Patent ID: 8302276
Filing Date: 2012-11-06
Classification: F16B,G01N,Y10T

Abstract:
1. A method of performing cracked concrete testing in a borehole, defined within a concrete substrate, using an anchor assembly, comprising the steps of: providing a borehole within a concrete substrate; anchoring an anchor assembly within said borehole defined within said concrete substrate so as to meet cracked concrete testing standards, wherein said anchor assembly comprises an anchor bolt member comprising a substantially cylindrical member formed about a longitudinal axis; an externally threaded load-application portion formed upon a rearward end portion of said anchor bolt member; an enlarged head member formed upon a forward end portion of said anchor bolt member and comprising an enlarged cylindrical portion and a frusto-conical portion integrally interconnecting said cylindrical portion of said enlarged head member to said cylindrically configured anchor bolt member, said frusto-conical portion having a predetermined radially outward angular inclination with respect to said longitudinal axis of said anchor bolt member as considered in the direction extending from said rearward end portion of said anchor bolt member toward said forward end portion of said anchor bolt member; an annular shoulder member integrally formed upon said anchor bolt member at a predetermined axial location upstream of said frusto-conical portion of said enlarged head member; and an expansion sleeve member annularly disposed about said anchor bolt member and having a substantially C-shaped cross-sectional configuration, defined around a longitudinal axis, so as to define an axial slit all along its axial extent, extending from a downstream end portion thereof to an upstream end portion thereof, so as to permit said expansion sleeve member to immediately open and expand radially outwardly, into engaged contact with interior wall portions of said borehole defined within said concrete substrate, when said anchor bolt member is pulled through said expansion sleeve member as a result of an application load being applied to said externally threaded load-application portion of said anchor bolt member, wherein an internal surface portion of said downstream end portion of said expansion sleeve member has a predetermined radially outward angular inclination with respect to said longitudinal axis of said expansion sleeve member, as considered in the direction extending from said rearward end portion of said anchor bolt member toward said forward end portion of said anchor bolt member, which is substantially the same as said angular inclination of said frusto-conical portion of said enlarged head member of said anchor bolt member such that said internal surface portion of said downstream end portion of said expansion sleeve member can be disposed in surface-to-surface contact with said frusto-conical portion of said enlarged head member of said anchor bolt member as a result of said upstream end portion of said expansion sleeve member being disposed in seated contact with said annular shoulder member of said anchor bolt member, and wherein further, a plurality of annular grooves are disposed only upon a forward external peripheral portion of said expansion sleeve member, while a rearward external peripheral portion of said expansion sleeve member is non-grooved and solid; and using a torquing assembly for imparting a predetermined torquing load to said anchor bolt member such that said enlarged head portion of said anchor bolt member expands said forward portion of said expansion sleeve member so that said plurality of annular grooves are forced into engagement with internal peripheral side wall portions of said borehole defined within said concrete substrate so as to define increased areas and volumes of interference with said internal peripheral side wall portions of said borehole defined within said concrete substrate, and is disposed entirely within the rearward portion of said expansion sleeve member so as to expand said rearward portion of said expansion sleeve member such that said non-grooved solid portion of said expansion sleeve member is forced into engagement with said internal peripheral side wall portions of said borehole defined within said concrete substrate so as to achieve, at said predetermined torquing load, a maximum interference area (M.I.A.) and maximum interference volume (M.I.V.) with said internal peripheral side wall portions of said borehole defined within said concrete substrate so as to enhance the holding power and pull-out resistance of said anchor assembly with respect to said borehole defined within said concrete substrate.