Abstract:
Masonry units are usually joined using cement mortar. A good bond between the
bricks is essential and determines how the masonry units transfer and resist stresses
due to applied loads. In this study interlocking brickswere used to construct a wall
without the use of cement mortar. The aim of this study was to evaluate the effect
of different amounts of Municipal Solid Waste Ash (MSWA) on the strength
characteristics of the walls subjected to compressive loads. The soil used for making
the bricks was stabilized using MSWA applied at the rate of 0%, 2%, 5% and 10% of
the weight of soil. The compressive strength of individual soil bricks moulded in a
CINVA‐Ram machine was obtained during the curing period and samples were
tested on days 7, 14 and 28; after the start of the curing period. Walls, 840 mm high
and 1100 mm long, were constructed using the bricks after curing them for 28 days.
A compressive force was applied on the masonry walls in a direction normal to
joints. Addition of 2% MSWA gave the bricks the highest compressive strength on
Day 28. The failure pattern of the wall constructed using bricks stabilized with 2%
MSWA followed diagonal cracks and bulging of the wall from the sides. At failure the
wall had a maximum crack width of 40 mm and a vertical central deflection of 20
mm at failure. The ultimate stress of the stabilized wall was 2.47N/mm2 occurring at
a strain of 11. On the other hand un‐stabilized Juja soil masonry wall had a maximum
compressive stress of 2.5 N/mm2occurring at a strain of 9.5. The failure of the unstabilized
Juja soilbrickwall was mainly due to vertical cracks forming below the load
application point. For the un‐stabilized brick wall, the central deflection at
failurewas 14 mm, and was less than the deflection of the stabilized wall at failure.
This indicated that the stabilized brick wall was more ductile than the un‐stabilized
brick wall. Compared to the wall constructed using bricks stabilized with 2% MSWA
which had diagonal cracks, the un‐stabilized walls had nearly vertical cracks. The
failure of the stabilized brick wall was consistent with the provisions of the design
code BS 5628 Part 1 of the year 2005.
