由于废弃的粉质黏土对土地浪费和污染有不利，所以对粉质黏土改良后用于工程建设回填。对浙江省杭州市一沿江隧道开挖产生的粉质黏土添加不同固化剂后进行无侧限抗压强度实验，研究了不同木质素纤维掺量，水泥掺量对无侧限抗压强度的影响，同时对抗压强度形成的机理进行了分析；最后通过SEM实验对试样进行孔隙微观结构的定量分析。结果显示：在木质素纤维掺量为4%时抗压强度达到最大值，并且在木质素纤维掺量为2%、6%、8%时，无侧限抗压强度均大于木质素纤维掺量为0的试样。无论木质素纤维掺量为多少，无侧限抗压强度均随着水泥掺量的增加而逐渐增加。孔隙的平均直径随着木质素纤维的掺入而逐渐集中向粒径小于1 μm范围内，随着水泥掺量的增加孔隙1~2 μm和2~4 μm所占比例增加；孔隙的丰度随着木质素纤维及水泥掺量的增加，主要集中在0.2~0.5。颗粒的丰度随着木质素纤维的掺入，主要集中在0.1~0.6，随着水泥掺入颗粒分布呈现山字形。

Due to the negative impact of abandoned powdered clay on land waste and pollution, it is beneficial to improve the powdered clay and use it for backfill in engineering construction. The effects of lignin fiber content and cement content on the unconfined compressive strength of silty clay excavated from a tunnel along the Yangtze River in Hangzhou, Zhejiang Province were studied. The formation mechanism of the compressive strength was analyzed. Finally, the pore microstructure of the sample was quantitatively analyzed by SEM experiment. The results show that the compressive strength reached the maximum value when the lignin fiber content is 4%, and the unconfined compressive strength was greater than that when the lignin fiber content is 2%, 6% and 8%. No matter how much lignin fiber content is, the unconfined compressive strength increases gradually with the increase of cement content. With the addition of lignin fiber, the average diameter of pores gradually concentrated in the range of particle size less than 1 μm, and the proportion of pores 1 ~2 μm and 2 ~4 μm increased with the increase of cement content. With the increase of lignin fiber and cement content, pore abundance mainly concentrated in the range of 0.2 ~ 0.5. With the addition of lignin fiber, the particle abundance mainly concentrated in the range of 0.1 ~ 0.6, and the particle distribution showed a "mountain" pattern with the addition of cement.