Single-Layer Breakwater Armouring: Feedback on the Accropodetm Technology From Site Experience

Abstract

The single-layer technique appeared at the beginning of the 1980s, with the ACCROPODE™ unit, and is thus entering its third decade. At the time, this solution was a real innovation, reducing the amount of concrete and steepening armour facing slopes, hence reducing the volume of materials required. After three decades in use and more than 200 projects to date, it was important to summarize the lessons learned during this period and to inspect (above and below water) some of these structures in order to assess their behaviour and particularly to confirm the validity of the unit placing rules. In addition to the aspects related to armour stability, the focus has been given to the colonization by marine life of the structures, including the bedding layers, toe berms, underlayer, armour units. The purpose of this paper is to share the experience gained throughout the inspections undertaken since 2010 on structures built more than 10 years ago. A large panel of structures has been inspected, of different ages and at various locations worldwide.

How to Improve the Bioreceptivity of Concrete Infrastructure Used in Marine Ecosystems? Literature Review for Mechanisms, Key Factors, and Colonization Effects

“…Several studies have reported that the environment has a strong impact on the colonization of cementitious materials in the marine context (Giraudel, Garcia, and Ledoux, 2014; Lors, Feugeas, and Tribollet, 2019; Souche et al ., 2019). The medium influences the development and growth of microorganisms as well as the aging of the material.…”

“…Artificial marine structures modify, positively or negatively, the natural environment (Azevedo et al ., 2006) to become part of a new ecosystem (Giraudel, Garcia, and Ledoux, 2014). Then to avoid high negatives impacts, as frequently seen, the ecological mechanism of settlement on concrete needs to be assessed before their implementation (Baine, 2001; Bulleri and Chapman, 2010).…”

“…Then to avoid high negatives impacts, as frequently seen, the ecological mechanism of settlement on concrete needs to be assessed before their implementation (Baine, 2001; Bulleri and Chapman, 2010). Impacts parameters are divided in five main fields: localization for the immersion zone, implantation (Giraudel, Garcia, and Ledoux, 2014), seasons and immersion time (Firth et al ., 2014; Vaz-Pinto et al ., 2014), design of the structure (Baine, 2001; Pioch et al ., 2011), and the type of materials used (Anderson and Underwood, 1994; Fitzhardinge and Bailey-Brock, 1989; Lee et al ., 2008). There are also interdependent relationships that change over time between the type of structure, exposure conditions, substrate, seasonality, and colonization by living organisms (Anderson and Underwood, 1994; Choi, Ohno, and Sohn, 2006; Somsueb, Ohno, and Kimura, 2001).…”

L’écoconception maritime : une révolution pour les maitres d’ouvrages

“…Soulignons qu'il s'agit d'une démarche de restauration écologique et non d'une artificialisation des milieux naturels qui viserait la création d'une nouvelle "nature", aux fonctionnalités écologiques non préexistante, ni viable en dehors de toute intervention humaine d'entretien. Il s'agit pour cela de connaitre les processus naturels de colonisation par des organismes vivants marins, sur des types d'habitats naturels comme sur des ouvrages artificiels (GIRAUDEL et al, 2014). Il devient dès lors prioritaire, dans un double objectif de protection de l'environnement et de l'ouvrage, de comprendre également les mécanismes de peuplement qui pourraient altérer ou protéger l'ouvrage mais également le vivant qui le colonise (BAINE, 2001 ;AZEVEDO et al, 2006 ;BULLERI & CHAPMAN, 2010 ;SOUCHE et al, 2016).…”