What is the impact force on formwork resulting from a shotcrete application? I am designing the formwork for a wall to be placed via shotcrete and need to know the forces imposed on the wall forms.

In structural applications, most of the impact force from nozzling shotcrete is directed toward compacting the shotcrete in place rather than against the formwork. This was the subject of a study conducted by Marc Jolin of Laval University, Quebec City, QC, Canada, and reported in the Fall 2007 issue of Shotcrete magazine. There is virtually no hydrostatic pressure on the forms from the application using the shotcrete process. A copy of this study can be viewed on the ASA Web site at www.shotcreteweb.wpengine.com/archivesearch/ArchiveSearch.asp.