#nrmca

Pervious concrete is a special type of concrete with a high porosity used for concrete flatwork applications that allows water from precipitation and other sources to pass through it, thereby reducing the runoff from a site and recharging ground water…

Surface discoloration is the non-uniformity of color or hue on the surface of a single concrete placement. It may take the form of dark blotches or mottled discol- oration on flatwork surface, gross color changes in large areas of concrete caused by a…

Crazing is the development of a network of fine ran- dom cracks or fissures on the surface of concrete or mortar caused by shrinkage of the surface layer. These cracks are rarely more than 1/8 inch [3 mm] deep and are more noticeable on steel-troweled…

  WHAT is Jobsite Addition of Water?

Jobsite addition of water is the addition of water to ready mixed concrete in a truck mixer after arrival at the location of the concrete placement. Such temper- ing of concrete may be done with a portion of the…

Concrete, like other construction materials, contracts and expands with changes in moisture and tempera- ture, and deflects depending on load and support condi- tions. Cracks can occur when provisions to accommo- date these movements are not made in…