March 2025
The substrates were produced in two halves to facilitate the extrusion process and the inclinations of the shape. Finally, the halves will be joined and secured at both the upper and lower ends using metal hooks. This concept will function as a floating artificial reef, similar to aquaculture methods, to help promote a different type of marine habitat.
February 2025
Given that the large-scale reef was printed using only Saint-Gobain cement to validate the shape and the extrusion manufacturing method, smaller substrates were produced to be tested with the formula developed in this research. This formula consists of crushed mussel shell waste, metakaolin, and CEM I cement.
December 2025
Final stage of the assembly of the two parts completed. The artificial reef has been assembled and sealed with metal rings and rods, which allow the structure to be lifted onto the truck by a crane. The reef will be transported to the area near the implementation site in the sea, in southern Portugal.
December 2024
The second phase of 3D printing involved rotating the first part of the base 180º, using cranes and fixing mechanisms, to print the upper part of the reef. This phase required careful design to ensure layer bonding. The second part, weighing 350 kg, is now drying for the next seabed implementation phase.
November 2024
The base, weighing approximately 470kg, was the first part of the reef to be printed. This pilot structure was produced using the formula recommended by 3D Weber Saint-Gobain and will primarily serve to evaluate all aspects of shape, logistics, and ecological functions to attract marine organisms. Smaller structures will be produced using the developed mortar to assess all aspects of this research, including shape and chemical composition.
November 2024
The final scaled prototype was produced to validate the assembly mechanisms and manufacturing process, ensuring full control over all phases of production.
November 2024
The 3D printing method was planned in two parts: the base and the top, to optimize print quality and material usage. Supporting materials were prepared, including the base for printing the reef, as well as systems and components for fixation and transportation, such as crane lifting mechanisms.Samples were prepared with the developed mortar using standardized molds for mechanical testing.
September 2024
Compression and flexural tests were conducted on the samples to document the results for potential large-scale applications.
September 2024
Samples were prepared with the developed mortar using standardized molds for mechanical testing.
September 2024
A slump test was conducted on the mortar to validate and document the consistency of the developed cementitious mix.
August 2024
The developed mortar, composed of mussel shell and metakaolin, was validated, and the design showed excellent results, proving ready for full-scale production.
July 2024
The initial printing was performed using ceramic paste to validate the design, ensuring that shapes and curves did not require simplification. Once completed, the ceramic prototype was cured in a kiln to achieve optimal mechanical strength. The results were highly favorable.
July 2024
The mortar previously used for substrate fabrication was tested in a manual extrusion sleeve to assess its consistency and adjust proportions for 3D printing extrusion. Mussel shell, metakaolin, CEM and plasticizer was used.
July 2024
Renderings were produced for participation in international projects and to visualize the structure’s appearance with the layer-based manufacturing process.
June 2024
Several scaled models were printed to test the designed features: modular system, organic shape, open and tunnel refuge areas, promotion of benthic organism colonization, and defined support points for logistics and transportation.
May 2024
Various morphologies were developed to test the functionality of the structure, considering the limitations of the manufacturing method: 3D printing through cement extrusion.
January 2024
Following the analysis of all results obtained during the investigation, the briefing phase has begun to define the concept and shape of the artificial reef, which will be printed using cementitious mortar extrusion.
November 2023
The mortar developed and tested in the aquarium showed excellent results compared to 3D Weber cement, with significantly lower sedimentation levels and minimal pH increase.
November 2023
Substrates made with 3D Weber Saint-Gobain mortar showed excessive sedimentation at the bottom of the container, highlighting the need for pre-conditioning before use with marine organisms.
November 2023
The ICP study was conducted on the mortar with the best performance in both pH variation control and coral fragment growth potential: M4 (mussel shell + metakaolin + CEM I). Additionally, the 3D Weber material (a cement-based mortar designed for 3D extrusion printing) was also tested, along with natural seawater for comparison. The natural environment was simulated by placing the substrates in 1000ml containers equipped with water flow motors and glass lids to prevent evaporation.
October 2023
After 315 days, some substrates showed nearly complete coverage of their surface by coral growth, with favorable indicators of expansion. The study confirmed vertical coverage capability and the performance of the various materials used. None of the mortar formulations showed any instances of coral mortality.
August 2023
Several substrates naturally hosted other coral species (originating from colonies within the aquarium), which attached themselves and grew alongside the original fragments on the same substrate.
July 2023
Substrates primarily composed of mussel shell, in their various formulations, showed the greatest horizontal and vertical expansion of coral fragments.
July 2023
All substrates demonstrated excellent conditions for promoting the attachment and colonization of coralline algae, a key indicator for supporting coral growth.
March 2023
Small fragments of the coral species Montipora danae were placed at the center of each substrate. The substrate’s arms securely held the coral, protecting it from aquarium currents. This system eliminates the need for marine epoxy adhesives, promoting a more sustainable and natural method of coral fixation and adaptation.
December 2022
The substrates were pre-conditioned in seawater for 7 days before being placed in the aquarium with coral fragments.
December 2022
In addition to the raw materials—limestone, dolomitic sand, mussel shell, and fossil coral skeleton—new variations were introduced, including pozzolanic materials, to study their effect on pH control: fly ash, silica fume, brick dust, metakaolin, rice husk ash.
November 2022
The manufacturing process using silicone molds was once again employed to produce the larger substrates.
November 2022
A larger substrate measuring 45 x 45 x 55 mm was developed to study coral propagation through fragmentation, placing the substrates in an aquarium to observe coral preferences and growth rates.
October 2022
In 100ml containers, all substrates made from different material variations were tested to identify which material released the most sediment and caused the greatest pH increase in the water over a set period.
October 2022
The pH variation in seawater was studied across different volumes of 1000ml, 400ml, 100ml, and 50ml. The study aimed to monitor changes in this parameter over time.
August 2022
The main hypothesis for the coral larvae’s death was sediment accumulation in the substrate pores. Excess sediment was observed at the bottom of the containers and on the substrate’s surface, suggesting the need for pH control in these areas and a pre-conditioning process in saltwater before exposure in such studies.
August 2022
The different substrates were placed in containers with saltwater, where coral larvae from Portuguese waters were naturally reproduced. The larvae were quickly attracted to the substrates, particularly fossil coral skeleton and limestone, but died in the following days.
July 2022
The different materials were cast into molds to create coral propagation substrates. These substrates were sent to the University of Algarve’s laboratory for larval colonization studies.
July 2022
The study aims to assess how selected materials impact coral settlement, growth, and substrate interactions, focusing on chemical composition, texture, and morphology. The four raw materials selected were processing to obtain the desire granulometries for molding process.
June 2022
Fossil coral skeletons from the aquarium industry were used, with no live coral involved. Calcium carbonate from these fossils may favor coral settlement, as larvae often settle on biogenic carbonates like dead coral rubble. An ultrasonic bath was used to clean the samples, removing organic residues and old substrates.
May 2022
Various materials were tested, including limestone, mussel shell, fossil coral skeleton, dolomitic sand, and cement variations with different percentages of calcium carbonate.
April 2022
Based on the developed 3D design, PLA substrates were 3D printed for mold fabrication, enabling the production of a large quantity of substrates with different materials.
March 2022
A small substrate measuring 20 x 20 x 15 mm was developed to study the natural attraction of coral larvae to the material and its shape.
October 2021
Based on the study conducted during the master’s degree, the results obtained from coral propagation substrates were considered for the new study in the doctoral program.