There is need to provide alternative materials that are locally available, that can
reverse the adverse environmental effects caused by excessive use of Portland
cement. It is important to have materials with low energy demand and low cost.
The overall objective of this research was to assess the suitability of sisal fiber
reinforced cement mortar with termite clay soil partial replacement for cement for
use in roofing tile for housing. Termite Clay Soil (TCS) was obtained from Nduru
Village, Usigu Sub Location, Siaya County in Kenya. The TCS used in this
research was uncalcined. Chemical analysis on TCS was carried out by use of
Energy Dispersive X ray diffraction (EDXRD), which is an analytical technique
for characterizing materials. The sum of SiO2, Al2O3, and Fe2O3 was found to be
93%, which is greater than 70% required as stipulated by the ASTM C 618
(1980). The pH of TCS was determined using pH meter and found to be 5.21.
TCS replacement levels of 0, 10, 20, 30 and 40% by weight of cement was carried
out to determine setting times, compressive strength, flexural strength and
absorption rate of the resulting blended cement, from which optimal replacement
value was obtained. 10% optimal replacement level achieved was used to
determine the engineering properties of mortar namely compressive strength,
flexural strength and absorption with sisal fiber reinforcement (SFR) of 0, 0.5,
1.0, 1.5 and 2.0% by weight of cement and fiber length of 25mm. Other studies
have established that 25 mm length is optimal and this research adopted this
length without further studies. The optimal replacement level for TCS was found
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to be 10% for cement achieving compressive strength of 44.9 N/mm2
, flexural
strength of 6.5 N/mm2
and 6.5 % absorption rate which satisfied the requirement
of KS EAS 18-1:2001 of minimum of 42.5 N/mm2
for 42.5N Cement. Up to 2 %
sisal fiber reinforcement satisfied the requirement of KS 02-444: 1984 of
minimum 2.80 N/mm2
for flexural strength and maximum 10% for absorption
rate. Residual impact strength ratio (Irs) of sisal fiber reinforced cement mortar
with sisal fiber reinforcement for cement at percentages of 0, 0.5, 1.0, 1.5 and
2.0% increased with increase in reinforcement and at 2%, it yielded a value of
3.00. It was concluded that TCS was pozzolanic with the sum of SiO2, Al2O3 and
Fe2O3 equals to 93% and its pH was 5.21 which is acidic and therefore suitable
for reducing the alkalinity of the cement matrix and hence reduction in
embrittlement of sisal fibers. The optimal replacement of TCS was 10% for
cement with up to 2% sisal fiber reinforcement for use in roofing tiles. Since Irs is
closely related to Coefficient of restitution (CoR), this value satisfied the
requirement of BS EN 14411: 2012, which recommends a minimum value of 0.55
for tiles intended for floors with low mechanical requirements. No standard was
available that specifies the impact energy and impact residual strength ratio for
roofing tiles and therefore this research adopted the standard for floors. From the
cost analysis, cost per square meter of sisal fiber reinforced cement mortar with
termite clay soil partial replacement tile was found to be Ksh 240, which is
cheaper than other roofing materials which are in the range of 300 to Ksh 2000.
There are also associated benefits which include: reduction of alkalinity of the
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cement media and therefore preservation of sisal fibers in the matrix; reduction in
the emission of greenhouse gases by partial replacement of cement with the
pozzolanic material and low energy consumption. Further studies are
recommended on uncalcined termite clay soil as partial replacement for cement
for use in roofing tiles.