PURPOSE: To increase prompt releasability, erosion and stability by saturating rockwool containing carbon entangled therein with a vinyl ester resin of a prescribed viscosity and adjusting the viscosity of the composition.

CONSTITUTION: Ores different in hardness are mixed and molten into rockwool, which is mixed with fibrous carbon. The mixture is saturated with a vinyl ester resin, polyester resin, epoxy resin, urethane resin, fluorine resin or urea resin of about 1,000cps and the viscosity is adjusted to 1,800 to 150,000cps to give FRP-reinforced binder. When needed, the binder is used in pavement, or to produce blocks for pavement such as plate blocks, interlockings or terrazzo, and blocks for water conduits such as underdrain, Hume concrete pipes, inlet traps, breast walls, interior or exterior walls for buildings and bases for buildings.