Technical Committee 305-PCC
General Information
Deputy Chair: Prof. Dr. Ir. Geert DE SCHUTTER
Cluster A
Subject matter
The main purpose of this new TC is to create a State-of-the-art report on pumping of concrete, incorporating the developments made in the last 20 years. Current international documents are substantially aged and need modifications to incorporate the results on modern concrete mixtures. The following topics are intended to be included:
- Behavior of concrete in pipes, including the formation, composition and properties of the lubrication layer
- Mechanisms of blocking, and including the influence of thixotropy
- Preparation of pumping pipes before pumping
- Test methods to characterize the lubrication layer properties
- Monitoring equipment during pumping (P, Q, velocities, …)
- Revising full-scale pumping tests and instrumented industrial projects
- Pumping prediction models and validations
- Revision of current pumping pressure prediction nomograms
- Methodologies to reduce pumping pressure
- Changes in concrete properties induced by pumping
- Applicability of numerical simulations to pumping behavior
- Influence of bends and reducers
Shotcreting and digital fabrication are not intended to be included in this TC.
Terms of reference
- The TC is anticipated to start at the RILEM Spring Convention in 2022 and is intended to take five full years.
- Membership: Potential members are located in Europe (Germany, Belgium, France, etc.), Asia (China, Korea, Arabian peninsula) and North-America (Canada, USA), based on the location of the majority of the research performed over the last two decades. The main composition of the group will be academic, but efforts will be conducted to include the industry, in terms of pump producers, material suppliers, contractors and companies producing testing equipment.
- The target of the TC is to perform bibliographical research. A document with recommendations or best practices can also be envisioned, dependent on the progress rate of the TC.
- The work of the TC can generate a report and recommendations similar to the ACI-304 and ACI-211.9 documents, intended to inform the industry on how pumping pressure can be predicted or altered (304) or on how to modify the mix design to make concrete pumpable (211.9).
Detailed working programme
The main goal of the committee is the STAR report, for which a first draft is anticipated to be ready in 2025. Based on the STAR, the recommendations could be created in 2026.
A joint session with ACI 304, 211 and 238 (workability) can be requested for the ACI Spring Convention in New Orleans, LA. A workshop could also be organized in Europe near the closure of the committee
Technical environment
The most appropriate cluster would be cluster A: Material Processing and Characterization. The TC will show overlap with multiple ACI technical committees, among which ACI 304 (mixing, measurement, transport and placement), ACI 211 (proportioning) and ACI 238 (workability). This TC is endorsed by RILEM TC 266-MRP, and will show minor overlap with the new 3D printing committee QPC.
Expected achievements
The main deliverable of this TC will be the STAR, followed by recommendations and best practices for industry. The recommendations and best-practices will mainly focus on pressure prediction models revising the old nomograms, and strategies to reduce pumping pressure.
The session at the joint RILEM meeting and ACI Convention in the Spring 2024 will have several presentations from academia and industry dealing with the proposed activities of the TC. In addition, we hope that this TC can further strengthen the collaboration between RILEM and ACI. The workshop at the end of this TC life will focus on the dissemination of the results, and on the best-practices and recommendations.
Group of users
The outcomes of this TC are targeted towards two groups of users: industry and academia, as explained in the next point.
Specific use of the results
The usefulness towards the industry would be to provide a comprehensive document including the major changes in pumping of concrete based on the results from the last two decades. To the knowledge of the proposers, there is no such document available which includes the latest developments. The current documents are outdated and contain information which is not always applicable to more modern concrete. With the further development of specialty, flowable and high-performance concrete, this knowledge is crucial to be spread to the industry to maintain the competitive advantage of concrete in the construction industry.
Towards academia, the STAR would provide an extensive summary on the work performed, replacing the current low number of review papers on certain aspects of this topic. This will make academics more aware of the literature available, giving new members in this field a better starting point to study the literature.
