4.6.3 Rock Density The density of rock used for riprap typically varies from about 2,400 kg/m3 (150 lb/ft3) to 2,800 kg/m3 (175 lb/ft3), with a density of about 2,600 kg/m3 (162.5 lb/ft3) common for the granitic or granodioritic rocks that are often quarried in British Columbia.
How thick should rip rap be?
The riprap layer thickness should never be less than 2D50. There should be a well-graded bedding layer with a specified D54, under the riprap layer. A filter cloth (geotextile) or filter layer should be placed under the riprap if there is no bedding layer.
What size is number 2 rip riprap?
The most commonly used sizes of rip rap are Grade 1 (12”-18”) and Grade 2 (18”-24”).
How is rip rap size determined?
Multiply the d50 for straight channels by the bend factor to determine riprap size to be used in bends. If the d50 for the bend is less than 1.1 times the d50 for the straight channel, then the size for straight channel may be used in the bend; otherwise, the larger stone size calculated for the bend shall be used.
What does 1 ton of rip rap look like?
Rip rap can vary in size from about the size of a softball to as large as approximately 10″ to 12″ in diameter. The average is usually from about 3″ to 8″ in size. One ton of rip rap will usually cover an area of 35 to 40 linear feet, spread 3′ wide.
What size is Type 3 rip rap?
Following are the most used sizes: Class I – 50 lbs to 150 lbs. or 12”- 18” Class II – 150 lbs to 500 lbs. or 18” – 26” Class III – 500 lbs. to 1500 lbs. or 26” – 36”
How many tons of rip rap are in a cubic yard?
How many tons of riprap are in one cubic yard? The conversion for riprap varies by size but generally speaking, a conversion of 2 tons per cubic yard is sufficient.
What is riprap gradation?
GRADATIONS. Gradation is the size distribution of a particular riprap or aggregate. Material that is well graded has a uniform distribution of sizes, within a given minimum and maximum range. Void spaces between the larger rock are filled with the smaller material.
