Concrete is most-commonly found in the sidewalks, curbs, gutters, and ramps of a property. Unlike asphalt, which is laid and compacted, concrete is poured into specialized forms until it cures or hardens enough to hold its shape. Concrete’s compressive strength is specified by its PSI (pounds of pressure per square inch) rating. Concrete has almost no tensile strength unless reinforced by rebar, wire mesh, or steel cable. 3-D Paving & Sealcoating has dedicated crews who specialize in the installation and repairs of all your concrete.
Concrete sidewalks are 4” (6” when supporting vehicular traffic) thick slabs formed and poured to create a pedestrian walkway. Expansion joints are installed between slabs, or flags, to prevent the concrete from buckling due to expansion. Concrete is extremely durable and does not fail structurally unless extenuating environmental circumstances have affected the sidewalk.
Concrete slabs are used in many warehouses and parking garages, as well as dumpster pads and aprons. Concrete slabs tend to be thicker than a regular sidewalk, ranging from 6” to 18”. Additionally, concrete slabs are usually poured from a higher PSI concrete mix than sidewalks since they support more weight. Concrete slabs are also reinforced with either wire or fiber mesh, or with rebar, to add tensile strength.
Sidewalks and slabs can be repaired by first addressing the cause of the failure. If the concrete is damaged due to tree roots or an erosion of the base rock underneath, the area for the repair is first removed using a professional grade wet saw. Any exposed roots are saw-cut or ground down, and any missing base rock is reinstalled and compacted to form a suitable base. Wooden or steel forms are used to create the mold for the new concrete. Once the forms are in place, concrete is poured into the forms and allowed to cure. The slabs are brushed with a broom which creates a textured surface and prevents slippage. Finally, the forms are stripped and the area is cleaned of all debris. If necessary, controlled joints may be saw-cut as well.
Concrete curbs and gutters (which are technically a type of curb) are found alongside crown roads, at the center of inverted roads, or around landscaping and sidewalks to provide a suitable border. There are many types of curbing, depending on their intended functionality. Curbing can be extruded directly on top of asphalt or concrete, or it can be trenched below the surface. Additionally, some types of curbing require a “pad” of base rock underneath.
Curb repairs tend to be made necessary by either tree roots or vehicular collisions. Regardless of the type of curb you have, the first step is removing the damaged existing curb. Once the old curb has been taken out, the cause of the damage is assessed. Tree roots that are exposed may need to be saw-cut and removed or ground down with a stump grinder. Additionally, trenching may be necessary for the new curb depending on what type of curbing is being installed. If the new curb requires a curb pad, this is the time where the base rock may be supplied, installed, and/or properly compacted to create a suitable base.
Once the area is properly prepped, curb mix concrete is loaded into a curbing machine. This machine runs the length of the area slowly leaving new curb in its wake. The edges of the new curbing are finished by hand, and any forms used are cleaned and stripped once the curb cures.
Occasionally, adjoining sidewalk slabs may have a slight height differential between them as one or both flags are lifted or sunk due to environmental conditions. These differentials are a trip hazard and should be addressed immediately to reduce the potential for liabilities. If this height differential is greater than ½”, one or both of the flags need to be completely replaced. If, however, this height differential is ½” or less, it may be possible to create a smooth transition between flags by grinding down the edges of one or both slabs.
Concrete ramps and steps allow pedestrian to access your property from a lower elevation. Steps can traditionally be found when the transition between adjoining elevations is greater than 6”. Ramps allow for easier access and are generally sloped at a ratio of 1” height to 12” of run to comply with the Americans with Disabilities Act (ADA.)
Ramps and steps are repaired similarly to sidewalks and slabs. First, the damaged concrete is saw-cut and removed with a professional grade wet saw. For new installations, the area is excavated to a proper depth to allow for a limerock base. Next, forms are built in the correct shape before the concrete is poured. The concrete is then finished with a broom for a textured finish, and then the forms are stripped and cleaned once the concrete cures.