Sidewalk Grinding Specifications
This specification describes a grinding procedure for one operator to quickly reduce raised sidewalk panels (“risers” or “trip hazards”) up to 2” high only. Any risers greater than 2” high are normally replaced.
Equipment Needed:
- Dry cutting scarifier
- Flail-It Tungsten carbide spike cutters
A dry-cutting scarifier outfitted with “flail-it” tungsten carbide spike cutters will quickly reduce the raised sidewalk panel level through the pulverizing scarification process that tapers down the hard risers into fine concrete powders.
The final surface will have a smooth “non-slip” CSP3–CSP4 textured surface finish without any rough edges.
The completed panel will have a surface color shaded lighter than the adjoining section.
Any remaining concrete powders shall be collected from the sight by broom. A dust collector can be connected to the vacuum port to contain airborne fine concrete powders.
The raised panel “riser” shall be tapered using the following formula to produce an even transition:
|
Riser |
Tapered |
|
1/4" |
2” |
|
1/2" |
4” |
|
3/4" |
6” |
|
1” |
8” |
|
1 1/4" |
10” |
|
1 1/2" |
12” |
|
1 3/4" |
14” |
|
2” |
16” |
Equipment selection:
Scarifier machines are drum-style flailing surfacers available in different size and weight classes, from portable handhelds, to walk-behinds, self-propels, and ride-ons. Productivity is dependent upon machine weight, horsepower, cutter size and drum width. Finishes can be controlled by the operator’s skill, equipment selection, and the flail-it cutter drum set-up pattern.
The most common sidewalk grinders are walk-behinds ranging from 125 lbs to 450 lbs.
- Light class scarifiers (125 lbs, 5.5HP, 1 5/8” cutter, 8” widths) - ideal for managing many small jobs up to 1/4” or very limited risers over 1/4”.
- Medium class scarifiers (240 lbs, 13HP, 2 1/4” cutter, 10” widths) - most popular and best suited for every type of surface prep job especially sidewalk risers up to 2”.
- Heavy class scarifiers (450 lbs, 13HP, 3 1/4” cutter, 15” widths) - best suited for professional concrete refinishers requiring the heaviest and most productive equipment.
- Handheld (15 lbs, 1.3 HP, 1 1/4” cutter, 2” widths) - best suited for working in tight locations and for squaring-up the scarifier’s finishes.
