Question

CE 366 Introduction to Soil Engineering Extra Credit Homework #3 Due 30 November 2018 1. Classify Soils A C, E using the Unied Soil Classification Systerm #200 0.075mm 3 in 76.2mm 4.75 mm 100 90 面70 50 40 30 20 10 0.001 0.01 0.1 10 100 Grain Size (mm) Soil A -Soil B -Sol C -Sol D -Sol E Soil A 13 Soil B 35

Answer 1

Q 1: Soil A - poorly graded soil , Soil C- well graded soil , Soil E - gap graded soil

Q 2 compaction curves for all soil are given below

(c) Degree of saturation at OMC for column A. w = OMC = 12.5 % r_d = 18.7 kN/m^3 G = 2.64 r_w = 9.81 kN/m^3. r_d = r_w G /1 + e 18.7 = 9.81 * 2.64 /1 + e e = 0.384 For degree of saturation = (S_r): w_G = S_r middot e 12.5/100 * 2.64 = S_r * 0.384 S_r = 0.859 S_r = 85.93 %

b: MDD and OMC are given below MDD=maximum dry density OMC= Omptimum moisture content

Soil A - OMC= 12.5 % and MDD= 18.7 kN/m³

Soil B- OMC= 15 % and MDD= 17.22 kN/m³

Soil C - OMC= 17% and MDD= 17.12 kN/m³