Simplified method for nonlinear settlement calculation in soft soils considering lateral deformation

The common method for computing settlement of soft soils is the layer-wise summation method using compression modulus under the confined condition. But the lateral deformation makes a large part of the whole settlement. To eliminate the calculation error, the method in the national specifications or codes is that the results are multiplied by an empirical coefficient from 1.1 to 1.7. Since the empirical coefficient is not sure, a new method considering the lateral deformation is proposed. This method divides the settlement of soft soil into two parts. One is the settlement S_c caused by 1 D confined compression using the layer-wise summation and e-p curve to compute, the other is the settlement S_d caused by lateral deformation using the same way but the parameter is secant modulus E_p from the e-p curve and Duncan-Chang model. So the e-p curve is the core for computing the settlement. In practical engineering, the initial void ratio e₀ and compression modulus E_s1-2 are frequently used and can reflect the characteristics of the soils well. The two parameters are combined with compression index C_c, thus we can use e-lgp curve to get the compression modulus E_si under different stress states. Since E_si, S_c, S_d are easy to get, it brings a big convenience to engineering computation. Finally, the applicability of the proposed method is validated through an engineering case.