Passing a direct current through a jointed fine grained soft rock mass
auses the movement of water by the process of electric-osmosis. There
are other processes such as electrolysis which transport ions that interact
with associated ions and can, in turn, be oxidised. This results in the
dissolution products being transported towards the cathode electrode. In
the cathode region the ferrous hydroxide is oxidised to ferric hydroxide
%%ith consequent precipitation. The cracks and joints are current
pathways, along which the ferric hydroxide is deposited. This deposition
reinforces the joints and increases the shear strength. By adding calcium
chloride to the anode, the rate of corrosion is increased with the
concomitant increase of deposited ferric hydroxide along the joints. This,
in turn, significantly increases the joint shear strength. The process is
pervasive in that the current via the water paths travels through the crack
and joint systems The result is that not only specific joints are reinforced
but the cracks and mtciconnected voids are also reinforced.