The following is a tabulation of some prior art that presently appears relevant:
There are many methods for repairing concrete where the crack goes all the way through the concrete and has a gap. This type of crack can be called an open shrinkage crack. These gaps are often left unrepaired. The crack is often less noticeable than a repair. Adding a saw cut on top of a crack will conceal a crack by making it appear to be a saw cut control joint. Longer, wider or crooked cracks that have a gap can be filled with various products to protect against water intrusion, weed control, improve load transfer and improve general appearance. Structural repairs can include epoxy to bond pieces together, steel bars installed at intervals across a crack or a combination of both. A cracked concrete section can be cut out, demolished and replaced. Full slab removal and replacement may be an option when concrete is severely degraded or an exact color match is required.
All the crack repair methods heretofore known suffer from a number of disadvantages:
In accordance with one embodiment a new method for concrete crack repair comprises a saw cut control joint near the crack and placing expansive mortar in the saw cut to apply pressure inside the saw cut whereby it opens the saw cut and closes the crack. The saw cut is then cleared of expansive mortar and fitted with an epoxy plug to hold the saw cut in the open position. Epoxy is placed inside the closed crack to bond both sides of the crack together. A cosmetic treatment is now possible to the top of the closed crack and caulk to the opened saw cut.
Accordingly several advantages of one or more aspects are as follows: to provide a very tight crack, that is easy to cosmetically touch up, that increases load transfer across the crack, that develops interlocking action of aggregate particles on the face of the crack, that creates a control joint that isolates future movement, that spreads an active control joint, that transfers the width of the crack to the control joint, that is aesthetically pleasing, that is less noticeable, that will be bonded together with low viscosity epoxy, that produces the control joint that distracts the eye away from the closed crack, that eliminates the need to remove a concrete section, that eliminates the need to resurface or cover unsightly patching, that lowers the skill level required of craftsmen performing a crack repair, that can be cosmetically treated in similar ways as crusting cracks in decorative concrete, that eliminates the need to fill a crack, that eliminates caulking cracks, that reduces patching to pop outs that may have occurred along the top edge of a jagged crack, that reduces the labor required to make the repair, that can be held in place with the control joint spacer, that does not require coloring, that is aesthetically superior, that is easier to repair, that can be applied again to close the larger crack, that is economical, that increases job site profitability, that increases jobsite safety, that reduces the number of tools required to fix the job, etc.
One embodiment of a crack repair method is illustrated in
In one embodiment, expansive mortar is used to facilitate pressure inside the saw cut. However, the pressure can be developed from any other material that can be placed inside the saw cut that develops sufficient expandable pressure to open the saw cut, such as foam, plastic, polyethylene, polypropylene, vinyl, nylon, rubber, leather, various impregnated or laminated fibrous materials, various plasticized materials, cardboard, paper, etc.
In one embodiment, the rigid spacer used to hold the control joint is made of epoxy. The rigid spacer can be of made of any other material that can be placed inside the saw cut to hold the prescribed separation and the crack tightly in place, such as cement, mortar, foam, polyethylene, polypropylene, vinyl, nylon, rubber, leather, various impregnated or laminated fibrous materials, various plasticized materials, cardboard, paper, etc.
In one embodiment, gravity fed epoxy is used as adhesive to hold the cracked concrete pieces together. The adhesive can be of any other material installed in the crack designed to bond the pieces together. The adhesive can be installed before the crack closes, after closure or both. The adhesive can have long or short set times and consist of various materials such as film, fabrics, foam, polyethylene, polypropylene, vinyl, nylon, rubber, leather, various impregnated or laminated fibrous materials, various plasticized materials, cardboard, paper, etc.
In one embodiment, the saw cut is of sufficient depth to receive the expansive mortar. The saw cut can be of varying depths. Best results are achieved when the saw cuts down to the top of the steel reinforcement in the slab. The steel will remain in place and give support across the newly formed control joint. Sometimes reinforcement steel is too high in the slab and may inadvertently be cut when installing the saw cut control joint. Consequently, the concrete is supported by the compacted base material under it and the epoxy interlocking the crack at the bottom of the saw cut.
From the description above, a number of advantages of some embodiments of my new method for concrete crack repair become evident:
Accordingly, the reader will see that the new method for concrete crack repair of various embodiments can be used to repair cracks easily and conveniently, can be used where a control joint should have been installed, can produce better quality repairs, is an exact color match and is economical. In addition, when cracks are repaired, the active control joint created enhances the durability of the crack repair and so reduces jobsite call backs by increasing the repair performance. Furthermore, the new method for concrete crack repair has the additional advantages in that:
Although the description above contains much specificity, these should not be construed as limiting the scope of the embodiments but merely providing illustrations of some of the several embodiments. For example, the saw cut can have various sizes and shapes; the saw cut can have various depths; the shrinkage crack can be of various shapes, sizes and angles; the expansive mortar can be of various compositions of matter; the adhesive can be of various forms of matter; the closed shrinkage crack can be partially bonded; the adhesive can be omitted in the closed shrinkage crack; the epoxy bond inside the closed crack can individually hold the piece in place; the rigid spacer can be relied upon in combination with the interlocking aggregate to keep the pieces in place; the rigid spacer can be of any form of matter; the rigid spacer can be bonded to one side of the saw cut; the rigid spacer can be bonded to neither side of the saw cut; the rigid spacer can be bonded to both sides of the saw cut; the rigid spacer can be held in place by friction; the rigid spacer can have a finished the top surface to replace the caulk; the control joint can be held open with any form of matter, etc.
Thus the scope of the embodiments should be determined by the appended claims and their legal equivalents, rather than by the examples given.