Study of particle packing and paste rheology in alkali activated mixtures to meet the rheology demands of 3D concrete printing

Research output: Contribution to journalResearch articleContributedpeer-review


  • Sai Kala Kondepudi - , Chair of Construction Materials (First author)
  • Subramaniam Kolluru - , Indian Institute of Technology Hyderabad (Second author)
  • Behzad Nematollahi - (Joint last author)
  • Shin Hau Bong - (Author)
  • Jay Sanjayan - (Last author)
  • Swinburne University of Technology


The rheological behavior of concrete mixtures made with alkali-activated fly ash-slag (AAFS) binder paste is investigated for varying aggregate content. The static yield stress, plastic viscosity and thixotropy of the mixtures are evaluated and related with the performance in 3D Concrete Printing (3DCP). The thixotropy of the concrete mixture is primarily influenced by AAFS binder paste composition and does not change with the aggregate content. Rheology control of the AAFS binder paste is achieved using additives like nano-clay, which enhance the buildup of internal structure and provide thixotropy in the concrete mixtures. The paste content, the surface area of aggregate, and the packing of solids in a concrete mixture influence its yield stress. The static yield stress increases sensitively in relation to the proportion of the surface area of the solids to the paste volume content in the concrete mixture. The minimum requirement of the paste content from packing of solids in the mixture is given by the Fuller-Thompson curve. Excess paste content in proportion to the demand determined from the surface area of aggregate and packing of solids in the concrete mixture produces a decrease in the static yield stress. For producing AAFS concrete mixtures suitable for 3DCP, the paste content in the concrete mixture should meet the requirement of paste demand, which depends on the aggregate content and packing of solids.


Original languageEnglish
Article number104581
JournalCement and Concrete Composites
Issue number131
Publication statusPublished - Aug 2022

External IDs

Scopus 85130614080
WOS 000809714600001
Mendeley 468de407-2b4c-3aa1-8d4c-22d99cb4bbd9
unpaywall 10.1016/j.cemconcomp.2022.104581


Research priority areas of TU Dresden

DFG Classification of Subject Areas according to Review Boards

Subject groups, research areas, subject areas according to Destatis


  • 3D concrete printing, Aggregate packing, Geopolymer, Paste content, Rheology, Surface area

Library keywords