# Development of Korea Airport Pavement Condition Index for Panel Rating
## 1 Introduction  
The pavement condition index (PCI) is a quantitative index for evaluating pavement conditions which has been used in airport pavement management systems (APMS) since the early 1980s [1]; numerous airports in Korea and other countries have evaluated pavements using this index. The index has provided sound engineering data for pavement conditions and has particularly been used for preventing potential problems, such as foreign object debris (FOD), such as shown in Figure 1, and in decision-making processes for overall pavement maintenance and repair such as the prevention of additional damage due to cracks and the like. In particular, FOD may be an element of debris due to distress on the pavement surface, it is very important to maintain an appropriate pavement condition through evaluation. Ensuring proper maintenance of airport pavement and technical parameters is one of the key factors for ensuring operational safety in the ground maneuvering sector in terms of aircraft-airport surface contact [2]. However, [PERSON] and [PERSON] [3] pointed out potential problems and limitations when it comes to the applicability of the PCI calculation procedure in accordance with the differences between the environment at the time of development and the current environment. In particular, it is pointed out that PCI decreases after maintenance. [PERSON] et al. [4] classified a total of 13 distress types by combining the patching size classification and spalling location classification among the 15 distress types classified in ASTM D 5340. And a new PCI calculation method and a corrected deduct value curve (CDVC) for multiple distresses was developed, though the deduct value curve (DVC) was used without modifications. [PERSON] [5] considered the limitation of being unable to properly consider current pavement distresses in adjusting the distress types used for PCI evaluation or when placing more weights on main distresses. Various studies have been conducted to overcome these limitations. First, the Virginia Department of Transportation (VDOT) developed its own new pavement condition indicators based on the existing PCI [6]. An Italian study conducted a similar procedure [7]. They added two types of distress and developed a new density/deductive curve to apply it to their needs and pavement surface condition. In addition, in India [8], road pavement evaluation methods based on the Overall Pavement Status Index (OPCI) have been developed. The OPCI model includes four indicators: pavement distress index, surface roughness index, pavement structural capacity index, and skid resistance. In addition, it has been found that the ratings of the existing PCI developed for airports of various scales in the United States showed significant differences considering the management levels of Korean airports, which mainly consist of mid-sized and large commercial airports [9]. As a result of compared and examined deduct values (DV) in terms of the distress to verify that the PCI decreases after maintenance and repair if block cracks of a low severity level with a distress density of approximately 25% or higher are patched. Moreover, they pointed out the unreasonable problem where the pavement condition was satisfactory even though maintenance and repair were required. This is believed to be because of the communication problems between the maintenance and repair staff and decision makers [10]. This study was conducted to resolve these problems and to develop an airport PCI suitable for Korean circumstances. Accordingly, we analyzed the existing PCI calculation procedure, redefined the main distresses of Korean airport pavements by forming an airport pavement expert panel, and newly developed a DVC and a CDVC using the panel rating, which is an engineer's experience approach. Moreover, the field application results were compared and examined against the existing PCI to ensure the adequacy of the Korea airport pavement condition index (KPCI), which is calculated using the curves.