利用全自动三轴仪进行了南京及附近地区粉土、粉质粘土、粘土的不排水剪切试验,研究剪切带倾角随围压和含水量之间的变化规律,比较Mohr Coulomb理论、Roscoe理论和Arthur理论对剪切带倾角的预估.试验表明轴对称条件下,粉土样剪切带倾角随着围压的增高而增大,含水量对粉土样剪切带倾角的影响不大.在相同围压的情况下,松散试样的剪切带倾角略高于密实试样的剪切带倾角.粉质粘土、粘土样的剪切带倾角随着含水量的增加而降低.Mohr Coulomb理论计算得到的剪切带倾角与试验实测值较接近. The undrained shear tests of silt, silty clay and clay in Nanjing and its surroundings were carried out by means of a fully automatic triaxial apparatus. The variation of shear band inclination with the confining pressure and water content was studied. According to Mohr Coulomb theory, Roscoe Theory and Arthur’s theory.Experiments show that under the axisymmetric conditions, the dip of silty shear zone increases with the increase of confining pressure, and the effect of water content on the dip of silty shear zone is not affected In the same confining pressure, the inclination of the shear band of the loose specimen is slightly higher than that of the dense specimen.The inclination of silty clay and clay-like shear zone decreases with the increase of water content. The shear band inclination calculated by Mohr Coulomb theory is close to the experimental value.