Alkali–silica reaction damage to Elgeseter Bridge, Trondheim, Norway: a review of construction, research and repair up to 2003

Abstract Elgeseter Bridge was built in the period 1949 to 1951 and is a unique design for Norwegian construction in this era. In the early 1990s, deleterious Alkali–Silica Reaction (ASR) was investigated and explains the observed expansions and cracking of the concrete. Damage due to ASR has occurred most severely on western face of the structural elements which are exposed to the elements in the middle of the river. In situ measurements since 1995 have provided important information on the relative humidity within the concrete and the rate of crack expansion. Relative humidity is generally high (100%) and cracks expand at a maximum rate of 0.15 mm per year. Column tests with impregnation of monosilane have given very promising results. One product with creamy consistency has reduced the relative humidity to less than 80% at a distance of 50 mm from the surface, and theoretically “stopped” or significantly reduced the ASR.