## 4 Results
### CAE ANN Results for Multi-Parametric (mD) Model  
Figure 5 shows the results of a two-parametric model for the two input parameters, namely, construction span and cross-section width, and different output parameters: cross-section height (a), cross-sectional area (b), moment of inertia of the cross-section (c), mean stress in the cross-section (d), and quantity of cables (e), both in the use phase and in the total area of cables in the construction phase (f). Note again that the darker areas in the graphs indicate more reliable results. The highest density of data is in the range of 35 to 45 m for the construction span and in the range of 12.5 to 14.5 m for the cross-section width (the results from Equation (8) were used to determine this; we can also see that the darker areas indicate regions with higher data density). This outcome was expected because these spans and cross-section widths match the typical size of bridge structures in Slovenia and are best suited for the incremental launching technology. The results in Figure 5(a) prove that the construction span has a large influence on the height of the cross-section, while the width of the cross-section has a lesser influence. Figure 5(b) shows that the simultaneous increase in construction span and the width of the cross-section results in an increase in the cross-sectional area. Both input parameters have comparable influence in the normal ranges that are displayed at the axes. Figure 5(c) reveals that the construction span has a large influence on the moment of inertia of the cross-section, while the width of the cross-section has lesser influence. The construction span has a bigger impact on the bending moments of the bridge structure, which in turn has an impact on the vertical displacements. The statics and mechanics of solid bodies provide a clear physical foundation for the results stated. The results in Figure 5(d) show that in the range of the cross-section width of 12.5 to 15 m, the construction span has a significant influence on the mean stress in the cross-section during the use phase. In the range of 12 to 12.5 m for the cross-section width, there is a transition in the influence of the construction span, which decreases significantly in the range of 12 to 11 m for the cross-section width. However, since this is in the area with lower data density, the results are less reliable. In the region with the maximum data density, the mean stress values vary from 5.0 MPa to 5.4 MPa. Figure 4: Results for the total area of prestressed cables in the construction phase (a) and use phase (b), depending on the construction span (horizontal axis) and cross-section width (vertical axis). Figure 5e shows the quantity of cables in the use phase. As the construction span increases, the quantity of cables increases, because the bridge structure must bear larger internal forces that do not increase linearly with the increase in construction span. In the range of smaller cross-section width (11 to 12.5 m) and smaller construction span, the cross-section width also affects the quantity of cables. According to the findings in Figure 5f, the cross-section width and the construction span have a similar impact on the total area of cables in the use phase in the range of 11 to 12.5 m for the cross-section width. The demand for a greater total cable area in each cross-section increases as the construction span and cross-section width increase, which is a result of increasing internal forces caused by the increased values of both parameters. Figure 5: Results of two-parametric CAE ANN models for two input parameters (construction span—horizontal axis, cross-section width—vertical axis) and different design output parameters. Furthermore, Figure 6 shows three-parametric results. The input parameters are slenderness (the ratio of the construction span to the height of the cross-section), the width of the cross-section and the height of the cross-section in Figure 6a,b, and the construction span, width of the cross-section, and height of the cross-section in Figure 6c,d.