ICELANDIC-TYPE BERM BREAKWATER: COASTAL STRUCTURE WITH A LOW- CONSTRUCTION CARBON FOOTPRINT

Various types of rubble mound structures are used to protect ports and coasts. The construction of these structures has a significant carbon footprint. With an urgency to address climate change, there is growing interest in exploring and using more environmentally friendly coastal structures. In addition to engineering and cost factors, the construction Global Warming Potential (GWP) is an important factor in the selection and design of the structures. Indeed, knowledge of construction GWP supports decision-making in coastal projects to achieve climate goals. Considering the widespread construction of Icelandic-type berm breakwaters (IceBB) worldwide, this structure’s design method is commonly accepted in coastal projects. The design method is aimed at maximizing the quarry’s utilization and matching the structure's rock gradings with the predicted quarry yield. This eliminates the need for reinforcement of the structure by concrete armor units and thus reduces the GWP associated with breakwater construction. In this study, the construction process GWP of IceBB is assessed and compared with a conventional rubble mound breakwater with Cubipod concrete armor units (ConRMB). The Life Cycle Assessment (LCA) method is applied to calculate the construction carbon footprint of the structures. The GaBi software is used for the LCA in this study. The assessments and comparisons are made for different scenarios in two Icelandic port projects, namely, the port of Thorlakshofn project and the port of Straumsvik project. The results indicate that IceBB has a significantly lower GWP compared to ConRMB with Cubipod concrete armor units. The findings support decision-making in coastal protection projects for adopting the IceBB design method aimed at meeting climate change mitigating policies.