The breaking load of a masonry block is governed by the
tensile crack which is dependent on the bonding between the
POFA, cement and aggregate. For compressive strength, it was
discussed in the previous section that a higher POFA replacement
was related to a weaker bonding in the masonry blocks due to
possible limitations in chemical constituent in cement. A similar
reasoning may also be applied here as the breaking load decreases
with the increase in POFA content. Cracks or failure for
breaking load happens at a location of weakest bond. Therefore,
the mixing process for masonry block production is very important
to ensure proper blending between the POFA, cement and
aggregate. Unbalanced spread of these materials will result in
weak spots which could lead to cracking and consequently, a
lower breaking load.