Abstract: Aiming at the investigation of partial soil drainage under loading conditions of engineering projects in loess areas, we conduct triaxial tests of saturated loess samples using a muti-functional GDS stress path triaxial apparatus, and examine the strength of saturated remolded loess under different drainage conditions. Results show that as the strain increment ratio increases, the strength increases while the excess pore water pressure generated through shearing decreases. The influence of partial drainage on soil strength is in two aspects: one is that the load condition, or the effective stress path of soil, makes the loading mode of drainage different from that of water absorption; the other is the soil property, i.e., the volume deformation characteristics influence the development of shear dilatation and thereby affects the internal friction angle of soil so that finally the soil develops into an asymptotic state. Based on the present experimental data, we analyze the variation trends in stress path and asymptotic state under different drainage conditions, adjust the calculation method of limit stress ratios, and obtain a linear relationship equation of limit stress ratio versus strain increment ratio of saturated remolded loess.

Key words: saturated loess, partial drainage, strength characteristics, asymptotic state