Gravel supply

Gravel (pebbles). Mountain and river, fr.5-20 mm, 20-40mm and large, fraction over 40 mm. GOST 8267-93

The mountain has a rough surface and usually contains impurities of sand, clay and organic substances. River gravel is cleaner than mountain gravel, but its grains have a smooth surface, which significantly impairs adhesion to cement-sand mortar in concrete. Pebbles are used in road construction, as well as for decorative purposes.