MASONRY ANCHOR

摘要

An expansion sleeve (4) for a masonry anchor has circumferentially-spaced apertures (6) intermediate the ends of the sleeve. The apertures are shaped so that a land (14) is defined between adjacent apertures (6) to form an inclined strut (14) operative to deform as a result of axial loading applied to the sleeve whereby to result in a contraction in the axial length of the sleeve. Each aperture is so shaped that an abrupt change (4) in the direction of the edge of the aperture defines a point at which the adjacent strut starts to deform as a result of stress concentration arising at the point under the applied load. The abrupt change in direction occurs at positions substantially at each axial end of the apertured region defined in the sleeve by the apertures. The defined stress concentration points provide determinable characteristics for the contraction of the sleeve which facilitates "pull down" upon setting of the anchor.