The Use of Sawdust and Palm kernel Shell as Substitute for Fine and Coarse Aggregates in Concrete Construction in Developing Countries

Abstract

This study examined the use of the locally available building materials such as
sawdust and palm kernel shell as possible substitutes for fine and coarse aggregate in concrete. The physical properties such as specific gravity, Bulk density, Absorption test and sieve analysis test of these local materials were examined. The materials were batched by volume for the production of concrete and slump test were done on concrete to compare and control the water content. Four sets of concrete were casted (cement: sawdust: granite, cement: sand: granite, cement: sand; palm kernel shell and cement: sawdust: palm kernel shell) into cubes of size 150 x 150 x 150 using a mix ratio 1:2: 4 and 1:3:6.The concrete cubes were cured by sprinkling method for different time duration (7, 14, 21, and 28 days). The compressive strength tests were carried on the concrete. Compressive strength result for 1:2:4 and 1:3:6 concrete mixes show an overall reduction in compressive strength in all the mixes containing sawdust and palm kernel shell as compared to normal concrete mix (cement: sand: gravel). Also, there was a progressive reduction
in compressive strength with age. Absorption test carried out showed that the rate of water absorbed by sawdust and palm kernel shells are higher compared to sand and gravel respectively. This indicates that the water absorption capacity in both sawdust and palm kernel shells would need to be modified in order to improve its compressive strength and durability. The quality of concrete with palmkernel shells can be improved by breaking into smaller sizes before using the palmkernel shell to produce a well graded sample of various sizes which in turn will help in proper interlock of the particles in concrete mass.