USDA soil classification

[ketanco]

not sure who invented that triangle for the USDA soil classification but i still can not figure out how to obtain the result from this graphic, once I have my values. i know it must be simple

 

[icreep]

Go to page 137 of Geotechnical engineering: principles and practices by Coduto (1999 printing)

It has very straightforward explanation of USDA soil classification. To use the chart, you need to know the percentage of sand, silt, and clay in the soil. Plot the three values on the triangle and the intersection of the three lines is your USDA classification.

Also important to note that if the percent passing sieve size #10 is less than 100%, the sample must be normalized.

 

[ptatohed]

http://www.had2know.com/garden/classify-soil-texture-triangle-chart.html

 

[ketanco]

thanks the link really helped. i knew it was easy...