CATHODIC ANTI-CORROSION APPARATUS, NAMELY, EQUIPMENT BASED ON CARBON FIBRE NETTING INTENDED FOR CATHODIC PROTECTION OF CONCRETE CONSTRUCTIONS; ELECTROCHEMICAL CHLORIDE EXTRACTION AND REALKALISATION IN REINFORCED CONCRETE OR SIMILAR MATERIAL; CRACK PREVENTION IN CONCRETE CONSISTING OF A MAT OF OPTIONAL COATED CONDUCTIVE CARBON FIBRES