Improvements in and relating to anchorage means for prestressing and post-tensioning cables and the like

摘要

846,346. Pre-stressed &c. concrete. REINFORCING STEEL CO. (Proprietary) Ltd. March 19, 1958 [March 25, 1957], No. 8799/58. Class 20(4) An anchoring device for securing. prestressed or post-tensioned rods 16 in the construction of concrete structures comprises a thrust block 1 bearing on one end of the structure 7 and having a tapered hole 3 converging in the direction of the concrete engaging face of the block, and a number of similar wedges for location within the hole each wedge being provided with longitudinal grooves 12 for engaging surface regions. of the rods. A stressed or tensioned rod is anchored between the converging face of the hole 3 and a groove in an outwardly directed face of each wedge, and a stressed or tensioned rod is clamped between the grooves in each pair of substantially, radially disposed, coacting faces of adjacent wedges, the rods being disposed in spaced relation along two concentric circles within the device. As shown, the cast iron or steel thrust block 1 has an integral collar 2 and is formed with a recess 5 which receives the end of at duct casing: 20 surrounded by a helical reinforcing wire 21. The steel wedges 10 are of triangular cross-sectional shape and have therein grooves 12 of semi-circular cross-section of a. radius equal to or slightly smaller than that of the rods.. A tubular element is engaged over the collar 2 for introducing grout into the duct: 20.