Analysis of Thin Overlays Over the Bituminous Road

Abstract— Thin overlays are widely used as a preventive maintenance and rehabilitation technique to enhance the performance and extend the lifespan of bituminous pavements. Applied in thicknesses typically ranging from 25 mm to 50 mm, these overlays serve to restore surface smoothness, improve skid resistance, and address minor surface distresses such as cracking, raveling, and oxidation. This study analyzes the effectiveness of thin asphalt overlays by evaluating their performance, material composition, construction practices, and long-term benefits. Emphasis is placed on their cost-efficiency, environmental advantages, and suitability for pavements that are structurally sound but exhibit surface deterioration. Field data, performance monitoring, and case studies from various transportation agencies are reviewed to assess service life and maintenance requirements. The findings indicate that when applied under appropriate conditions and with proper material selection, thin overlays can significantly delay major rehabilitation activities and reduce life-cycle costs. However, their limitations in addressing deep structural failures and susceptibility to reflective cracking must be considered. This analysis supports the role of thin overlays as a sustainable and effective pavement preservation strategy within modern asset management systems. Index Terms—Asphalt , seal coat, Aggregate.