GNGTS 2016 - Atti del 35° Convegno Nazionale

442 GNGTS 2016 S essione 2.3 the latter. Conversely, the algorithm keeps thickness in the external columns as low as possible in the same range of ductility. When the thickness in the internal columns reaches the maximum allowed value (2 mm in this investigation), there is still room for improvement in ductility, at expenses of great increase in thickness of FRP applied at the external columns only (see Fig. 3, “����� ���� �� ��� ��������� ��� ������������� �� ��� ����� ������ �� ���������� ���� ��������� Floor 1”�� �� ��� ��������� ��� ������������� �� ��� ����� ������ �� ���������� ���� ��������� ). On the contrary, the reinforcement at the other floors is remarkably less important in terms of global response of the frame, as it can be seen in Fig. 3, ������ �� ��� ������ �� “Floor 2” and ����� � “Floor 3” charts. Because of its negligible effects on the ductility increase and substantial contribution in the total cost, the FRP thickness in the other floors is consequently kept as low as possible. From a practical point of view, no reinforcement is needed at the second and third floor, leading to remarkable savings. In addition, it must be �������� ���� ��� ������ ����� ��������� ��������� observed that all Pareto Front solutions displayed Fig. 3 – Dependence of ductility on FRP wrap thickness, as obtained for internal and external columns at each floor.