The concrete trade involved in flat work, including sidewalks, pads and slabs, includes a variety of concrete pouring and finishing steps, including form layout and construction, rebar cutting and installation, concrete pour, vibration of the poured concrete to eliminate voids and settle the concrete evenly throughout the form and in contact with the rebar, and the various finishing steps. These latter include using a screed board to initially form the surface evenly level from side to side and front to back of the formed area, followed by formation of expansion joints with a deep jointer tool, edge smoothing and forming with an edge tool, and floats.
For the main area, a large, wide bull float (dimensions 6-12″ wide by 3-8′ long, typically 4′ long) that is manipulated by a long aluminum pole-type handle, is used. The handles are typically 6′ in length, and multiple handles can be joined in series to make handles 6× in length, e.g., 12′, 18′, 24′ and the like. This permits the worker standing off to the sides of the work to smooth the surface with the bull float, reaching the full dimensional area that is being poured. However, moving the bull float forward and back or side to side, and near edges and corners often leaves gouges or depressions in the concrete. For example, the forward edge of the float may dip into the concrete rather than skidding across the surface, leaving a gouge or mark. Likewise the deep jointer may leave marks, tails, ridges or unwanted gouges.
The problem here is that the depression or gouge may fill with Portland cement, but be lacking in aggregate. While it may look and may actually be level, the pure Portland cement skin is not durable when thick as needed to fill the depression, and the job is not acceptable.
Current practice is for the finisher to use a knee board placed on the surface of the fresh pour within a few feet of the imperfection. The finisher kneels on the board, and reaches out with a small hand float, which is on the order of 12″ to 18″ in length by 3.5″ wide (the most common being 16″ in length), to smooth out the imperfection. However, the knee board compresses the aggregate down into the pour, and it in turn must be reworked or filled and floated in order that the Portland cement skim coat is uniform. In addition, if the imperfection is some distance from the form edge, a number of knee boards may have to be laid out on the work in order to reach the imperfection, and each knee board depression must be reworked in series from the innermost to the edge. In large pours, there may be from 3-6 or more knee board depressions that have to be worked out per original depression or gouge.
Thus, the present practice in the field simply trades one problem for another: knee board depressions for bull float and jointer marks and imperfections. There is no known tool that permits deep reach across a wide slab for lay down, dressing or other preparation for final finishing with a hand float.
Accordingly, there is an unmet need in the art for a tool that permits long reach of a hand-type float into a work area to work out imperfections left by previous concrete working steps.
USPTO Backgrounds
USPTO Backgrounds