METHOD FOR MANUFACTURING A PRECAST COMPOSITE STEEL AND CONCRETE BEAM AND A PRECAST COMPOSITE STEEL AND CONCRETE BEAM MADE ACCORDING TO SAID METHOD

摘要

The invention is a method for the construction of a precast composite steel and concrete beam (1, 100) of the type comprising the following stages: the preparation of a single metal sheet (2, 102) extending mainly in the longitudinal sense; the creation of a plurality of through holes (3, 103) in the metal sheet (2, 102); the folding of the metal sheet (2, 102) to obtain an elongated shaped body (4, 104) with a substantially omega-shaped cross sectional profile; the arrangement of the open end (51, 151) of the concavity (5, 105) defined in the shaped body (4, 104) so that it faces upwards; the insertion inside the concavity (5, 105) of a plurality of rebars (6, 106) for concrete comprising longitudinal rods (61, 161); the insertion of a plurality of connecting elements (7, 107) inside the through holes (3, 103) made in the shaped body (4, 104); the casting of a concrete core (8, 108) inside the concavity (5, 105), the concrete core being completely in contact with the internal surfaces of the shaped body (4, 104), the internal surfaces defining the concavity (5, 105); the arrangement of the assembly made up of the shaped body (4, 104) and the concrete core (8, 108) so that the concavity of the shaped body (4, 104) faces downwards; the installation of the assembly made up of the shaped body (4, 104) and the concrete core (8, 108); the casting of concrete (9, 109) to complete work, in contact with at least the outer surface of the shaped body (4, 104) so as to complete the precast composite steel and concrete beam (1,100); the precast composite steel and concrete beam of the invention is constructed so that before concrete is cast in order to obtain a concrete core (8, 108) in the concavity (5, 105) a plurality of torsion resistant elements (11, 111) suited to resist the torsional stress of the precast composite steel and concrete beam (1, 100) is associated with the shaped body (4, 104).