Force transfer mechanism on fastener section of mechanically anchored waterproofing membrane roofs under wind pressure during typhoons

The wind pressure, billow of a PVC sheet, and fastener load of a mechanically anchored waterproofing membrane system on a building rooftop were measured during a typhoon. The results showed that the waterproof sheet billowed upward, and the height of the billow was greater on the windward side that was under higher negative pressure. The axial and lateral forces acting on the fastener of the waterproof sheet were measured by a six-component force transducer, and it was found that the lateral force acting on the windward side of the fastener was larger. The tensile force acting on the fastener section was calculated using an equation for rooftop wind pressure. Finally, the method used to determine the fastener's position and the types of materials best-suited to cope with wind pressure on the roof were proposed, and the safety of this waterproof system was evaluated.

► The behavior of a waterproofing membrane was analyzed during a typhoon. ► The billowing height of the waterproofing membrane was higher on the windward side. ► The axial and lateral forces on the fastener were measured by a six-component load cell. ► The tensile force of the fastener increased with the wind pressure. ► The fastener distance necessary for the waterproofing membrane system under wind pressure was calculated.