Abstract: According to the invention, a coupling device for a force transmitting member is provided. The coupling device contains a plurality of force transmitting members and a joint for coupling each end of the force transmitting members. A hardened body of a cement composition having a compressive modulus of elasticity of not less than 2.0.times.10.sup.5 kg/cm.sup.2 and a compressive strength of not less than 700 kg/cm.sup.2 is being filled at least in-between the force transmitting members and the joint.

Abstract: A process for manufacturing a precast composite structure of a matrix of cured carbon fiber reinforced concrete and at least one ferrous metallic member at least partly buried in said matrix, by forming an insulating layer of an electric resistance of at least about 100 ohms at least on that surface of the ferrous metallic member, which will otherwise be brought in contact with a concrete mix, placing the metallic member in position in a mold, pouring into the mold a concrete mix containing 0.2 to 10% by volume of carbon fiber so that said metallic member may be at least partly buried in said concrete mix, partly curing the structure until it becomes self-supporting, de-molding the partly cured structure, and fully curing the structure in an autoclave at a temperature between 100.degree. C. and 215.degree. C.