A series of isotropic consolidated drained true triaxial tests with different Lode angles in the same π plane are carried out with an automatic controlled mixed boundary true triaxial apparatus. The maximum and minor principal stresses are applied by two pairs of rigid platens; and the intermediate principal stress is applied by water pressure in triaxial cell. Undisturbed soil sample is prepared by block sampling method; and totally 5 drained tests with different Lode angles (0°

15°

30°

45°

60°) are presented. Test results show that the shear strength

the yielding & failure points of Shanghai soft clay decrease while Lode angles increase. The volume change increases first and turns to decrease when Lode angle is larger than 30°. In general

three-dimensional strength of the Shanghai soft clay obeys the SMP (spatial mobilized plane) failure criterion.