A pure ceramic 3D printed artificial reef — stability and response

Artificial reefs (AR) are among the available methods to support local coral reef environments, mainly by providing shelter space and substrate for settlement. However, current AR design and fabrication methods designated for reef habitat regeneration have focused primarily on maximizing their size while encompassing higher rates of morphological complexity. Questions such as stability and durability of ARs designs have rarely been experimentally tested under this rationale. In this research initiative, two main approaches were used to assess the stability of experimental 3D-printed AR sets made of ceramic material. The first method was a practical on-site analysis that examined the assembly process of two identical AR sets positioned at depths of 15 m and 23 m, and later by continuous monitoring of their structural stability using photogrammetry. The second method applied in this research encompasses a physical testing campaign, carried out in a towing tank facility, to determine the particular hydrodynamic characteristics of the selected AR modules — under different environmental conditions. These unique parameters are subsequently used to calculate the actual loads operating on the AR modules at sea, as a function of both wave energy and in-situ depth. Both methods provided insight into the structural effectiveness of the abutted ARs and revealed that the concept of pure ceramic AR design without metal infrastructure is feasible to construct in a range of energetic sea conditions.