Chef de projet : NOM Prnom - Repositório Aberto da Universidade ...

Premier Symposium Méditerranéen de Géoengineering «SMGE09» Alger 20 et 21 juin 2009
Figure 2. Mesh used – structure 1 (A2).
Calculation of the deformation modulus based on the numerical analysis
First of all, it should be highlighted that a significant variability was obtained in the in situ
displacements measured by geophones on the different test points. The calculation of the
deformation modulus was done based on results obtained from the first height impact, i.e., for a
peak load of approximately 20 kN.
Initially, an attempt was made to find the deformation modulus of both the subgrade and the
bottom capping layer, in order to determine the outer part of the deflection basin (the most
distant from the load application place). For this purpose, the deformation modulus of the
treated soils was fixed on 200 MPa and the deformation modulus of the subgrade and of the
untreated soil (indicated as “soil”) varied as showed in Table 2.
Table 2. Hypotheses considered for the deformation modulus of the subgrade and untreated soil.
E treated
Deflections [μm]
E soil E
Hypothesis
subgrade
soil
Df1 Df2 Df3 Df4 Df5 Df6 Df7 Df8 Df9
[MPa] 0 30 45 60 90 120 150 180 210
1 50 80 434 218 144 99 55 35 25 19 16
2 60 80 423 210 140 98 55 36 26 20 16
3 80 100 372 170 111 77 44 29 21 16 13
4 80 120 348 149 94 64 35 23 17 13 10
200
5 60 140 346 143 85 55 29 19 14 11 9
6 80 160 317 122 72 47 26 17 13 10 8
7 100 170 300 111 66 43 24 16 12 9 7
8
120 170 292 107 64 43 25 17 12 9 7
The minimum and maximum deflection basins indicated in Figure 3, correspond to the minimum
and maximum displacements measured by geophones. Hence, the minimum basin corresponds
to the structure with the best mechanical characteristics and the maximum basin corresponds to
the structure with the worst mechanical characteristics.