Hydraulic stability of interlocking modular hexagonal artificial reefs under varying water levels
DOI:
https://doi.org/10.33175/mtr.2027.289775Keywords:
Artificial reef; Hydraulic stability; Interlocking; Modular reef; Physical model testAbstract
Artificial reefs are increasingly used as submerged coastal protection structures. However, their performance may be compromised when individual units slide, roll, scatter, or progressively displace under wave loads. Although geometric interlocking is often assumed to enhance modular reef stability, its influence on stability response under varying water levels and wave conditions remains insufficiently quantified. This study experimentally evaluates the hydraulic stability of new Interlocking Modular Hexagonal Artificial Reefs (IMHAR) using physical model tests in a wave flume. The interlocking and non-interlocking arrays are tested at a 1:15 Froude scale using seven multilayer configurations, three water levels (Low Water Spring (LWS), Mean Sea Level (MSL), and High Water Spring (HWS)), and three paired significant wave height and period cases. Stability is assessed using visual unit-state classification, percentage stability and damage, interlocking-induced stability gain, and a dimensionless stability number framework. The results show that interlocking units consistently improves stability, particularly under high-wave and low-water conditions. Under the LWS in the highest wave case, the interlocking arrays retain 50.0 - 86.4 % stability, whereas the non-interlocking arrays decrease to 20.0 - 53.0 %. The 731-GR (seven-base pointy-side) group configuration shows the most robust response among the tested layouts, whereas the 631-SL (six-base flat-side) single configuration is the most vulnerable. These findings indicate that, under the tested laboratory conditions, interlocking acts not only as a geometric modification but also as a collective stability mechanism that preserves array compactness and delays unit mobilization. This study provides a stability-oriented experimental basis for designing the placement of modular submerged artificial reefs for coastal protection.
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Cite this article:
APA Style:
Armono, H. D., Suwardi, Satrio, D., Wahyudi, & Luthfi, A. Q. (2027). Hydraulic stability of interlocking modular hexagonal artificial reefs under varying water levels. Maritime Technology and Research, 9(1), 289775. https://doi.org/10.33175/mtr.2027.289775
MDPI Style:
Armono, H. D.; Suwardi; Satrio, D.; Wahyudi; Luthfi, A. Q. Hydraulic stability of interlocking modular hexagonal artificial reefs under varying water levels. Marit. Technol. Res. 2027, 9, 289775. https://doi.org/10.33175/mtr.2027.289775
Vancouver Style:
Armono HD, Suwardi, Satrio D, Wahyudi, Luthfi AQ. (2027). Hydraulic stability of interlocking modular hexagonal artificial reefs under varying water levels. Marit. Technol. Res. 9(1):289775. https://doi.org/10.33175/mtr.2027.289775
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Highlights
- Non-interlocking and new interlocking hexagonal reef modules were tested in a wave flume.
- The LWS with high waves produced the worst stability of hexagonal reef modules.
- Stability was configuration-dependent; 731-GR was most stable and 631-SL least stable.
- Interlocking units enhanced system resistance by maintaining compactness and limiting motion.
- Crown locks restricted movement and maintained stability of the multilayer reef.
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