TITLE:
Impact of pH Water and Mineralogical Microstructure of Soil Mixed with Wood Waste on the Compressive Strength of Composite Bricks; and Bricks Resistance Modeling
AUTHORS:
Gilbert Ganga, Narcisse Malanda, Diogène Pongui Ngoma, Timothée Nsongo, Michel Dzondo Gadet
KEYWORDS:
Clay Bricks, Mineralogical Analysis, Wood Chips, Compressive Strength, pH Water
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.10 No.1,
January
20,
2020
ABSTRACT: This study includes the manufacture of cement stabilized
clay bricks with embedded mahogany chips. The impact of this waste and its interaction
with water in the bricks was evaluated on the mechanical properties. The compressive
strength tests using a universal press were carried out on bricks with and without
adding wood chips. The results obtained show that the incorporation of wood chips
into the bricks decreases the compressive strength. This reduction in compressive
strength led us to conduct an analysis of clay and water as intrinsic factors, before
and after incorporation of untreated wood
waste. Thus, a mineralogical analysis of the
clay with and without mahogany chips was made using an X-ray diffractometer, using
an anticathode of cobalt with the line Κα, of wavelength λ = 1789Å. After quantification of the mineral constituents, it is noted that the
concentration of SiO2 decreases considerably in the clay with addition of wood chips, resulting in the reduction
of the compressive strength in these composite materials (from Rc = 9.26 MPa at
0% of chips to 3.55 MPa at 8%). A mathematical model
following the interpolations of Lagrange was then proposed. The analysis of the
water resulting from the impregnation of dry wood chips in the water, shows that
the water becomes strongly acid (pH = 4.3 at the 7th day of immersion), thus contributing
to the reduction of resistance. This analysis of intrinsic factors will allow future
studies to take into account the treatment of wood waste by different processes
in order to increase the mechanical, thermal and acoustic properties of composite
bricks with the same contents, thus generating massive support for the use of its
composite materials.