The Tremie Guide – About Concrete Performance and Sustainability

When far more than 50 years ago the first standards on concrete and tremie concrete have been written concrete technology was quite simple. Modern concrete is much more complex, which would allow to rate it also “high-performance” concrete. To specify the necessary criteria that are essential for a successful placement of concrete under submerged conditions in today’s foundations, which may exceed depths of 100 m, is a challenge. A joint task group of EFFC and DFI (European Federation of Foundation Contractors and Deep Foundation Institute) have brought together experts from the industry but also from consultants to find a common understanding on related topics. The group is presently updating the 2nd edition of the Guide to Tremie Guide for Deep Foundations, and edition 3 shall be released by end of 2024. It will also highlight the need for sustainability, to which the Tremie Guide contributes with its performance-based concept to design concrete, giving all options to materialize a low-carbon concrete without diminishing quality aspects. Future approaches may be founded on lessons learned from numerical modelling which is a key to better understand the complex interactions governing concrete flow mechanisms. The Task Group continues its work to validate simulations to justify new requirements, e.g. regarding a reduced workability retention for long-hours concrete placement. Eventually, revised regulations to concrete shall merge in relevant, contractually binding norms to make them broadly applied in practice, for a higher reliability in quality and for optimising sustainability of the construction.