The detrimental power of alkali silica reaction: remarkable case study

Author(s): G. D. Schutter (Invited speaker)
Paper category: Proceedings
Book title: Proceedings of the Seventh International Conference on Concrete under Severe Conditions – Environment and Loading
Editor(s): Z.J. Li, W. Sun, C.W. Miao, K.Sakai, O.E. Gjørv, N.Banthia
ISBN: 978-2-35158-124-7
e-ISBN: 978-2-35158-134-6
Publisher: RILEM Publications SARL
Publication year: 2013
Pages: 314-327
Total Pages: 14
Language : English

Abstract: Since the 1980’s, alkali silica reaction (ASR) has become widely known as a major damage mechanism for concrete structures. Although some discussions remain about the details of the chemical reaction process and the expansive damage mechanism, many standards and prescriptions nowadays include some practical rules in order to avoid the occurrence of ASR in new concrete structures. The better understanding of ASR and the definition of the practical rules have led to a significant reduction in number of ASR damage cases worldwide. ASR is now more considered to be an important issue for existing older structures. However, in spite of the better understanding of ASR and the existence of practical rules, ASR sometimes still occurs in new concrete structures. This papers shows the remarkable case of concrete columns within a frame supporting a crane bridge, in open air. Severe damage due to ASR occurred within less than five years after construction. At the top of the columns, concrete spalled off, yielding a risk on injuries for the technicians operating the bridge. The concrete contained limestone aggregates from Tournai in Belgium, and was made with ordinary Portland cement. In spite of the good concrete quality, severe ASR expansion rapidly occurred in the columns in open air, exposed to rain. Identical columns positioned in the construction hall, protected from rain, also show damage features caused by ASR, although much less pronounced. This illustrates the important role of moisture on the ASR expansion rate. Because of the extremely detrimental nature of ASR in this case of the columns in open air, it was decided to demolish and reconstruct.

Online publication : 2013
Publication type : full_text
Public price (Euros) : 0.00