Scour depth calculation of completely weathered rock

[Geosubhtech]

I want to find the silt factor for the calculation of scour depth on completely weathered rock (mica schist). Anyone have any source material or anywhere i an find the literature please inform.

Any source by which new can estimate scour depth for bridge pier foundations especially for completely weathered rock, it will be helpful.
Thank you.

 

[fattdad]

I have no idea what the, "Silt Factor" refers to?

George Annandale has a classification scheme for soil and rock that will return a value for critical stream power - i.e., the stream power that will initiate scour for that material.

Texas A&M have also provided research on the topic of scour. Check out the work of Jean-Louis Briaud.

NCHRP 717 also has information on rock scour.

All of this is great stuff if you actually can develop a design hydrograph. If you don't have a design hydrograph, you may do a great job on your end, but the entire analysis may be ultimately based on the d50 value of the silt, which will return very conservative scour depths!

f-d

ípapß gordo ainÆt no madre flaca!

 

[Geosubhtech]

Thank you.
Silt factor we use for calculation of scour depth by Lacey's method. India we follow this method.