In the present work, the interlocking blocks was modified by partial substitution of lateritic soil
(LS) with bagasse ash (BA). The effect of ordinary Portland cement (OPC) to LS ratio of 1:3 1:5
1:7, 1:9 and 10, 15 and 20 wt.% of BA content on the engineering properties of interlocking blocks
was investigated. The chemical and physical properties of LS and BA were determined by X-ray
fluorescence spectrometer, sieve analyzer, and scanning electron microscope. The engineering
properties of modified interlocking blocks were compared with interlocking blocks without
replacement of BA. The results show that BA was a porous material with high water adsorption.
The adding BA to interlocking blocks decreased compressive strength, dry density values and lead
to high void within interlocking blocks structure. The interlocking blocks at OPC:LS ratio of 1:5
with 15 wt.% of BA were perfectly suitable for inside and outside building construction.