A mold board construction includes a body made of concrete and a number of steel wires embedded in the body. A number of grooves are formed in the surfaces of the body so that a number of protrusions are formed on the body, and a number of holes are formed in the body so that the body can be fixed to the strips. A number of mold board constructions form a hollow space for receiving an amount of concrete so that an object is formed. The mold board constructions form part of the object.