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 ACCROPODETM 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.