FOUNDATION REPAIR SYSTEM UTILIZING DISSOLVABLE SPACERS

Abstract

A foundation repair system which employs dissolvable spacers to reduce installation force during pier shimming operations. The system includes concrete piers driven to refusal, topped with pier caps and pier cylinders. A dissolvable spacer is positioned on top of one cylinder, creating a temporary elevation. This allows corrosion-resistant shim plates to be installed on an adjacent pier cylinder with reduced hammering force, decreasing installation impact and preventing pier damage. The dissolvable spacer naturally dissolves when exposed to moisture, leaving little to no residual material. The system may also incorporate galvanized or stainless-steel shim plates for corrosion resistance, and double-stacked pier caps for enhanced load distribution. The method addresses installation force problems that cause pier cracking, while providing long term structural durability.

Claims

1. A system for foundation repair, comprising: a concrete pier driven into soil until refusal is reached or adequate bearing capacity is achieved; a metallic reinforcement inserted into the concrete pier; a pier cap positioned on top of said concrete pier; a first and a second concrete cylinders positioned on said pier cap; a dissolvable spacer positioned on top of said first concrete cylinder; one or more shim plates positioned above said dissolvable spacer; and one or more shim plates positioned on top of said second cylinder.

2. The foundation repair system of claim 1, wherein the dissolvable spacer is allowed to dissolve over time.

3. The foundation repair system of claim 1, wherein said concrete pier is cylindrical with a diameter of 6 or 8 inches and a length of 12 inches.

4. The foundation repair system of claim 1, wherein the metallic reinforcement comprises rebar or rods made of galvanized steel, stainless steel, or plain carbon steel.

5. The foundation repair system of claim 1, wherein said pier cap comprises a double-stacked concrete configuration.

6. The foundation repair system of claim 1, wherein said dissolvable spacer is made from a material selected from the group consisting of carton paper, compressed fiberboard, corrugated cardboard, and biodegradable polymers.

7. The foundation repair system of claim 1, wherein said dissolvable spacer is made of carton paper.

8. The foundation repair system of claim 1, wherein said shim plates are shaped as square, rectangular, or round.

9. The foundation repair system of claim 1, wherein said shim plates are made of galvanized or stainless steel and have a thickness between 0.25 and 1 inch.

10. The foundation repair system of claim 9, wherein said shim plates are shaped as square, rectangular, or round.

11. A method for foundation repair, comprising the steps of: installing a concrete pier using a kinetic force until refusal or adequate bearing capacity is reached; inserting metallic reinforcement into the concrete pier; positioning a pier cap on top of said concrete pier; installing a first and a second concrete cylinders on said pier cap; placing a dissolvable spacer on top of said first concrete cylinder; installing one or more shim plates above said dissolvable spacer; and installing one or more shim plates on top of said second cylinder.

12. The method of claim 11, further comprising the step of allowing the dissolvable spacer to dissolve over time.

13. The method of claim 11, wherein said concrete pier is cylindrical with a diameter of 6 or 8 inches and a length of 12 inches.

14. The method of claim 11, wherein the metallic reinforcement comprises rebar or rods made of galvanized steel, stainless steel, or plain carbon steel.

15. The method of claim 11, wherein said pier cap comprises a double-stacked concrete configuration.

16. The method of claim 11, wherein said dissolvable spacer is made of carton paper.

17. The method of claim 11, wherein said shim plates are made of galvanized or stainless steel and have a thickness between 0.25 and 1 inch.

18. The method of claim 11, wherein said shim plates are shaped as square, rectangular, or round.

19. The method of claim 17, wherein said shim plates are shaped as square, rectangular, or round.

20. The method of claim 11, further comprising the step of applying water to said dissolvable spacer to accelerate dissolution.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 is a cross-sectional side view illustrating a foundation repair system with the dissolvable spacer installed on the right pier to reduce installation force required for installation of shim plates on the left pier.

[0012] FIG. 2 is an exploded perspective view showing the individual components of the foundation repair system, including the concrete piers, pier cap, dissolvable spacer, and shim plates.

[0013] FIG. 3 is a cross-sectional side view similar to FIG. 1, but showing the foundation repair system utilizing double-stacked pier caps.

[0014] FIG. 4 comprises a top and side view of shim plates in round, square, and rectangular configurations, with dimensional indicators.

[0015] FIG. 5 is a schematic view showing a residential foundation system with multiple pier installations beneath a structure, illustrating the practical application of the foundation repair method.

DETAILED DESCRIPTION

Detailed Description of Embodiments and Aspects

[0016] Accordingly, the inventor has conceived and reduced to practice, a system and method for repairing foundations utilizing force-reduction and corrosion-resistant materials, as depicted in FIG. 1. The pier assembly 100 is used to support an existing foundation structure. Each pier assembly 100 comprises a cylindrical foundational concrete pier 101, typically between 6 and 8 inches in diameter, and 12 inches in length. These piers 101 are driven into the ground with hydraulic pressure, ranging from 6,000 psi to 10,000 psi, until the point of refusal is reached, which is the point at which additional driving force fails to yield further penetration, indicating contact with load-bearing soil or bedrock.

[0017] Once installed, the pier 101 is given internal reinforcement using metallic rods or rebars made from galvanized steel, stainless steel, or plain carbon steel. The reinforcement rods range in diameter from inch to inch, and vary in length between 12 to 18 inches, depending on installation depth and local soil conditions. This internal reinforcement provides tensile support and enhances pier strength.

[0018] A pier cap 102 is installed on top of the foundational pier 101 to distribute the load from the foundation structures to the pier. The pier cap is often a precast or fabricated concrete block with dimensions ranging from 8814 to 8816. To enhance stability and counteract eccentric loading from misaligned jacks during lifting, the system can employ a double-stacked pier cap configuration, as depicted in FIG. 3. The double-stacked pier caps 301 in pier assembly 300 increase the load transfer surface area and reduce shear stress, improving load stability and structural integrity.

[0019] In several embodiments, the system includes two subsequent concrete pier cylinders 103a and 103b, which may be sized at 8814 or 8816, which are placed atop the pier cap. These cylinders provide support between the pier cap and the foundation structure, with shim plates being used for final leveling adjustments. Prior to shim plate installation, a dissolvable spacer 104 is placed on top of one of the two pier cylinders, typically 103a. This dissolvable spacer 104 may be constructed from carton paper, compressed fiberboard, corrugated cardboard, or biodegradable polymers, all of which can provide sufficient support with a slight cushioning effect during installation while dissolving over time when exposed to environmental moisture, leaving little to no residual material to interfere with permanent structural alignment or load distribution. The rate of dissolution may vary depending on conditions such as humidity, rainfall, or other environmental conditions. The rate of dissolution may also be increased rapidly by intentionally applying water to the spacer material.

[0020] On top of the dissolvable spacer 104, one or more corrosion-resistant shim plates 105a are stacked, the number of which is determined by the required elevation adjustment. The dissolvable spacer 104 creates a controlled spacing, and allows for a number of corrosion-resistant shim plates 105b to be installed on top of the remaining cylinder 103b with reduced hammering force, the number of which is also determined by the required elevation adjustment.

[0021] Field testing was conducted at multiple residential foundation repair projects between November 2024 and May 2025. A total of eighteen paired comparisons (thirty-six piers) were performed, with each pair consisting of one pier installation using the dissolvable spacer technique and one using conventional direct shim placement. The installer performed both methods in each pair with identical shim plates and pier/cap configurations to minimize variability. Across all tests, the dissolvable spacer installations required on average approximately thirty-four percent fewer hammer strikes to fully seat the final shims, and no instance was observed in which the spacer-assisted installation required equal or greater strikes than the conventional method. All spacer-assisted installations seated with light to moderate tapping force and exhibited no visible cracking in the pier or pier cap, whereas conventional installations consistently required full-force hammering and produced minor to major cracking. These results demonstrate that the dissolvable spacer reduces installation force, eliminates cracking, and provides consistent performance improvements across multiple projects and installers.

[0022] These results were unexpected in view of known foundation shimming techniques, which typically require high-impact hammering and often result in cracking of piers or pier caps. No known references in the field of foundation repair describe or suggest the use of a dissolvable spacer to provide temporary clearance for shim insertion, nor that such a spacer would reduce force sufficiently to eliminate observable cracking. The consistent reduction in hammer strikes and the absence of cracking across multiple installers and projects indicate a functional improvement not predictable from known shimming practices or from routine substitution of materials.

[0023] The shim plates can be made in multiple materials, sizes, and shapes, as illustrated in FIG. 4. In preferred embodiments, these plates are made from corrosion-resistant materials, typically galvanized steel or stainless steel. The shim plates are of various shapes (round 400, square 403, and rectangular 406) The round shape plates 400 conform to the top of cylindrical piers, uniformly distributing weight and preventing stress points that may lead to structural failure. These round plates may range in diameter 401 from 4 to 8 inches, and thickness 402 from to 1 inch. Square shim plates 403 may range in size 404 from 44 to 88, and thickness 405 from to 1 inch. The rectangular shim plates 406, have a length 407a and width 407b often ranging from 4 to 8 inches, and thickness 408 from to 1 inch.

[0024] FIG. 5. Illustrates a foundation repair installation showing multiple pier assemblies 100 positioned beneath a residential structure. The foundation beam 501 spans multiple pier locations, with multiple pier assemblies spaced at appropriate intervals along the foundation. The piers are driven into the soil 500 until the point of refusal is reached. During installation, the dissolvable spacer technique is applied systematically across each pier location. Prior to foundation lifting, dissolvable spacers 104 are positioned on cylinder 103a of each pier assembly to create the controlled spacing necessary for reduced-force shim installation. Once the foundation is lifted to the desired elevation, the spacers allow shim plates 105b to be installed on cylinder 103b with significantly reduced hammering force. The installation sequence progresses systematically across multiple pier locations, with each subsequent pier benefiting from the force reduction methodology. Quality control measures include verification of spacer placement before lifting operations, monitoring proper hydraulic jack alignment to prevent eccentric loading, and documentation of spacer dissolution progress over the subsequent weeks following installation.

[0025] The inventor has conceived and reduced to practice a system for foundation repair that addresses the force intensive installation challenges described above. The system comprises a concrete pier driven into soil using kinetic, often hydraulic, force until refusal is reached or adequate bearing capacity is achieved, providing stable foundation support regardless of soil conditions. The system further includes a metallic reinforcement inserted into the concrete pier to enhance the capacity of the pier; a pier cap is positioned on top of the concrete pier to distribute loads from the foundation structures to the pier assemblies. The system incorporates a first and second concrete cylinder positioned on the pier cap, a dissolvable spacer positioned on the first of the two cylinders, one or more shim plates placed above the dissolvable spacer, and one or more shim plates placed on top of the second cylinder.

[0026] The inventor has also created various embodiments and aspects of the foundation repair system, which include but are not limited to a foundation repair system wherein the dissolvable spacer is allowed to dissolve over time when exposed to environmental moisture. Additional embodiments include a foundation repair system wherein the concrete pier is cylindrical with a diameter of 6 or 8 inches and a length of 12 inches. Further variations include a foundation repair system wherein said metallic reinforcement comprises rebar or rods made of galvanized steel, stainless steel, or plain carbon steel with diameters ranging from to inch. The inventor has also conceived a foundation repair system wherein said pier cap comprises a double-stacked concrete configuration. Other embodiments include a foundation repair system in which the dissolvable spacer is made of carton paper, a system wherein the shim plates are made of galvanized or stainless steel and have a thickness between 0.25 and 1 inch. The inventor has embodiments of the system wherein said shim plates are shaped as square, rectangular, or round. An additional embodiment includes a system foundation repair system in which the shim plates are round and specifically configured to conform to a circular top surface of said concrete cylinders.

[0027] The inventor has further conceived and reduced to practice a method for foundation repair, comprising the steps of installing a concrete pier using a kinetic force until refusal or adequate bearing capacity is reached, inserting metallic reinforcement into the concrete pier, positioning a pier cap on top of said concrete pier, installing a first and a second concrete cylinders on said pier cap, placing a dissolvable spacer on top of said first concrete cylinder, installing one or more shim plates above said dissolvable spacer, and installing one or more shim plates on top of said second cylinder.

[0028] The inventor has also conceived various embodiments of the foundation repair method, which include, but are not limited to a method further comprising the step of allowing the dissolvable spacer to dissolve over time through exposure to environmental moisture, and a method wherein said concrete pier is cylindrical with a diameter of 6 or 8 inches and a length of 12 inches for standardized installation procedures, as well as a method wherein said metallic reinforcement comprises rebar or rods made of galvanized steel, stainless steel, or plain carbon steel based on environmental conditions and structural requirements. Additional embodiments include a method wherein said pier cap comprises a double-stacked concrete configuration providing enhanced load distribution and improved tolerance for hydraulic jack misalignment, and a method wherein said dissolvable spacer is made of carton paper or biodegradable polymer materials that maintain installation integrity while ensuring predictable dissolution characteristics. Further variations encompass a method wherein said shim plates are made of galvanized or stainless steel and have a thickness between 0.25 and 1-inch providing corrosion resistance and accommodation for various elevation adjustment requirements, as well as a method wherein said shim plates are shaped as square, rectangular, or round.