Title: Physical and Mechanical Properties of Mortars Containing Incinerated Sludge Ash and Silica Fume
Author(s): Anant Parghi and M. Shahria Alam
Publication: Symposium Paper
Appears on pages(s): 1-30
Keywords: Sludge ash; silica fume; Portland cement; mortars; setting time; water absorption; sorptivity; compressive strength; flexural strength.
The aim of this study is to investigate the physical and mechanical properties of cement mortar by replacing a portion of cement with incinerated sludge ash (SA) and silica fume (SF) at different proportions. The experimental program consists of four series. In series-A, the substitution amounts include 0%, 5%, 7.5%, 10%, 12.5% and 15% of SA. In addition, in series A, B, C and D of the experimental program, 0%, 10% 15% and 20% of SF were added, respectively. The tests performed include consistency, setting time, flow table spread value, flexural strength (Rf), compressive strength (Sc), apparent bulk density, water absorption and sorptivity. The results show that the initial and the final setting times and workability increased, when the percentage of SA was higher. Due to little pozzolanic
reaction, the strength activity index (SAI), and the initial compressive and flexural strengths of SA mortar decreased.
However, addition of SF to SA mortar could improve its mechanical properties. Statistical analysis is also conducted
to forecast the flexural and compressive strengths of mortar, and an equation is proposed by performing regression analysis.