# Methodology for the Concept Design of Locally Reinforced Composites
## 3 Demonstration of the Approach
### Analysis of the Deviation Factor and Stress Threshold  
The following section focuses on the effects of both deviation factor and stress threshold on the costs, displacement, and weight for the demonstration example given in Figure 8. The reference laminate is defined by a symmetrical UD 60\({}^{\circ}\)/0\({}^{\circ}\)/\(-\)60\({}^{\circ}\) laminate with a layer thickness of t = 2 mm (layer properties see Table 2). This lay-up was determined by analyzing the principal stress directions and is suitable for carrying the applied load cases, while having only small deformations. The cost, max. displacement, and weight of the reference laminate are shown in Table 2.  
To ensure comparability, for the base-laminate of the TT optimized part, the same lay-up as the reference laminate is applied, while the thickness of each layer is reduced to t/2 = 1 mm. Each reinforcement has a layer thickness of t = 2 mm and is applied symmetrically on the top and bottom faces of the base-laminate. For principal stress directions 1 and 2, the reinforcement areas and corresponding angles from the mechanical model are applied directly, as calculated by the mechanical model. As discussed in Section 2.1, the reinforcements for both principal stress directions might overlap. The maximum displacement, weight (base-laminate plus reinforcement), and costs are considered as target values. All values of the TT-optimized component are given as relative values, in relation to the reference laminate, where values below 1 indicate an enhancement compared to the reference laminate. The target values are analyzed for stress thresholds \(\upmu\) from 5% to 100% and deviation factors of 5\({}^{\circ}\), 10\({}^{\circ}\), and 15\({}^{\circ}\). The overall behavior of the target values, depending on the stress threshold, is shown in Figure 11, for a deviation factor of 5\({}^{\circ}\). Figure 11: Results from both mechanical and economic models (c\({}_{\text{d,max}}\) = 5\({}^{\circ}\)) for the demonstration example introduced in Figure 8. Cost, displacement, and weight from the tailored textiles component are given as relative values in relation to the reference laminate. In general, a contrary behavior of weight and costs, as well as of the max. displacement, can be observed. A decrease in the maximum displacement for high-stress thresholds occurs, due to an increase in the proportion of stress carried by the reinforcements. At the same time, costs rise as the component weight and the number of clusters increase. For the TT component, the displacement, weight, and costs can be reduced compared to the reference laminate using the proposed mechanical and economic models. For low and high-stress thresholds, the TT component has a lower performance (values > 1) than the reference laminate. In a range that is between approx. 67.5% and 85%, the TT optimized part shows significantly better performance than the reference laminate (values <1). In Figure 12, this feasible range is examined in more detail, giving the values for deviation factors of 5\({}^{\circ}\), 10\({}^{\circ}\), and 15\({}^{\circ}\). As an example for a deviation factor of 10\({}^{\circ}\): for the same displacement as the reference laminate, weight and costs are reduced by approx. 30% with TT at \(\mu\approx\) 67.5% for \(\text{c}_{\text{d,max}}=\) 10\({}^{\circ}\). The displacement is reduced by approx. 30% for the same weight and costs at \(\mu\approx\) 85% for \(\text{c}_{\text{d,max}}=\) 10\({}^{\circ}\). Between these points, any desired interstate can be chosen. As expected, low deviation factors show the lowest maximum displacement. However, simultaneously, the costs increase significantly. The maximum difference in cost and displacement is about 20% between \(\text{c}_{\text{d,max}}=\) 5\({}^{\circ}\) and \(\text{c}_{\text{d,max}}=\) 15\({}^{\circ}\).