Question

Q2. A sample of soil was tested in the laboratory with the following results: Soil LL PI 1 inch 3/4 inch 1/2 inch No.4 Sieve analysis, percent finer No. 10 No. 20 No.40 No. 60 63 21 15 10 No. 100 No. 200 A 100 100 100 90 8 6 NP B 100 85 70 51 50 45 28 18 14 9 40 28 с 100 100 100 98 92 88 83 78 73 49 63 Classify the soils using the Unified Soil Classification and Symbol (USCS) Chart.

Answer 1

? Soil. A LL = -, P1 = NP % finer Sieve size Cmm 25.4mm 100 19.0 mm 100 12.7 mm 100 4.76mm 90 2.0mm 63 0.841 mm 21 0.420 mm 15 0.250 mm 10. 8 0.149 mm 6 0.074 mm . Here (100-694% ie more than 50% 28 retaeried on No: 200 sieve C0.074mm), so it is Coogse grained soil. (600-90) 39 10%. retained on 4.76 mm) 50% 091 more Ús retained on No: 200 sieve (94-10) it is termed as e and 84% (5) CS Scanned with CamScanner

100+ 908 80 + finer CN) pencentage 70 60 Dio = 0.25 mm D20 0.9 mm 50 Doo = 3.0mm HO 30 = 12 20 Cu=D60 DIO Cc Doox Dio = (D30)² = 1.08 10 에 0-29 0.01 odha 1.0 3.0 40.0. 0.1 10.0 particle size (mm) — CS Scanned with CamScanner

For sand, uniformity and coefficient graded sand coefficient (u gbon mone is well curvature (6) lies between 1 and3 => well 6. According to uscs chart, soil A is g graded SW Soil B % finer sieve size mm) 25.4 100 19.0 85 12:7 70 WL = 40% 4.76 51 PI 28 % 2.0 50 0.84) 45 0.42 28 18 0.25 14 0.149 o (0.074 Again more than 50% (100-9) 91% is refained on No. 200 sieve (or coarse grained soen CS Scanned with CamScanner

So renaining g larger 91% a course fraction out of this 49% is grefarried on (4.76 mm) = 100-57 (91-49) = 12% refained on No:200 sieve .. more than half coarse fraction is refuessed on than 4.75 mm , the soil is graves The song has more than 12% fines ie we=40% Here Allesberg limits plot above A line W L=40% and PI = 28% so it clay Awarding USC charl, soil B is GC soilc is Sieve size cmm % finer 25.4 100 19.0 100 12:7 100 4.76 W = 63 98 92 2-0 PI = 6 0.841 88 6.42 83 0:25 78 73 0.149 0.074 49 CS Scanned with CamScanner

Here 100-49 → 51 % retained on 0.074 mm sieve .. coapse grained sord 9 graves out this course foraclion, 2% nefaersed on 4.76 mm fraction 49% + (51-2) z sand frac Pion. WL=63 is the soil has more than 12% fines % Here soil is sand. WL=63 and Plz 6 plots below A line (it can be MH according to uscs chart soil C is SM CS Scanned with CamScanner