Abstract:
This experimental thesis was carried out to study the properties of hollow concrete blocks by partial
replacement of banana leaf ash seeking objectives studying the physio-chemical composition by using
Atomic Absorption spectrometry, and determine the percentage of Pozzolanic activity index of banana leaf
ash with cement at different times of grinding or milling (0hrs ,0.5hrs ,1hrs ,2hrs &3hrs) for use of the ash
as the addition in the cement, to determine the effect of banana leaves ashes on fresh and Mechanical
properties of hollow concrete blocks. To examine the effects of banana leaves ashes on microstructure and
durability tests and minimize the cost of the hollow concrete block by minimizing the usage of cement by
potential material. Hollow concrete block production need binding material cement and supplementary
cementious material as an alternative. The Banana leaf ash is an agricultural waste which has a potential
to replace one of the construction materials which is cement. In this Study, an alternative trial mix has been
made to test or determine the effect of BLA on compressive strength ,water absorption , density , acid and
sulfate attack chemical resistance tests of hollow concrete blocks.The test were conducted by partial
replacement of Dangote Ordinary Portland cement 42.5R and Portland pozzolana cement 32.5R with 0%,
5%, 10% 15% and 20% of banana leaf ash for Class “A”,”B” and “C” Hollow concrete blocks. The
Material characterizations were investigated using X-ray diffiractometer, Feriour transform infrared
spectrometry, and Scanning Electron Microscopy analysis methods. The results were analyzed using Origin
pro 8 and Excel software’s. The X-ray diffiractometer analysis showed that 5%, 10%, 15%, 20% banana
leaf ash with dangote ordinary Portland cement 42.5R and Portland pozzolana cement 32.5 R have more
or less close grain size and crystals size amount with that of 0%Banana lea ash replacement and shows
crystalline particles before reactions and amorphous particles after reaction has been made. The structural
morphology of Dangote cement samples in different percentage of banana leaf ash was observed by
scanning electron microscopy. From scanning electron microscopy analysis, of 0%, 5%, 10%, 15% and
20% banana leaf ash mix, the chemical reaction of ordinary Portland cement 42.5R and banana leaf ash
, Portland pozzolana 32.5R and Banana after reaction with (Ca (OH) 2) showed production of additional
Calcium silicate hydrate gel which positively improves the strength of the blocks along test ages. The density
of the blocks except class B were within the minimum requirements of Indian standards .Class B blocks has
results greater than standards which was because of increased compaction.Test results indicate that hollow
concrete blocks produced by partial replacement of cement achievies better in strength and durability value
than the standards. Hollow concrete blocks are also chemically acid and sulphate resistant absorbing less
moisture. The results of mechanical properties of Banana leaves ash blended hollow concrete blocks show
that replacing banana leaf ash up to 20 % ,improved durability and microstructure behavior of blocks
which results in better performance than the standards.The optimum replacement of cement with Banana
leaf ash was 20%.