Asphalt Overlay. Without question the most common method of rehabilitation for flexible pavement is an asphalt overlay. There are many variations of this technique ranging from pavement planing and a thick asphalt overlay to a thin skin patch placed infrequently along a pavement. The existing condition of the asphalt pavement and the results of nondestructive testing dictate the most economical strategy. The pavement can be designed as a layered system.
Whitetopping. The construction of a concrete pavement on an existing asphalt pavement is termed whitetopping. An asphalt pavement provides an excellent base for a rigid pavement. The concrete pavement is designed as if it were a new pavement constructed on an asphalt base. The AASHTO design procedure can be used to design the concrete pavement, and the strength of existing pavement is utilized. A concrete overlay is an acceptable rehabilitation technique for flexible pavements beyond economical repair. However, construction is difficult unless lane lines are shifted permanently, and the thickness of the overlay makes elevation transitions at bridges difficult.
