Impact of pH Water and Mineralogical Microstructure of Soil Mixed with Wood Waste on the Compressive Strength of Composite Bricks; and Bricks Resistance Modeling

摘要

This study includes the manufacture of cement stabilizedclay bricks with embedded mahogany chips. The impact of this waste and its interactionwith water in the bricks was evaluated on the mechanical properties. The compressivestrength tests using a universal press were carried out on bricks with and withoutadding wood chips. The results obtained show that the incorporation of wood chipsinto the bricks decreases the compressive strength. This reduction in compressivestrength led us to conduct an analysis of clay and water as intrinsic factors, beforeand after incorporation of untreated woodwaste. Thus, a mineralogical analysis of theclay with and without mahogany chips was made using an X-ray diffractometer, usingan anticathode of cobalt with the line Κα, of wavelength λ = 1789Å. After quantification of the mineral constituents, it is noted that theconcentration of SiO2 decreases considerably in the clay with addition of wood chips, resulting in the reductionof the compressive strength in these composite materials (from Rc = 9.26 MPa at0% of chips to 3.55 MPa at 8%). A mathematical modelfollowing the interpolations of Lagrange was then proposed. The analysis of thewater resulting from the impregnation of dry wood chips in the water, shows thatthe water becomes strongly acid (pH = 4.3 at the 7th day of immersion), thus contributingto the reduction of resistance. This analysis of intrinsic factors will allow futurestudies to take into account the treatment of wood waste by different processesin order to increase the mechanical, thermal and acoustic properties of compositebricks with the same contents, thus generating massive support for the use of itscomposite materials.