving, rutting, and raveling. Furthermore, the cost of road construction materials in particular bitumen is expensive. Hence, among the alternatives is by incorporating sulfur in the asphalt bound layers of the pavement structure. Sulfur is a major waste of by-product from gas and oil production that has potential for encapsulation in civil engineering purposes.
This study will cover on the use of sulfur in road construction opportunities and concerns. The utilization of sulfur on road construction has been known as Sulfur Extended Asphalt Modifier (SEAM). Opportunity for utilization of sulfur as partial substitute for bitumen in asphalt mixtures is a great application. Sulfur may make the asphalt more economical and may improve mechanical and durability properties such as increased stiffness and reduced permanent deformation.
In the asphalt mixture, sulfur crystallization will function as a structuring agent. Sulfur and asphalt is mix together above the melting point of the modified sulfur and when the blend cools, it solidifies. Then, the crystallization result is in different level of strengthening depending on the amount of modified sulfur and asphalt is ratio. The amount of sulfur added is important as it will affect the performance of pavement structure. However, handling and safety issues need to concern due to the oxidizing of sulfur dioxide will produces the poisonous gas that was toxic.