Foundation

For the foundation, I would like to repave the existing pavement with a concrete that consist of 15% fly-ash.

"Fly ash is one of the residues generated in combustion, and comprises the fine particles that rise with the flue gases. Ash which does not rise is termed bottom ash. In an industrial context, fly ash usually refers to ash produced during combustion of coal. Fly ash is generally captured by electrostatic precipitators or other particle filtration equipment before the flue gases reach the chimneys of coal-fired power plants, and together with bottom ashremoved from the bottom of the furnace is in this case jointly known as coal ash. Depending upon the source and makeup of the coal being burned, the components of fly ash vary considerably, but all fly ash includes substantial amounts of silicon dioxide (SiO₂) (bothamorphous and crystalline) and calcium oxide (CaO), both being endemic ingredients in many coal-bearing rock strata."


Taken from Wikipedia:
http://en.wikipedia.org/wiki/Fly_ash