Substitution of limestone filler by waste brick powder in self-compacting mortars: Properties and durability

The feasibility of using waste brick powder (WBP) in the manufacture of self-compacting mortar has been investigated in this study. The limestone filler was partially or totally (0%, 50% and 100%) substituted with WBP. The rheological properties, compressive and flexural strengths, drying shrinkage and durability properties (including carbonation resistance, chloride ion diffusion and sulphate resistance) of self-compacting mortars were evaluated. The WBP-mortars presented a higher yield stress and plastic viscosity than that of WBP-free mortar: the additional water has to be added in order to achieve the equivalent workability. The compressive strength of WBPmortars slightly decreased after 7 days (the compressive strength of series mortars M - BP decreased 5.6% and 9.3% for 50% and 100% WBP based mortars comparing with the reference mortar, respectively; while the compressive strength of series with similar workability mortar M-BP100WA which was based on 100% WBP decreased 16.7% and it could achieve 26.8 MPa), but the decreasing trend seemed to be compensated by the pozzolanic activity of WBP and remained equivalent after 28 days (the compressive strength of series mortar MBP100WA decreased 5.3% and it could achieve 35.6 MPa). The substitution of limestone filler by WBP didn't seem to impair the durability behavior of mortars (except for the resistance to carbonation). Therefore, it is possible to manufacture self-compacting mortar by partially or totally substituting limestone filler by WBP.