Issue 7

Abdoullah Namdar et alii, Frattura ed Integrità Strutturale, 7 (2009) 73-79; DOI: 10.3221/IGF-ESIS.07.06

q f

= 1.3C N c

+ γD N q

+ 0.4 γB N γ

(1)

q nf

= q f

- q nf

= q f

- γD

(2)

q s

=(q nf

/ F)+ γD

(3)

Also N q

, N c

and N γ

are the general bearing capacity factors and depending upon

1) Depth of footing; 2) Shape of footing; 3) Φ, friction angle. These parameters have been used from suggestion by the Terzaghi calculation method [3].

R ESULT AND DISCUSSION n order to determine soil morphological characteristics, wet sieve analysis has been employed. Morphology of seven soils have been used in developing models, as shown in Tab. 2 and Fig. 1. Among all soils, red and black soils have the most linear distribution of particles. Tests of liquid limit and plastic limit, indicated that black green, yellow, dark brown and light brown soils are not plastic soils, and only red soil is a plastic one. Results of liquid limit and plastic limit are mentioned in Tab. 3, 4 and Fig. 2. Red soil has liquid limit of 32.7% and plastic limit of 17.785%. Red soil has been selected for evaluation of its characteristics because of its plasticity. This will allow the eventual improvement of red soil as a construction and sub soil material. I

COF Dark Brown Soil 99.59 89.10 50.15 36.23 33.40 22.10 16.45 14.84 11.61

COF Light Brown Soil

COF Red Soil 99.58 94.16 88.12 86.24 71.24 61.86 58.94 55.40 100

COF Yellow Soil

COF Green Soil

COF Black Soil 96.94 91.83 83.66 80.59 78.55 67.52 60.77 56.88 52.19

Sl. No

Diameter of Sieve

COF Sand

1 2 3 4 5 6 7 8 9

4.75

100

100 99.6 98.6 98.2 93.8 86.8 75.2 99

100 99.6 99.4 98.8 98.2 97.6 99

100 92.6 63.2 59.6 48.2 40.4 34.6 31.6 73

2 1

96

79.8 63.2 50.6

0.6

0.425

0.3

7.6 2.8 1.8 1.2

0.212 0.150 0.075

97

68

95.2

10

Received

0

0

0

0

0

0

0

Table 2 : Result of sieve analysis of soils (COF=Community Passing Finer).

Figure 1 : Result of soils sieve analysis.

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