Sawdust ash as concrete material

Some properties of concrete with sawdust ash (SDA) as a replacement for ordinary portland cement (OPC) are investigated. The compressive strength of specimens with replacement levels ranging from 10 to 30% cured for periods of 3-90 days showed a decreasing strength with higher ash content. The 28-day split tensile strength of SDA concrete specimens showed a similar trend. The SDA concrete was observed to gain rapid strength at later ages, indicating a pozzolanic activity of the ash. Although only concrete with a 10% replacement level attained the 20 N/mm2 designed strength at 28 days, test results indicate that SDA concrete can attain the same order of strength as conventional concrete at longer curing periods.