Self-Consolidating
Concrete - Form Pressure Research Update
March 18, 2008
The 3rd Progress Report on SCC Formwork Pressure research is now available to SDC members. This report represents completion of 75% of the research project begun 18 months ago by the team of Kamal Khayat (University of Sherbrooke), Surendra Shah (Northwestern University), David Bonen (Consultant), and Jerzy Zemajtis/Peter Taylor
(CTLGroup).
The research project seeks a better prediction of pressures in formwork induced by the placement of self-consolidating concrete. At this time, the recommendation in ACI 347-04 “Guide to Formwork for Concrete” is that such lateral pressures during concrete placemen for concrete with slumps in excess of 7 inches should be assumed to be the full fluid pressure of concrete. This presents a difficult financial and practical barrier to the use of SCC in vertical construction, requiring stronger formwork and potentially limiting the lift height of vertical placements.
As noted, the research seeks to provide a more definitive lateral pressure based on mixture design and placement speed, as well as a mechanism for field testing to confirm such pressure. Full scale tests are included as part of the research program.
Funding for this $385,000 research project was provided by the Strategic Development Council (40%) and the RMC Research & Education Foundation (60%). A special thanks to SDC contributors:
Axim Italcementi Group
Baker Concrete Construction, Inc
BASF Construction Chemicals, LLC
Doka USA, Ltd
The Euclid Chemical Company
Handy Chemicals, Ltd
Sika Corporation
W.R. Grace & Co
For more information on self-consolidating, refer to ACI 237R-07 - Self-Consolidating Concrete. |