Experimental characterization of indented dry connections for precast double‐curved concrete shells

Abstract This paper presents the experimental validation of a connections system to connect segmented precast long‐span thin‐shell structures made with lightweight ultra‐high‐performance fiber‐reinforced concrete (UHPFRC). The work comprises the segmentation of the large‐span ultra‐thin shell to meet the requirements of prefabrication (construction and transport limitations), and the design and characterization of the connections. Once the assembling of the shell required the use of post‐tensioned unbonded prestressing, an indented dry connection was chosen. The connections are experimentally characterized with in‐plane and out‐of‐plane shear tests for different prestressing levels. The results are presented and discussed, demonstrating the balanced behavior of the indented dry connection under shear loading. The connections exhibited high ductility in shear, capitalizing on the use of a UHPFRC to fabricate the shell. The prestressing also demonstrated its efficacy, significantly enhancing both the stiffness and the capacity of the indented dry connection.