The eco-slabs have been constructed using moulds and are made of various types of concrete. They were attached to one of the breakwaters (Zuiderhavenpier) of IJmuiden harbour in April 2008. The breakwater consists of concrete blocks of 22 and 30 metric ton embedded in asphalt.
In total, 20 slabs have been placed from low water to high water mark: 10 were placed in wave exposed locations and 10 at sheltered locations. The aim of this variation is to determine the optimum position for the various textures with respect to water level. The slabs were placed using a crane and mounted to the concrete blocks using bolts and nuts.
The additional costs for the production of eco-concrete is only marginal with respect to the costs of ‘smooth’ concrete blocks.