Research and Development towards Durable Advanced Concrete Structures

Abstract

Abstract The immense challenges related to the physical environment in the Arctic, calls for research within several areas. This paper discusses recent research taken on by Kvaerner, together with cooperation partners within the industry as well as universities and research institutions, to further improve the robustness and durability of concrete substructures used for offshore arctic applications. Some of the challenges addressed in the research are; Ice abrasion. Drifting ice in large concentrations and at large speed may abrade the exposed part of the structures if appropriate measures are not taken. Criteria and test methods are areas that are not properly addressed in any standards. Test methods need to correspond to actual exposure condition. Freeze-thaw resistance: Freezing and thawing cycles during the operational lifetime impacts the strength and the durability of a structure. Criteria and reliable test methods for structures exposed for extreme temperatures are not properly addressed in common test methods. A recently started research program at the Norwegian Technical University NTNU (2015) focus on these challenges to further improve acceptance criteria and test methods in order to obtain the planned service life for offshore platforms in the Arctic. The paper outlines the planned research for the coming years and how this can improve criteria and test methods to ensure that the design solutions selected for the sub-arctic platforms are able to resist the designs loads in these harsh environment. Early results from ongoing research programs are presented that show that improved understanding of the impact of the ice conditions and the resulting load on the concrete structure can enable a more reliable design and a more predictable service life. Representative acceptance criteria and test methods as part of the material qualification process are needed to ensure a reliable design. Improved understanding of the impact of ice in combination with low temperatures and temperature cycles may have a significant cost saving potential, and will ensure that the planned service life is met.