Question

the calculations should be far enough so that the utlimate settlement at this distance is negligible. Layer Initial Void Elevation (m bgs) 0-1 1-4 4-6 Ratioe. Table 2. Properties of Layers A, B, and C. Total Unit Wt. OCR Swelling Compression (kN/m) Index Cs Index Cc 15.3 15.1 0.008 0.04 17.8 4.3 0.012 0.084 19.4 0.010 0.50 в 0.53 0.47 0.43

Answer 1

5m 3m A layer B layer Clayer

The ultimate settlement of the clay layer can be calculated by using the formula,

AH = H, * Ce* log(01/06)/(1+eo)

where,

H_o = Thickness of soil stratum or layer

Cc - Compression index

e_o - Initial void ratio

Final stress = Initial stress + Incremental stress

of = 0 + Ao

Initial stress = Bulk unit weight of the soil * Depth of soil layer

Incremental stress is calculated by Bousinessq's equation,

Ao = 3 *Q* (1/(1+ (r/-)2))5/2/(2 * II * Zº)

where,

r - Radial distance

Z - Depth of the layer from the bottom surface of the footing

The ultimate settlement is calculated from the centre of the footing to the distance of 6m from the centre.

The values are shown the below table

Depth S.No Radial Distance (m) Load, | Incremental stress, 10. = | Initial layer (kN) 3Q"(1/(1+(r/z)%)32/(2*T*z?) thickness(Ho), mm Compression Initial void index, Cc ratio, e Stress, oo Ultimate Settlement, Su= Ho+Cc+log((0.'+40'/'1/(1+e.) Total settlement, 0.5 2625 5015.92 1000.00 0.04 0.53 7.65 73.66 2625 200.64 3000.00 0.084 0.47 130.58 341.10 2625 50.16 2000.00 0.5 0.43 88.1 136.87 2625 886.70 1000.00 0.04 0.53 7.65 54.06 2625 181.90 3000.00 0.084 0.47 12459 312.80 2625 48.93 2000.00 0.5 L 0.43 88.1 134.15 2625 89.73 1000.00 0.04 0.53 7.65 28.88 25 2625 138.44 3000.00 0.084 0.47 108.53 263.81 2625 45.47 2000.00 0.5 0.43 88.1 126.40

S.No Radial Distance (m) Depth (m) Load, O (kN) Incremental stress, go'= | Initial layer 3Q+(1/(1+(r/2))32/(2*r*z?) thickness(Ho), mm Compression index, Cc Initial void ratio, e. Stress, o Ultimate Settlement, Su= Ho+Cc+log((0.'+46,")/0,"\/(1+e.) Total settlement, mm 05 2625 15.86 1000.00 0.04 0.53 7.65 12.75 2625 93.02 3000.00 0.084 0.47 42 86.94 214.41 2625 40.44 2000.00 0.5 0.43 88.1 114.72 2625 4.21 1000.00 0.04 0.53 7.65 4.98 2625 58.25 3000.00 0.084 0.47 64.77 170.38 2625 34.61 2000.00 0.5 0.43 88.1 100.63 2625 1.46 1000.00 0.04 0.53 7.65 1.98 2625 35.47 3000.00 0.084 0.47 45.58 133.23 2625 28.71 2000.00 0.5 0.43 88.1 85.67

S.No Radial Distance (m) Depth (m) (m) Load, ol Incremental stress, go'= Initial layer (kN) 3Q*(1/(1+(r/z))))32/(2*r*z?) thickness(Ho), mm Compression Initial void index, Cc Stress, Ultimate Settlement, Su = H,+Cc*log((6.'+A6,')/0,')/(1+e.) Total settlement, 0.5 2625 0.60 1000.00 0.04 0.53 7.65 0.86 2625 21.57 3000.00 0.084 0.47 42 30.86 102.86 2625 23.25 2000.00 0.5 0.43 88.1 71.14 2625 0.28 1000.00 0.04 0.53 7.65 0.41 2625 13.31 3000.00 0.084 0.47 20.50 78.82 2625 18.51 2000.00 0.5 0.43 88.1 57.91 2625 0.15 1000.00 0.04 0.53 7.65 0.22 2625 8.39 3000.00 0.084 0.47 13.56 60.24 2625 14.56 2000.00 0.5 0.43 88.1 46.46

اقر 2625 0.08 1000.00 0.04 0.53 7.65 0.12 1 ا اترا 2625 5.42 3000.00 0.084 0.47 9.04 46.05 | القرية 2625 11.38 2000.00 0.5 0.43 88.1 36.90 | 2625 0.05 1000.00 0.04 0.53 7.65 0.07 | 2625 3.59 3000.00 0.084 0.47 6.10 35.30 | 2625 8.87 2000.00 0.5 0.43 88.1 29.12 | اقرة 2625 0.03 1000.00 0.04 0.53 7.65 0.05 | اقرة 2625 2.43 3000.00 0.084 0.47 42 4.19 | الر 2625 2000.00 0.5 0.43 88.1 22.93 2625 0.02 1000.00 0.04 0.53 7.65 0.03 2625 1.69 3000.00 0.084 0.47 42 2.93 21.01

Ultimate Settlement, Radial Distance, m mm 341.10 0.5 312.80 263.81 214.41 170.38 133.23 102.86 78.82 60.24 46.05 35.30 27.17 21.01

Radial distance, Settlement, mm