A. B. Chance Company

Hubbell Limited

Robert M Hoyt

Daniel V Hamilton

Patricia J Halferty

J Thomas Odom

William M Rinehart

Edward Dziedzic

Donald E Bobbitt

Stanley C Garton

Gary E Bartee

William L Hoffman

J Paul Pilliard

James T Odom

A clamshell screw anchor is provided which is inexpensive to manufacture, installable in many types of soils including rocky and frozen soils, and is adaptable for use in various applications, such as supporting electric transmission poles. The screw anchor broadly includes a unitary body member, a core, and a helical load bearing element. The body member is stamped from a substantially flat piece of material, and presents a pair of opposed, elongated body segments depending from a line of symmetry. Each of the body segments includes a first end shaped to define a hub element having a C-shaped cross section, a second end shaped to define a lead point element, and a pair of longitudinally extending side edges. The body member is folded about the line of symmetry, and the body segments are secured together along the side edges so that the hub elements form a hub having an open, upper end, and a rectangular cross-sectional shape, and the lead point elements form a lead point having an earth-engaging tip. The core is positioned within the shell, and includes a first end adjacent to the first ends of the body segments, and an axially extending tapped bore formed in the first end. The core is attachable to elongated support rods used to support poles, towers, and the like. The helical load bearing element presents a leading edge, and a trailing edge adjacent to the open, upper end of the hub. The load bearing element facilitates installation of the anchor into the earth, and resists pulling and tensional forces exerted on the anchor once it is positioned.

Clamshell power installed screw anchor

An earth screw anchor assembly has peripheral edges on its hub member and intermediate flange portion of its spade member with different configurations permitting placement of the hub member on the intermediate flange portion in an asymmetrical relation overlapping and offsetting the respective peripheral edges relative to one another to facilitate application of welds thereto for attaching the hub member to the spade member. The assembly also has an attachment land formed on one side of the intermediate flange portion and protruding downwardly therefrom and being attached along and extending partially about an upper end of the lower portion of the spade member. The blade member includes leading and trailing end portions axially offset from one another and a middle portion extending between the leading and trailing end portions. The blade member at the trailing end and middle portions is attached to the hub member while the leading end portion thereof extends below and along the intermediate flange portion and is attached to the attachment land of the spade member so as to dispose the leading end portion of the blade member substantially below the intermediate flange portion and thereby below the lower end of the hub member such that the leading end portion of the blade member will engage and dig into the earth as the assembly is rotated about the longitudinal axis of said spade member before contact is made with the earth by the intermediate flange portion of the spade member and thereafter by the hub member.

Earth screw anchor assembly having enhanced penetrating capability

An earth anchor apparatus having reduced bending moment characteristics is provided, including a longitudinally extending hub having first and second axial ends. Affixed to the hub between the ends thereof is a radially extending load-bearing element, including a leading edge intersecting the hub and structure extending radially outward from the hub in a generally helical direction. The apparatus further includes an elongated anchor rod having first and second ends, and means for coupling the rod to the earth anchor. The coupling means includes means for reducing bending moments in the rod during movement thereof.

Reduced moment anchor hub

A low cost, easy to install underpinning apparatus (14) for supporting below-grade structural footings such as foundations (10) or the like is provided which makes use of a power installed, load-bearing helix-type screw anchor (16) together with a connecting bracket assembly (b 19) secured to the foundation (10). The anchor (16) is screwed into the earth below the foundation (10), leaving the upright end of the anchor shaft (20) adjacent the foundation (10). The bracket assembly (18) advantageously includes a foundation-engaging plate (28) with a pair of spaced, outwardly extending wall portion (30, 32) rigidly secured thereto. An elongated, U-shaped bracket (36) together with a mating retainer (42) are releasably secured to the wall portions (30, 32) and serve to captively retain the upper end of the anchor shaft (20), with the U-bracket (36) having a top crosspiece wall (38) provided with a threaded opening (40) therethrough. A threaded, force-transmitting bolt (54) screwed into the bracket crosspiece (38) engages the uppermost butt end (22) of the anchor shaft (20) so that the anchor (16) becomes a load-bearing support for the foundation (10). Rotational torque is imparted to each screw anchor during installation as a force independent of a respective support and the foundation until a predetermined torque value is achieved. The rotational torque on the screw anchor is then relieved and the dead weight and any live load of the building structure carried by the bracket assembly is transferred to the screw anchor.

Method of underpinning existing structures

A low cost, easy to install underpinning apparatus (14) for supporting below-grade structural footings such as foundations (10) or the like is provided which makes use of a power installed, load-bearing helix-type screw anchor (16) together with a connecting bracket assembly (19) secured to the foundation (10). The anchor (16) is screwed into the earth below the foundation (10), leaving the upright end of the anchor shaft (20) adjacent the foundation (10). The bracket assembly (18) advantageously includes a foundation-engaging plate (28) with a pair of spaced, outwardly extending wall portions (30, 32) rigidly secured thereto. An elongated, U-shaped bracket (36) together with a mating retainer (42) are releasably secured to the wall portions (30, 32) and serve to captively retain the upper end of the anchor shaft (20), with the U-bracket (36) having a top crosspiece wall (38) provided with a threaded opening (40) therethrough. A threaded, force-transmitting bolt (54) screwed into the bracket crosspiece (38) engages the uppermost butt end (22) of the anchor shaft (20) so that the anchor (16) becomes a load-bearing support for the foundation (10). Rotational torque is imparted to each screw anchor during installation as a force independent of a respective support and the foundation until a predetermined torque value is achieved. The rotational torque on the screw anchor is then relieved and the dead weight and any live load of the building structure carried by the bracket assembly is transferred to the screw anchor.

A low-cost easy to install underpinning apparatus (14) for supporting below-grade structural footings such as foundations (10) or the like is provided which makes use of a power installed, load-bearing helix-type screw anchor (16) together with a connecting bracket assembly (18) secured to the foundation (10). The anchor (16) is screwed into the earth below the foundation (10), leaving the upright end of the anchor shaft (20) adjacent the foundation (10). The bracket assembly (18) advantageously includes a foundation-engaging plate (28) with a pair of spaced, outwardly extending wall portions (30, 32) rigidly secured thereto. An elongated, U-shaped bracket (36) together with a mating retainer (42) are releasably secured to the wall portions (30, 32) and serve to captively retain the upper end of the anchor shaft (20), with the U-bracket (36) having a top crosspiece wall (38) provided with a threaded opening (40) therethrough. A threaded, force-transmitting bolt (54) screwed into the bracket crosspiece (38) engages the uppermost butt end (22) of the anchor shaft (20) so that the anchor (16) becomes a load-bearing support for the foundation (10).

Underpinning anchor system

An improved tower foundation is provided which is inexpensive to manufacture and when installed, serves to securely support a leg of power transmission towers and the like. The tower foundation hereof includes a screw-type earth anchor member having a tubular cavity at the uppermost end thereof. An elongated tower leg connector member is positioned and secured in the cavity of the installed anchor by an initially flowable, solidified material (preferably a sand/epoxy resin mixture). The tower leg connector member advantageously comprises a lowermost, tubular first portion and an uppermost, L-shaped in cross-section second, apertured connection portion, with the first and second portions having approximately coincidental centroidal axes. Preferably, the tower leg connector member is positioned in the cavity prior to setting of the solidifiable material, and can be adjusted as necessary for proper alignment and securement thereof to the tower leg, thereby compensating for slight anchor member installation error.

Method of providing support for an elongated tower leg

Tower-foundation anchor interconnection

A recoverable earth-retaining wall anchoring device and method is disclosed which allows the erection of a retaining wall in a quick, inexpensive manner and permits proof-load testing of the anchor during or immediately after installation, resulting in significant time and cost savings. The device includes a screw anchor having a central, elongated shaft with one or more outwardly extending helical blades affixed thereto, and an earth-penetrating lead point at one end. An adapter is attached to the anchor shaft and includes an opposed, threaded bore which receives an elongated threaded rod; a polygonal in cross-section engagement area is also provided between the opposed ends of the adapter. A wrench, having one or more releasably interconnected, tubular, polygonally-shaped shank sections is telescoped over the rod and operably and drivingly engages the adapter engagement area such that axial rotation of the wrench effects corresponding rotation of the anchor for installation and removal purposes. Multiple wrench shank sections are telescopically interfitted and releasably joined together by means of a spring biased locking dog inserted in aligned shank apertures. This dog is substantially flush mounted on the outer wrench section by means of an elongated, flat leaf spring which can be alternately positioned for maintaining the dog in a locking or a recessed position. The wrench may be easily removed from the soil because of the substantially flush configuration of the spring dog locking mechanism. The installation torque may be used to infer anchor load-bearing capacity and additionally, the device may be accurately proof-load tested and used immediately after installation, thereby eliminating costly construction delays. After the anchor is installed, the elongated rod is secured to the retaining wall thereby restraining the adjacent earth mass from lateral shifting.

Method and apparatus for anchoring retaining walls and the like, and

A lightweight, compact, portable pull-testing device is disclosed which is especially adapted for testing the load capabilities of installed, relatively small earth anchors such as those utilized with hold-down equipment for mobile homes or the like. The device includes a tripod-mounted, vertically adjustable, hydraulically actuated piston and cylinder assembly securable to the upper protruding end of an earth anchor shaft, with generally upright tripod support legs positioned closely adjacent the protruding shaft end to permit use of the device by a single operator in crowded areas such as beneath a mobile home where space is at a premium. Novel creep indicator apparatus is also disclosed for the accurate measurement of anchor creepage independent of any settling of the device itself into the earth which may occur during pull testing.

Growing community of inventors

Centralia, MO, United States of America

Robert M Hoyt