OasisLMS

Given the high flowability and relatively fast casting rate of self-consolidating concrete (SCC), such concrete can exert high form pressure. Accurate assessment of form pressure is necessary from a safety and economic points of view. The maximum form pressure and pressure decay are dependent on the structural build-up of the concrete at rest following placement, as well as placement parameters. The objective of this course is to present information on the key parameters (including constituent materials, mixture proportioning, and casting parameters, such as the casting rate, concrete temperature, concrete element shape and size, and reinforcement density) affecting thixotropy and SCC form pressure. Prediction models available for estimating SCC form pressure are also presented.

The contents of this course include six recorded presentations from the ACI 2021 Spring Virtual Convention.
• Thixotropy and Form Pressure Exerted by SCC, by Kamal Khayat, Missouri University of Science and Technology
• Effect of Materials and Mixture Composition of SCC on Form Pressure, by Kavya Vallurupalli, University of Missouri Rolla
• Methods of Monitoring In-situ Form Pressure and Interpreting the Results, by Mitchell Matias, EllisDon Corporation
• Field Validation of Formwork Pressure Prediction Models, by Lorena Proietti, EllisDon Corporation
• Prediction Models for SCC Form Pressure, by Ahmed Omran, New Jersey Institute of Technology & Massachusetts
• Consultants Experience with Assisting Contractors with Formwork Pressure, by Benjamin Birch, CTLGroup

1. Describe the role of concrete rheological properties (structural build-up at rest) on form pressure exerted by SCC.
2. Discuss various test methods to evaluate structural build-up at rest of SCC that can be used for mixture design and quality control on job site.
3. Recall various models that can be used to assess form pressure characteristics and key factors affecting maximum form pressure and pressure decay, including mixture constituents, mixture design, and placement parameters, such as casting rate and presence of reinforcing steel.
4. Recall form pressure tests results of self-consolidating concrete constructed same size elements using two different casting rates and how test results help strategize formwork design and casting rate decisions.

Study the materials included in this module. Then, complete and pass the corresponding 10-question quiz with a score of 80% or higher to receive a certificate for 0.2 CEU (2.0 PDH).
Continuing Education Credit: 0.2 CEU (2.0 PDH)
Approved by AIA and ICC
Access Period: 30 days