Coastal erosion mitigation by the use of an optimized 3D printed Triply Periodic Minimal Surface Floating Porous Breakwater
Authors: Hasanabadi Amirhosein , Stolle Jacob , Pham Van Bang Damien , Hammouti Abdelkader 
Published: March 2024

Coastal regions are confronted with an escalating threat posed by the intensification of wave-induced erosion through rising sea levels and increased storm intensities, underscoring the critical need for innovative solutions to ensure effective coastal protection. Floating breakwaters as a possible optimal solution play a crucial role in land reclamation by facilitating the creation of recreational spaces, such as promenades, and enhancing aesthetical landscapes through tree plantations. Their significance lies in their ease of maintenance and the ability to be swiftly removed during stormy seasons, providing adaptable and sustainable solutions for coastal development. This study explores the potential of the Triply Periodic Minimal Surface (TPMS) floating porous breakwaters as an optimal approach, due to their intricate geometry and structural integrity which enhances the dissipation and dispersion of wave energy, to mitigate the impact of waves on vulnerable shorelines. TPMS structures offer a sustainable solution by being printable with re-use materials, promoting recycling, and aligning with the principles of a circular economy, thus contributing to eco-friendly coastal protection. Conducted in a controlled environment within a small-scale wave flume, our comprehensive laboratory-scale experiment focuses on assessing the performance of various TPMS structures under diverse conditions of wave and current generation. Systematically varying parameters, including TPMS architecture, unit cell size, relative density of porous structures, buoyancy depth (draft), and altering wave parameters and current rates, aims to elucidate the influence of these variables on the breakwater&#8217;s ability to dissipate, reflect, and transmit wave energy. The experiments involved exposure to various regular wave conditions generated by a plunger-type wavemaker, combined with different constant current rates to mimic realistic coastal scenarios. The controlled environment enables a nuanced understanding of how TPMS floating breakwaters respond to diverse wave dynamics, providing valuable insights into optimal design parameters. The performance evaluation is conducted using three widely known parameters: reflection coefficient (Cr), transmission coefficient (Ct), and dissipation coefficient (Cd) as they quantify the efficiency of wave energy absorption, transmission through the structure, and dissipation, providing key insights into the breakwater's ability to mitigate wave impact and protect coastal areas. To determine these parameters, wave separation analysis methods have been employed, including the method developed by Suh et al (2001), which considers the presence of simultaneous waves and currents, and the method developed by Zelt and Skjelbreia (1993), utilizing an arbitrary number of wave gauges. Anticipating that the outcomes of this study will contribute to the development of a novel coastal protection solution, we strive to strike a balance between environmental sustainability and effective wave attenuation. Furthermore, our research opens avenues for integrating optimal floating breakwaters with wave energy conversion systems, enhancing functionality and addressing both environmental and energy challenges associated with coastal protection.