Floor slab support system

Abstract

A floor slab support system for jacking and stabilizing a sagging or cracked floor or other such slab. Holes of 3½″ diameter, for example, are drilled through the slab and a pipe pier driven downwardly until reaching bottom. A connector sleeve matching the slab hole size is temporarily suspended in the slab hole and L shaped brackets are inserted into the sleeve and maneuvered to extend outwardly through slots in the sleeve to engage the underside of the slab. A threaded rod with a threaded positioning member and a bottom stop is inserted through the sleeve and into the pipe pier, and the L brackets extended through the sleeve and maintained outwardly by the threaded positioning member. Once in position, the threaded rod is rotated to screw the sleeve and brackets upwardly to support the slab. Finally, the top of the rod is cut off and the hole filled with concrete.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to correcting settlement of building slabs and more particularly, to structural devices for such procedures.

2. Description of the Prior Art

Basement walls and slabs have long been jacked up through hydraulic or screw jacks when settlement has occurred. The jacks connect to the walls through various bracket means, often a bolted plate, and the jack left in place. When used for jacking floor, driveway or other such flat slabs, a hole must be bored through the concrete and a spreader support of some type placed below slab level, then the jack extended to lift the slab. The spreader support has been the subject of development and outwardly expanding toggle bolts, crossbars, and the like used and all subject to expense.

SUMMARY OF THE INVENTION

The present invention consists of a sleeve which fits into a hole bored in the concrete slab and which has allowance for brackets to extend outwardly of the sleeve and engage with the bottom surface of the concrete slab. The brackets are L shaped and inserted when the sleeve is in position. Next a threaded rod that has a bottom stop nut and a threaded positioning member is inserted through the sleeve and rotated so that the positioning member engages with the L shaped brackets to maintain them in an outwardly extended position. The rod is screwed snug so that the brackets engage and lift the slab. Thereafter, the top of the rod can be cut off and the sleeve cemented in place.

OBJECTS OF THE INVENTION

The principle objects and advantages of the present invention are:

To provide an economical yet sturdy slab support system;

To provide such a slab support system which is easy to use; and

To provide such a slab support system which is well adapted to the intended purposes.

Other objects and advantages will become apparent from the following description including an exemplary embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal sectional view of a slab support system embodying the present invention and emplaced within a concrete slab.

FIG. 2 is an enlarged elevational view of an interior part of the slab support system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The reference numeral 1, FIG. 1, generally indicates a slab support system embodying the present invention. A hole 2 is bored in a concrete slab 3 and the system 1 sunk into the hole to bear a portion of the weight of the slab. The holes are bored in a grid arrangement, for example, every three to four feet on centers. The diameter of the hole may vary with the weight of the slab to be supported, but a typical system uses holes drilled 3½″ diameter.

A pipe pier 5 is driven downwardly through the bored hole until the pier bottoms out against hard resistance. Typically the pier is 16-18 feet long, emplaced by a hydraulic ram and pushed down until 10,000 psi resistance. The top of the pipe pier 5 ends inches below the lower surface of the floor slab.

A sleeve 10 is inserted, as by hand, into the bore 2 and temporarily retained therein by a L shaped brackets 16 and 18 are extended by hand through the sidewall slots 12 and 14 of the sleeve 10 so that the bottom leg of the L bracket rests against the underside of the slab 3.

To hold the L shaped brackets 16 and 18 in position and lift the sleeve 10 in support of the slab, a threaded rod 22 is fitted with a stop, such as a stop nut 24 welded or otherwise affixed adjacent the rod lower end, but leaving enough rod length to extend down into the open top of the pipe pier 5. A threaded positioning member 28, FIG. 2, is threaded to the rod 22, also adjacent its lower end and upwards of the stop nut 24. The positioning member 24 extends approximately 2⅝″ or the inner diameter of the sleeve 10, and is generally of elongate bar form. Opposite ends of the member 24 terminate in steps 30 and 32 so as to support the L corner of each L shaped bracket 16 and 18.

To engage the sleeve and position the L shaped brackets 16 and 18, the threaded rod 22 is extended downwardly through the sleeve 10 with the positioning member 28 rotated 90 degrees to avoid interference with the brackets 16 and 18. Once the rod is fully inserted and the stop nut 24 bears against the top of the pipe pier 5, the rod is rotated 90 degrees so that the positioning member contacts and supports the corners of each L shaped bracket 16 and 18, and tightening commenced. Once the rod 22 is tightened to installers recommended torque, the top exposed end of the rod 22 can be cut off and the sleeve 10 cemented or otherwise covered in place.

The brackets 16 and 18 hold the slab supported by the pipe pier. The brackets are far superior, stronger and less expensive than toggle bolts, bars, or other such load spreader mechanism.

It is to be understood that while certain forms of the invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.

Claims

1. A slab support and jacking system comprising:

a) a pipe pier extendable through an opening in said slab;

b) a threaded rod extendible into the pipe pier;

c) a connector sleeve adjustably mounted on said threaded rod and having outwardly extending L shaped slab supports protruding through said sleeve, the slab supports adjustably mounted on said threaded rod by a threaded positioning member.

2. The slab support and jacking system set forth in claim 1 wherein:

a) said threaded positioning member has opposite ends with steps for retaining the L shaped slab supports.

3. The slab support and jacking system set forth in claim 2 wherein said slab supports extend outwardly of said sleeve through slots in said sleeve.

4. A slab support and jacking system comprising a pipe pier extendable downwardly through an opening in said slab, a threaded rod extendable into the pipe pier and having a slab support threadably connected thereto for adjustably bearing against the slab, and the slab support including a sleeve member, a threaded connector on said rod and having L shaped opposite terminations and L shaped support arms extendable through slots in the sleeve member, the opposite terminations of the threaded connector holding said slab support arms and the threaded rod adjustable to rotate relative to the connector and move the sleeve and slab support arms upwardly.