Atterberg Limits Formula PDF

Preview

Summary

Notes...

Description

Atterberg Limit Tests 1.) Liquid limit Tests 2.) Plastic limit test 3.) Shrinkage limit test

Plasticity Index Plasticity Index = liquid limit – plastic limit PI = LL - PL P.I. = plasticity index L.L. = liquid limit P.L. = plastic limit

Liquidity Index 𝐿. 𝐼. = where : L.I. = liquidity index 𝜔 = in sity moisture content of soil P.L. = plastic limit L.L. = liquid limit Characteristic of Soil : When L.I. < 0 - brittle solid When L.I. < 1 - plastic

𝜔 − 𝑃𝐿 𝐿𝐿 − 𝑃𝐿

When L.I. > 1 – liquid

Consistency Index 𝐶. 𝐼. = C.I. = consistency index L.L. = liquid limit 𝜔 = moisture content P.I. = plasticity index

Flow Index (lf) 𝒍𝒇 =

𝐿. 𝐿. − 𝜔 𝐿. 𝐿. − 𝑃. 𝐼,

𝝎𝟏 − 𝝎𝟐 𝑵 𝒍𝒐𝒈 ( 𝑾𝟐 ) 𝟏

𝝎𝟏=𝑚𝑜𝑖𝑠𝑡𝑢𝑟𝑒 𝑐𝑜𝑛𝑡𝑒𝑛𝑡 𝑜𝑓 𝑠𝑜𝑖𝑙,𝑖𝑛 𝑝𝑒𝑟𝑐𝑒𝑛𝑡,𝑐𝑜𝑟𝑟𝑒𝑠𝑝𝑜𝑛𝑑𝑖𝑛𝑔 𝑡𝑜 𝑁1 𝑏𝑙𝑜𝑤𝑠

𝝎1 = 𝑚𝑜𝑖𝑠𝑡𝑢𝑟𝑒 𝑐𝑜𝑛𝑡𝑒𝑛𝑡 𝑐𝑜𝑟𝑟𝑒𝑠𝑝𝑜𝑛𝑑𝑖𝑛𝑔 𝑡𝑜 𝑁2 𝑏𝑙𝑜𝑤𝑠

Toughness Index 𝑻𝒐𝒖𝒈𝒉𝒏𝒆𝒔𝒔 𝒊𝒏𝒅𝒆𝒙 =

Shrinkage Limit 𝑆. 𝐿. =

𝑷𝒍𝒂𝒔𝒕𝒊𝒄𝒊𝒕𝒚 𝒊𝒏𝒅𝒆𝒙 𝑭𝒍𝒐𝒘 𝒊𝒏𝒅𝒆𝒙

(𝑚1 − 𝑚2 ) (𝑉1 − 𝑉2 ) 100 − 𝑃𝑤 (100) 𝑚2 𝑚2

SL = shrinkage limit M1 = mass of wet soil in the dish in grams M2 = mass of dry soil in the dish in grams V1 = initial vol. of wet soil in the dish V2 = final vol. of dry soil in the dish in cc 𝜌𝑤 = density of water (1 gr/𝑐𝑚3 )

Shrinkage Ratio 𝑆𝑅 = SR = shrinkage ratio M2 = mass of dry soil in the dish in grams V2 = final vol. of dry soil in the dish in cc 𝜌𝑊 = density of water (1 gr/𝑐𝑚3 )

𝑀2 𝑉2 𝜌𝑊

Specific gravity

𝐺𝑆 = Gs = specific gravity SR = shrinkage ratio SL = shrinkage limit

1 1 𝑆𝐿 − 100 𝑆𝑅...