Building damage from expansive steel slag backfill

Expanding steel slag backfill was unexpectedly found to be the cause of vertical movements of the floor of a basementless building that resulted in significant damage to window and door frames. Five years after construction some parts of the building were still heaving at a rate of 1 cm per yr. Swelling properties of the slag when exposed to different conditions of temperature and humidity are reported. Characteristics of iron blast furnace and steel open hearth furnace slags are described and on this basis it is advocated that only blast furnace slags be used in cases where long-term volume changes cannot be tolerated. Use of other slags in such circumstances should be prohibited unless accompanied by specific evidence that they will not expand.Le remblayage de scories d'acier expansives a \ue9t\ue9 trouv\ue9 d' une facon inattendue comme \ue9tant la cause de soul\ue8vement du plancher d'un \ue9difice sans cave. Cette situation causa des dommages importants aux cadres des portes et fen\ueatres. Cinq ans apr\ue8s la construction, certaines parties du b\ue2timent \ue9 taient encore soulev\ue9es au rythme de 1 cm par ann\ue9e. Les propri\ue9t\ue9s de gonflement de la scorie, une fois expos\ue9e aux diverses conditions de la temp\ue9rature et de l'humidit\ue9 sont expliqu\ue9es. Les caract\ue9ristiques des scories de haut- fourneaux sont d\ue9crites et, sur cette base, on sugg\ue8re de n' utiliser que les scories des haut-fourneaux dont le changement de volume \ue0 long terme peut \ueatre tol\ue9r\ue9. L'usage d'autres scories en de telles circonstances devrait \ueatre prohib\ue9 a moins qu'il puisse \ueatre \ue9tabli qu'elles auront un volume stable.Peer reviewed: NoNRC publication: Ye