Toward absolute durability performance criteria: preliminary case study of a sea lock

In order to achieve durable concrete structures, concrete code provisions typically require a minimum cement content, a maximum water cement ratio, and a minimum strength class. These ‘deemed-to-satisfy’ rules are mainly based on long-term practical experience. However, as there is a clear trend to use new binder types, considering alternative cement replacing and environment-friendly powders, this prescriptive approach can be criticized. Classical definitions such as cement content and water cement ratio are open to heavy debate in case of the alternative binder systems. Furthermore, the relation between durability performance of concrete based on new binder systems and the prescriptive parameters (cement content, water cement ratio, strength) is not without criticism either. The equivalent concrete performance concept (ECPC) offers a first step to a more soundly based evaluation of durability requirements for new binder types. Nevertheless, ECPC also has its limitations, as it is based on comparative testing still considering a deemed-to-satisfy reference concrete. A more fundamental solution can be based on absolute durability performance for the concrete to be applied in a structure. This performance can be checked in laboratory conditions (potential performance) as well as on the completed structure (as-built performance). In this study, some preliminary research results are reported in view of defining absolute durability criteria for a sea lock to be constructed.