# Complex Method of Airfield Pavement Condition Evaluation Based on APCI Index
## 5 Results
### Output Data  
The airfield pavements are evaluated according to the criteria for assessing the technical condition of the pavement, based on the APCI values obtained. The criteria were developed on the basis of multiannual field research.  
In order to determine the scale of the values of the pavement condition indicators, seven categories of the technical condition of the airfield functional element pavement were introduced. The entire range of the selected variable, from the minimum to maximum, is divided into a certain number of compartments with an even length. These cases for which the values of the selected variable belong to one interval, consist of a common category. In a simplified scale, there are three decision-making levels describing the technical condition of the airfield functional element. A class determining the pavement condition was assigned to each level. The first one is the desirable level, which includes new, renewed and operated surfaces. It is predicted that over the next five years, these surfaces will not require planned renovation works. The warning level, indirect, identifies the pavement condition as such in which it is justified to perform detailed testing towards performing this status. The latest is a critical level, determining the immediate performance of technical and consumables tests to determine the procedures to improve the pavement condition. Figure 4 shows the process of assessing the technical condition of the airfield functional element pavement based on the designated APCI together with criteria.  
The APCI scale can be presented in a simplified way as:  
* Appropriate (APCI = 71 \(\div\) 100),
* Degraded (APCI = 56 \(\div\) 70),
* Unsatisfactory (APCI = 0 \(\div\) 55).  
The critical value of the APCI is the value, after reaching which the technical condition of the pavement leads to rapid deterioration. Table 3 shows the determined values of the APCI based on the calculated unloaded and weighted indicators by limit values and occupied area. The given values of the APCI should be used in the process of comprehensive assessment of the technical condition of the airfield's functional element pavement made in cement and asphalt concrete technology.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Operating Parameters**} & \multirow{2}{*}{**Degradation**} & \multicolumn{2}{c}{**Load**} & \multicolumn{2}{c}{**Anti-Skid**} & \multirow{2}{*}{**Evenness**} & \multicolumn{2}{c}{**Bond**} \\  & & **Capacity** & & **Properties** & & **Strength** \\ \cline{2-7}  & \(w_{D}\) & \(w_{N}\) & \(w_{Wpp}\) & \(w_{RL}\) & \(w_{RT}\) & \(w_{Wod}\) \\ \hline \(D+N\) & 0.40 & 0.60 & & & & \\ \(D+N+R_{L}+R_{T}\) & 0.30 & 0.50 & & 0.10 & 0.10 & \\ \(D+N+Wpp\) & 0.30 & 0.55 & 0.15 & & & \\ \(D+N+R_{L}\) & 0.30 & 0.60 & & 0.10 & & \\ \(D+N+R_{L}+R_{T}+Wpp+Wod\) & 0.25 & 0.40 & 0.15 & 0.05 & 0.05 & 0.10 \\ \(D+N+R_{L}+R_{T}+Wpp\) & 0.30 & 0.40 & 0.15 & 0.05 & 0.10 & \\ \(D+N+R_{L}+Wpp+Wod\) & 0.25 & 0.40 & 0.15 & 0.10 & & 0.10 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Weights for various combinations of operating parameters of the airfield’s functional element pavement for calculating the APCI.  
In APCI\({}^{\text{G}}\), APCI\({}^{\text{F}}\), APCI\({}^{\text{wG}}\) and APCI\({}^{\text{wF}}\) columns present criteria for the value of the APCI index designated on the basis of weighted or non-loaded indicators determined by the surface or limit values methods. The general assessment criteria for the technical condition of the airfield's functional element pavement based on the APCI was adopted as an average value from the above variants.