Ash from timber waste as cement replacement material

Sawdust is a waste product from the timber industry. Research work carried out on the ash derived from the sawdust has confirmed its pozzolanic properties with a pozzolanic index value of 75.9%. This material compares favourably with fly ash and wastes from the oil palm industry. The only difference noticed is in the low content of Al2O3 (4.09%) and Fe2O3 (2.26%). Concrete mixes have been proportioned to have various percentages of cement replacement with sawdust ash (SDA) ranging from 0% to 30% by mass. Performance of the ash-portland cement mixture has been evaluated with respect to setting time, workability and compressive strength. From the results obtained, 10% replacement of cement with SDA shows good performance giving the desired workability and strength. (C) 2002 Published by Elsevier Science Ltd.