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Thermohydromechanical behaviour of soils and soil structure interfaces 241

Figure 5.26 Influence of temperature on the angle of shear strength under constant volume condi-
tions. Redrawn after Yavari, N., Tang, A.M., Pereira, J.-M., Hassen, G., 2016. Effect of temperature on
the shear strength of soils and the soil structure interface. Can. Geotech. J. 53 (999), 1 9.

5.6.4 Temperature effect on critical state line
Studies on the sensitivity to temperature of the slope of the CSL have been presented
for example by Hueckel et al. (2009, 2011). Accordingly, the apparent preconsolida-
tion pressure is not the only yield locus characteristic that may evolve with tempera-
ture. The slope of the CLS, similar to the angle of shear strength of soils, may exhibit
a slight dependence on temperature. According to Hueckel et al. (2009), this tempera-
ture dependence is most likely material specific. The considered result has been veri-
fied, for example by Cekerevac and Laloui (2004) considering the results of shear tests

on soil samples tested at temperatures of 22 C and 90 C. Fig. 5.27 presents the con-
sidered results in the semi-logarithmic plane of void ratio—mean effective stress. The
slope of the CSL obtained at temperatures of 22 C and 90 C, which are expressed in

terms of the compression index read C c 5 0.181 (at 22 C, based on 11 tests) and

C c 5 0.185 (at 90 C, based on seven tests). Despite the actual differences between the
results, a negligible influence of temperature on the slope of the CLS can be consid-
ered due to the significance involved. Fig. 5.28 presents additional results that corrob-
orate the previous consideration in the p 2 q plane, with reference to the critical state
0
parameter, M c . The insensitivity of the CLS to temperature agrees with the corre-
sponding insensitivity of the angle of shear strength under constant volume conditions
observed in this case.

5.6.5 Temperature effect on consolidation parameters

The primary consolidation coefficient, c v , is typically found to increase with tempera-
ture due to the reduction of water viscosity (Towhata et al., 1993; Delage et al., 2000;