Settlement is often caused by inadequate soil or base compaction. Other factors can be water in the base or soil, too thick a layer of bedding sand, or washed out bedding and joint sand. Loose or inadequate edge restraints will cause pavers to move apart. Pavers in uneven areas can be removed, the settlement adjusted, and the units reinstalled with no wasted paving materials or unsightly patches. If the base or soil has settled and is stable, remove the pavers and bedding sand, place and compact additional base material to the correct level, then add bedding sand. Bedding sand alone shouldn’t be applied to adjust the level of the surface if its thickness exceeds 1 1/2 in. (40 mm).
Concrete pavers can be removed for access to underground utilities, and reinstalled after repairs. When utility repairs are complete, fill the trench with base material and compact it. Remove about 18 in. (0.5 m) of pavers on either side of the opening, level the bedding sand and replenish as necessary. Re install the pavers, compact, fill the joints with sand and compact the surface again, filling joints as needed. ICPI Tech Spec 6-Reinstatement of Interlocking Concrete Pavements, provides step-by-step guidelines on removal and replacement of concrete pavers.
Color in concrete pavers is achieved by adding pigment to the concrete mix during production. The cement in the concrete mix holds the pigments in place. Normal wear form traffic or weather gradually erodes the cement and pigment particles, causing a color change over time.
Like all pavements, concrete pavers receive dirt from foot or tire traffic which changes the surface color. Cleaning and sealing the surface of the concrete pavers can moderate the rate of color change. Besides enhancing the pavers’ color, sealers can prevent dirt from lodging in their surface.
Weeds can germinate between pavers from windblown seeds lodged in the joints; they don’t grow from the bedding sand, base or soil. Weeds can be removed by hand or with herbicides. Take care in using herbicides so that adjacent vegetated areas are not damaged. Use biodegradable products that won’t damage other vegetation or pollute water supplies when washed from the pavement surface. Besides stabilizing the joint sand, sealers can prevent seeds from germinating, and prevent ants from entering.
Concrete pavers aren’t damaged by petroleum products, but driveway oil leak stains from cars can be difficult to remove. Stains should be treated as soon as possible. The longer they remain on the surface, the deeper they penetrate and are harder to remove.
First, wipe excess oil from the surface and apply liquid detergent. Allow it to soak for several minutes and wash the pavers with hot water. Several treatments may be necessary to remove particularly stubborn stains. For best results use cleaners specially made for removing oil stains from concrete paves. Keep in mind that due to their modular nature and ease of replacement it is simple to replace severely stained or damaged pavers when needed.
Cleaning and sealing concrete pavers early in their life can make removing stains easier, since sealers prevent stains from soaking into the surface. The sealers may need to be reapplied from time to time due to wear and weather. Concrete pavers should be cleaned prior to sealer application to obtain the best performance and appearance.
Removing oil and many other stains is discussed in Tech Spec 5 – Cleaning and Sealing Interlocking Concrete pavement – A Maintenance and Protection Guide. A thorough review of stain removal is also addressed in the booklet, Removing Stains from Concrete, The Aberdeen Group. Your paver supplier can provide information on cleaners and sealers specifically made for concrete pavers.
Here are some pics and video of a project were working on in Naples called Allegro.
Allegro ProgressWatch Video