Title: Norwegian Experience in the Use of Pozzolans to Reduce Chloride-Ion Intrusion

Author(s): J. Lindgard, O. Skjolsvold, and K. Kjellsen

Publication: Symposium Paper

Volume: 212

Issue:

Appears on pages(s): 721-736

Keywords: binder type; bridges; chloride intrusion; durability; pozzolans

DOI: 10.14359/12718

Date: 6/1/2003

Abstract:
Concrete structures on the western coast of Norway are exposed to a harsh environment, mainly wind and sea water. The concrete should be designed in order to sustain attach from the environment and especially reinforcement corrosion, which is the most serious type of damage on coastal concrete structures. Several major Norwegian research projects have taken place in order to improve durability by correlating relevant durability parameters to environmental exposure, material composition, structural geometry and details. The most important factors to resist deterioration are thickness of the concrete cover and the concrete composition. This paper reviews some of the results from these projects, and concentrates mainly on the binder type. Attention is paid to the addition of silica fume and use of a fly ash portland cement, introduced in Norway in the late 70's and early 80's, respectively. Laboratory testing (several methods), in-situ exposed specimens and long-term in situ experience clearly demonstrate the beneficial effect on the chloride-ion intrusion from the addition of pozzolans to the binder. The results have lead to improved practical recommendations and regulations concerning concrete composition for structures in Norway exposed to chloride-ions.