## 3 Results
### Creation of RUT Deterioration Function  
The other parameter evaluated during the operation of the APT facility was the RUT resistance. In the first pre-operative stage, the pavement surface was measured via total station and ZScanner and a point cloud of the pavement surface was created. Then, two average sections in the middle of the APT track were selected for cyclic monitoring and evaluation. The profiles were selected in sections where the loading unit moved at a constant speed. The results of the RUT progress in relation to the DAL loading are shown in Figure 12 color coded for 0 (light blue), 200,000, 400,000, 450,000 and 500,000 (red) load cycles. The two APT functions are shown in Figure 13 (right) and an average APT function is presented in Equation (10). Two complementary functions were created from LTPPM sections located in Slovakia, the Zilina region (GPS 49.140747, 18.718033 and 49.209219, 18.784072). These functions are shown in Figure 13 (left) and an average function is presented in Equation (11). Both functions are shown in Figure 14, with an average function combining APT and LTPPM average functions presented in Equation (12). The regression analysis data for this function are shown in the Supplementary Files. \[p_{x}=-3.7867x^{3}+5.5442x^{2}-2.7578x+0.9998 \tag{10}\]  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Year** & **Strain Increase (Mpa) of** & **Strain Increase (Mpa) of Base** \\  & **Wearing Course** & **Course** \\ \hline
1 & 0.4427 & 0.6243 \\
2 & 0.4702 & 0.6733 \\
3 & 0.4977 & 0.7223 \\
4 & 0.5252 & 0.7713 \\
5 & 0.5527 & 0.8203 \\
6 & 0.5802 & 0.8693 \\
7 & 0.6077 & 0.9183 \\
8 & 0.6352 & 0.9673 \\
9 & 0.6627 & 1.0163 \\
10 & 0.6902 & 1.0653 \\
11 & 0.7177 & 1.114  
poor-to-very poor conditions. AADT is 4522 with an annual traffic growth of 3%. Overall rehabilitation costs are EUR 215,996, the life cycle is set to 20 years, and the discount rate is 3%. The generic exponential degradation PPM based on the generic exponential degradation from Equation (9) yields the results shown in Figures 15 and 16. The overall results are as follows:  
Internal rate of return: 6.756%. Net present value: EUR 75,270.26. Payback period: 2031. The APT-derived polynomic degradation PPM based on the APT/LTPPM-derived polynomic degradation yields the results shown in Figures 17 and 18. The overall results are as follows:  
Internal rate of return: 3.419%. Net present value: EUR 7568.92. Payback period: 2036. A comparison of the presented PPMs is presented in Table 5.  
The economic payback year as an economic indicator is the year in which the social benefits (social savings), minus the operating costs, reach the investment costs. An acceptable investment construction project achieves a payback year before the end of the useful life of the construction work. The importance of this indicator is low and serves an informational purpose. The economic internal rate of return is a key indicator in the evaluation of this project because it provides a result that is not influenced by the discount rate and allows projects with different financial volumes to be compared. The internal rate of return (IRR) should be higher than the interest rate of any loan on which the private investment is to be made. The internal rate of return--IRR--should be higher than the opportunity cost, i.e., the rate of interest that can be achieved by other conventional investment methods (e.g., by depositing money in a monetary institution). The internal rate of return--IRR--should be higher for public works than the prescribed discount, which reflects the externalities on the project and is a guarantee that the investment in question will not be at a loss even under certain expected inflationary developments. The importance of this indicator is crucial. The economic net present value is the value of the discounted economic flows of the project in financial terms.