June 7-10, 2009
Rebound is a significant factor when evaluating the quality and performance of a construction site using shotcrete. Rebound modifies the characteristics of shotcrete and must be disposed of. Thus a reduction in rebound becomes both a technical and a commercial objective.
Based on many years of experience with polymers in mortar applications, different polymer modified systems were developed for shotcrete applications and investigated in extensive full size trials. The investigations fully confirmed expectations as regards a reduction in rebound. At the same time the recently developed polymer has a retardant effect, giving the concrete other improved properties. Parallel to the technical investigations, the commercial aspects of this polymer on the use of shotcrete were examined. The properties of the additional polymer on shotcrete meet the high performance levels required by the J2 curve.
Erik Iglesias Dr.-Ing., TU Volker Wetzig Dipl.-Ing., Jürgen Bezler, and Mareike Xia Dipl.-Ing., "TECHNICAL AND COMMERCIAL EVALUATION OF MODIFIED SHOTCRETE IN TUNNEL CONSTRUCTION" in "Shotcrete for Underground Support XI", Felix Amberg, M.o.S. ETHZ, SIA, Switzerland; Knut F Garshol, BASF Construction Chemicals, LLF, USA Eds, ECI Symposium Series, (2009). http://dc.engconfintl.org/shotcrete/15