A method of manufacturing a pre-stressed beam or panel and the resulting beam or panel are described. The method includes providing a timber-based component (1); providing a pre-stressing member (9) arranged along the timber-based component; applying a tensile force to the pre-stressing member (9); providing concrete anchors (11a, 11b) at locations that are spaced apart along the timber-based component (1); coupling the pre-stressing member (9) to the concrete anchors (11a, 11b); and releasing the tensile force on the pre-stressing member (9) to transfer a compressive force to the timber-based component (1) through the concrete anchors (11a, 11b) to form a pre-stressed beam or panel.

A precast concrete beam including a substantially planar web extending longitudinally between ends of the beam; a pair of flanges formed integrally with the web, each flange extending laterally from an elongate edge of the web and extending longitudinally between the ends of the beam so as to define a structure engaging surface of the beam; and a plurality of diaphragms formed integrally with the web and the flanges, each diaphragm spanning laterally between a side of the web and one of the flanges, wherein the diaphragms are spaced apart along the beam to thereby support the flanges.

A precast concrete beam including a substantially planar web extending longitudinally between ends of the beam; a pair of flanges formed integrally with the web, each flange extending laterally from an elongate edge of the web and extending longitudinally between the ends of the beam so as to define a structure engaging surface of the beam; and a plurality of diaphragms formed integrally with the web and the flanges, each diaphragm spanning laterally between a side of the web and one of the flanges, wherein the diaphragms are spaced apart along the beam to thereby support the flanges.

To provide a prestressed concrete which can be used for non-primary structural members such as general building members by using a chemical stress induced by an expansive material and a mechanical stress induced by a rust-resistant wire together and achieving reduction in weight and suppression of cracking. A prestressed concrete for non-primary structural members is characterized in that a mechanical stress induced by a tensional material and a chemical stress induced by an expansive material for a concrete are introduced and that the tensional material is a rust-resistant continuous fiber reinforcing wire.

There is a truss structure, assembly and method of manufacturing a truss with a span L and a beam depth H. The truss having a main part includes a substantially planar top chord with a longitudinal centerline and webs connecting between the top chord and a bottom chord. The top chord is separated from the bottom chord by the webs. There is a top chord node where each web intersects with the centerline of the top chord and a bottom chord node where each web meets the bottom chord. At least two of the top chord nodes coincide with one another along the top chord. In use, the elements of the main part are in compression and the bottom chord includes a tension member.