What is the porosity of concrete?

What is the porosity of concrete?

Porosity is a measure of the volume of voids in concrete. Permeability is the rate of flow of moisture through concrete under a pressure gradient. Voids through which moisture can move must be interconnected and of a certain size. Discontinuous pores and pores with narrow entrances retard flow of moisture.

What is considered permeable?

Permeable surfaces (also known as porous or pervious surfaces) allow water to percolate into the soil to filter out pollutants and recharge the water table. Impermeable/impervious surfaces are solid surfaces that don’t allow water to penetrate, forcing it to run off.

What is porous concrete used for?

Porous concrete is applicable to many light-duty uses, including overflow parking areas, residential street parking lanes, parking pads in parking lots, sidewalks, golf cart and bike paths, and emergency access lanes.

What is porosity of aggregate?

Porosity of aggregates is their dominant quality determinant. Porosity governs specific gravity, and determines the physical durability of aggregates. Porosity and permeability often, but not necessarily correlate – i.e., large porosity does not always indicate high permeability.

Is porosity good for concrete?

The porosity of concrete has influence on the properties in many aspects. Composition of concrete, casting in practice, maturing and hardening, cement reactions and risks at freezing, all are influenced by porosity. The possibilities to influence the type of porosity are important.

What is an example of an impervious surface?

Impervious Surface Definition: Surfaces that allow little to no water to pass through. Examples of impervious surfaces are roofs, parking lots, compacted soil, and streets or anything else made from asphalt, concrete or plastic that does not allow water to infiltrate into the ground.

How does porosity affect concrete?

The primary factor that governs the strength of brittle materials, like concrete, is porosity. As the capillary porosity decreases compressive strength increases. Also there is data to indicate that large pores may be more effective than small pores in reliving stress concentrations at crack tips.