Behavior of self- compacting concrete incorporating calcined pyrophyllite as supplementary cementitious material

Abstract

The current trend of industrial concrete leans more towards the use of self-compacting concrete. These must have fresh properties well defined as fluidity, filling ability and resistance to segregation. However, to ensure the rheological stability, use mineral fines is required. In this work, powder of calcined pyrophyllite (CP) was used as cement substitution at level of 10% and 20% by weight. The interest is focused on the role played by the calcined pyrophyllite to produce SCC with reduced impact environmental.. Calcination of pyrophyllite powder was carried out at 750 °C. Its effect on the workability and mechanical properties of self-compacting concrete is analyzed. The results show that the properties of workability of SCC containing 10% of calcined pyrophyllite tested at fresh state (Slump Flow, T50, passing ability and segregation resistance) are almost identical to those of the control SCC. Furthermore, the calcined pyrophyllite increases the compressive strength, tensile and flexural strength of SCC approaching without exceeding those of the control SCC. It seems that 10 % of calcined pyrophyllite is the optimum replacement rate which improves mechanical strength compared to 20%. Replacing cement with the calcined pyrophyllite aims to save cement and reduce the CO2 emissions released during the manufacture of cement.

Rheological properties and mechanical strength of self-compacting mortars produced with marble powder and calcined clay

“…10%BC, 13%KT1 and 10% MP from 26 cm to 10 cm for binary mixes 50% GC, 50% BC, 70% KT1 and 10% MP. The observed decrease in slump flow is mainly due to the high water demand of calcined clays compared to cement (21,22). It is also reported that, with same w/c ratio, the decrease of fresh SCMo fluidity with the increase of CC may be due to their high specific surface area and irregular grains morphology (23).…”

Can we eat Earth Buildings? The mineralogical common of earth building and edible earth practices

“…Calcined pyrophyllite has been studied as a cement replacement and it was shown to increase the compressive, tensile, and flexural strength of self-compacted concretes (Mansour 2020).…”

Behaviour of Self-Compacting Concrete incorporating Natural Perlite used as Part of Cement and as Aggregates

“…When the perlite is used as cement substitution, PP10, PP15, and PP20 are homogeneous but less stable than PN0. This is due to the increase of the amount of perlite fines in SCC which facilitates the passage through the sieve and increases the milt weight [38].…”