Internal Friction angle for riprap
Internal Friction angle for riprap
(OP)
hi, I am trying to find a manual or any article referring to the internal friction angle or slope angle for a riprap covering made with rocks greater than 80 cm for protecting the natural river alluvium hill from the flooed of the river. I think a slope of 1.5H:1V is appropriate, but I have to confirm this.





RE: Internal Friction angle for riprap
From
http://huron.lre.usace.army.mil/coastal/LMPDS/documents.htm
document pdf
http://huron.lre.usace.army.mil/coastal/LMPDS/Downloads/shorepimpacts.pdf
gives for lake coast use 2 examples 3:1V and 4:1V less steeper then than your proposal. Obviously duration may be very relevant to the choice.
In the more general search
http://www.google.com/search?q=rip-rap+%22friction+angle%22&hl=es&btnG=B%FAsqueda+en+Google&lr=
you should find better assessment.
RE: Internal Friction angle for riprap
Chuck
cgopperton@stantec.com
http://www.stantec.com/
RE: Internal Friction angle for riprap
RE: Internal Friction angle for riprap
However, if you are simply trying to perform a static stability analyses of a 1.5:1 (H:V) rock slope that has good interlocking using rough quarry stone, then you can easily use values of 40 to 45 degrees. Hence, the factor of safety for your slope would be about 1.25 to 1.5 depending the overall design and quality of construction. Nevertheless, riprap is often placed at 1.5:1 without any problems if nothing else happens. The thickness, toe burial, crest width, underlayer design, water conditions, etc. will control the design.
Good luck.
Moi Arzamendi, PE
LKS Ingeniería, S. Coop.
Arrasate 20550, España