Recycled rubber for use in manufacture of building materials; recycled rubber for use in manufacture of concrete blocks; recycled rubber for use in construction materials; concrete blocks, concrete reinforced with synthetic fibres, concrete slabs, concrete articles for building walls, concrete articles for retaining slopes, concrete articles for stablishing slopes, concrete beams, concrete building panels, concrete cladding sheets, concrete coatings, concrete facing panels, concrete facing sheets, concrete flooring blocks, concrete formwork, concrete joints, concrete palisades, concrete paving elements, concrete pre-fabrications, concrete products for use in buildings, all included in class 19