Concrete lifting anchors

Abstract

A shear bar for an edge lift anchor for a concrete panel, the shear bar being a bar shaped to provide a central portion to engage an upper edge of the lifting anchor when installed in the panel and legs inclining downwardly from each end of the central portion, the underside of each leg being profiled to lock into the surrounding concrete, the profiling being formed by a series of longitudinally spaced formations each of generally saw-toothed shape with a leading edge of each formation facing towards the central portion such that on application of shear load to the shear bar the leg will lock into the concrete with a generally compressive loading being applied to the concrete in the zone between the two legs.

1 . A shear bar for an edge lift anchor for a concrete panel, the shear bar being a bar shaped to provide a central portion to engage an upper edge of the lifting anchor when installed in the panel and legs inclining downwardly from each end of the central portion, the underside of each leg being profiled to lock into the surrounding concrete, the profiling being formed by a series of longitudinally spaced formations each of generally saw-toothed shape with a leading edge of each formation facing towards the central portion such that on application of shear load to the shear bar the leg will lock into the concrete with a generally compressive loading being applied to the concrete in the zone between the two legs. 
     
     
         2 . A shear bar according to  claim 1 , wherein each of the legs has an outer end portion extending substantially horizontally. 
     
     
         3 . A shear bar according to  claim 1 , wherein the shear bar is of rectangular cross-section having opposed large area faces and opposed smaller area faces and is so configured that the central portion engages the edge lift anchor with one of its large area faces. 
     
     
         4 . In combination, an edge lift anchor having a head portion for coupling to lifting apparatus and an anchoring portion extending from the head portion, and a shear bar according to  claim 1 , the central portion of the shear bar being engageable with an upper edge of the anchor. 
     
     
         5 . A combination according to  claim 4 , wherein the upper edge of the anchor has a planar portion engageable by the central portion of the shear bar. 
     
     
         6 . A combination according to  claim 4 , wherein the upper edge of the anchor is shaped so as to locate the shear bar.