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4.3 Inspection procedures
The evaluation of pavement condition included consideration of specific problems that existed in the pavement. This requires a determination of the types and
causes of distress, as well as the extent of pavement deterioration. Pavement inspection is conducted on inspection units. An inspection unit is a small segment of a
pavement section or management unit selected of convenient size which is then inspected in detail. The distress found in the inspection unit is used to calculate the
PCI for the inspection unit inspected. The PCI of the inspected inspection units in the section are then used to represent the condition of the entire section.
When a small area of pavement is found to be much worse than the majority of the pavement, it can be inspected and identified as a special inspection unit. This
was used to identify areas of localized deterioration such as an area damaged by utility cuts, crossing of construction traffic or other localized problems. A weighted
average was used to calculate the PCI when special inspection units are inspected. The inspector inspects the sample unit by walking the inspection unit or
standing on the curbshoulder, and recording the type, severity and amount of each distress present in the inspection unit. The type, severity and amount must correspond
to those defined in this distress identification manual. The quantities and severities should normally be estimated using measuring techniques as accurate as pacing when
the inspector can walk the inspection unit and by visual estimation when he stands on the curb or shoulder ASTM, 1999.
The inspection method is designed to allow the calculation of a composite rating index called the pavement condition index PCI. The steps for determining the
PCI of an inspection unit are shown in analysis of data inChapter III.The PCI scale is shown in figure 2.20 in Chapter II .The distress types ,severity levels descriptions
must be carefully followed since they were used in the development of the deduct curves. Failure to do so could invalidate the PCI calculated.
THE study road lie in north east part of Libya in Koms city .Type of road is secondary road; it is link by length 20 km between city center and Mslata village. This project
was a field study of a road length of 1000 m two directions, and was divided into 10 parts a length of 100 m of each part.
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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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