The Aviorimesse 4-5 at Fiumicino Airport, designed in the late 1970s by Prof. Eng. Riccardo Morandi, are two twin hangars intended for the maintenance of Boeing 747 aircraft. The roof is the structure’s most distinctive feature. At the front, it consists of parallel pre-stressed beams, while the central and rear sections feature a tensile structure made of post-tensioned fabric panels, arranged at regular intervals (4.45 m) and functioning as cables with negligible flexural stiffness. The membranes are connected by slabs and anchored at the ends to edge beams, which are also post-tensioned and perpendicular to the membranes. The roofing system transfers loads to the vertical structures through stays anchored to the edge beams.

DIAMONDS carried out special inspections to verify the condition of pre-stressing cables within the roof membranes. Activities included the preliminary identification of the cables using ground-penetrating radar, followed by video-endoscopic surveys and high-precision ultrasonic tomography to identify potential voids inside the metal sheaths.