In a civil engineering management system, pavement’s relative ability to serve traffic over a period of time determines its official pavement performance. The process of pavement evaluation is used to find its level of performance, and it typically consists of a system of objective measurements. These systems vary in establishing maintenance priorities, determining maintenance strategies, and predicting pavement performance. No matter the system, they all use these pieces of pavement quality to reach their conclusions.
- Roughness: In the evaluation of pavement, roughness refers to irregularities in the pavement surface that would negatively affect the quality of riding in a vehicle. Pavement’s roughness will also have a monetary impact on drivers affecting the operating costs of vehicles, fuel consumption, and maintenance costs.
- Skid Resistance: When a tire is prevented from rotating slides along the pavement surface, it creates a force known as skid resistance. This data is important when evaluating pavement because pavement with inadequate skid resistance will lead to a higher number of skid related accidents. As a majority of agencies who manage roadways have an obligation to make the roads reasonably safe for drivers, monitoring skid resistance is an important duty.
- Surface Distress: As a slightly broader data measurement, surface distress covers any sign of pavement performance that indicates it is unfavorable or subject to impending failure. Forms of surface distress can be categorized in fracture, distortion, and disintegration. Fractures form from excessive loading or fatigue and can be in the form of cracking or spalling. Distortion refers to when pavement becomes deformed and disintegration occurs when pavement is stripping or raveling.
- Deflection: In pavement evaluation, the magnitude and shape of deflection is dependent on several factors. This includes the volume and type of traffic that uses the pavement, how temperature affects the pavement structure, the pavement’s structural section, and how moisture impacts the pavement structure. Deflection is measured in a pavement surface’s vertical deflected distance as a result of a load applied to the pavement.
In the United States, it is estimated that more than one-third of the country’s major roads are in poor or mediocre condition. Pavement evaluation is a critical method of improving these roads and predicting when they will need repairs.