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Résumé :
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Elastoplastic finite element analyses were performed to determine the effects of elastic anisotropy on surface settlements caused by a uniform surface loading and by tunnelling. For typical ranges of elastic cross-anisotropic parameters, the effect of anisotropy on settlement induced by surface loading is modest; however, for the case of tunnelling, the effect of elastic anisotropy, in particular the ratio of the independent shear modulus G vh, to vertical modulus E v, should be considered if reasonable predictions of settlement are to be obtained. The practical implications of these find- ings are shown by considering the centrifugal model tunnel tests conducted at Cambridge University. It is found that the anisotropy has a significant effect on the shape of the settlement trough and that reasonable agreement between observa-tion and theory is obtained for G vh/E v, of between 0·2 and O·25, which is smaller thanthe isotropic value of G vh/E v, = 0·33 (for the undrained condition). The reasons for this are discussed.
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