PSI - Issue 33

Anas Ibraheem et al. / Procedia Structural Integrity 33 (2021) 942–953 Anas Ibraheem, Yulia Pronina / Structural Integrity Procedia 00 (2019) 000–000

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To compare the methods, we calculated the ratio (R) shown in Table 2, where R � ��������������������������������������������������������������� ���������������������������������������������������������������� Table 2. R values calculated for each soil pattern and footing type Soil pattern Footing type Type 1 Type 2 Type 3 Silty sand 1.31 1.34 1.36 Loose sand 1.30 1.33 1.36 Medium dense sand 1.28 1.30 1.33 Sand and gravel 1.27 1.30 1.33 Dense sand 1.23 1.25 1.28 Soft clay 0.5 1.17 1.23 1.30 Medium clay 0.5 1.15 1.21 1.28 Stiff clay 0.5 1.14 1.20 1.27

From Table 2 it can be concluded that:  The solution using the first method gives greater values in the elastic settlements compared to the second method.  The larger the dimensions of the foundation, the greater the ratio R.  The higher the elastic modulus of the soil, the lower the ratio R.  The higher the Poisson’s ratio of the soil, the lower the ratio R.  The increasing rate of the ratio R is greater when calculating the settlements in clay soils (according to the relationships of settlement of shallow foundations in cohesive soils (this is evident in Fig. 5)).

Fig. 5. The change of the ratio R according to soil pattern and footing type.

The new method allows introducing the effect of consolidation settlement in clay soils, which greatly affects the results of the analysis and design. We performed the analysis of the model of the building considered above, using soil pattern (sutured medium clay) with these properties: weight per unit volume is 17 kN/m 3 , modulus of elasticity