An Innovative Construction Technique for Curved Structures

In the present paper, an innovative, recently patented technique for the construction of a curved structural member without scaffolds is proposed and illustrated. It consists of a Hinged Lifting Arch (HLA), using Fiber-Reinforced Polymer (FRP) bonded strips. In detail, a series of blocks are cut following an arch geometry and then aligned on the ground floor to bond a composite on their top surface. Moreover, impregnation of the polymeric adhesive is not allowed at the extremities of each block. The fiber sheet is applied continuously along the entire extrados. In this context, hinges are introduced, and the FRP-connected blocks can easily rotate in the opposite direction around the contact ends (i.e., hinges). Finally, the middle block is lifted up, and the arch takes the desired shape. Moreover, an analytical model is proposed and discussed for designing the proper aspect ratio of the blocks in order to ensure full mutual contact when the HLA is completely lifted. The advantages of the proposed technique relate to the absence of scaffolds and improved seismic strength against horizontal loads, thanks to the presence of the FRP, which limits the occurrence of hinges at the extrados.