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Inspection of all pavement section may be necessary, however, such inspection require considerable effort and time, especially if the section is large such as the road
that chosen. Therefore, the sample selected randomly by length 1000 m, may be it has been allow adequate determination of the PCI for road.
4.4 Data and Types of pavement distress
An asphalt pavement, when designed and constructed properly, will provide years of service. All pavements will eventually require some type of maintenance.
Asphalt pavements for parking facilities may require an application of sealer just to maintain or give a new appearance to the pavement for aesthetic reasons. Pavements
continually undergo various types of stresses that induce minor defects into the pavement Lavin,
2003. The early detection and repair of defects in the pavement will prevent minor distresses
from developing into a pavement failure. The identification of the distress aids the engineer or maintenance professional in identifying what caused the distress and the
required approach in repairing it. Cracks and other defects start appearing very small and are usually only detectable when walking along the pavement.
For entire section inspections, the inspector walks over each sample unit, measures each distress type and severity, and records the data on the Asphalt Pavement
Inspection Sheet. The letter L low, M medium, or H high is included along with
the distress number code to indicate the severity level of the distress. Distresses and
severity level definitions are listed in Chapter 2. To understand which repair to choose, it is important to understand the distresses that
occur in a pavement David, 2006. Assessing condition of pavement by visual observation and recording of types of defects on the surface layer of the pavement.
And include elements to assess the situation visually as follows: 1.
Type of distress 2.
Severity of distress 3.
Density
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The following sections describe he major problem that found in area of study during the field condition surveys:
4.4.1 Longitudinal Cracks
Low severity Medium severity High severity
Figure 4.2 Severity levels of longitudinal cracking
a. Description
Cracks parallel to the pavements center line or lay down direction. They may be adjacent to the pavement edge. Usually a type of fatigue cracking.
b. Problem
Allows moisture infiltration, roughness, indicates possible onset of alligator cracking and structural failure.
c. Possible Causes
Pavement that is fatigued or worn out from heavy traffic especially that due to high pressure truck tires; an unstable base; poor Construction.
d. Options for Repair Cures
Also treatment these cracks depend on the severity and intensity. In the case of low severity do not do something in the medium severity resort to fill the
cracks. In the case of high severity use overlays surface, or implementing to thin overlay.
