The strength recovery (healing) of the shear zone soil of a landslide during the dormant phase after the sliding affects the reactivation of the landslide, and may play a key role in determining the stability of the landslide. In this paper, we report the laboratory measurements of frictional strengthening characteristics of a red-bed landslide soil. Slide-hold-slide (SHS) experiments and ultrasonic tests are performed on soil samples under natural moisture content and saturated conditions. The roles of holding time, normal stress, and drainage conditions in friction enhancement are evaluated. All the experiments are performed under room temperature. The saturated soil samples show the lowest recovery value of shear strength. It is found that red-bed landslides have obvious healing properties. The recovery value log-linear depends on the holding time and proportional to the normal stress, and the better the drainage condition is, the more obvious the recovery. Ultrasonic tests show that the wave speed difference of soil sample before and after holding is proportional to the holding time.

滑移后的休眠期滑坡剪切带土的强度恢复（恢复）影响滑坡的再活化，并可能在确定滑坡的稳定性方面起关键作用。在本文中，我们报告了红层滑坡土的摩擦强化特性的实验室测量结果。在自然水分含量和饱和条件下，对土壤样品进行了滑动-保持-滑动（SHS）实验和超声测试。评估了保持时间，法向应力和排水条件在摩擦增强中的作用。所有实验均在室温下进行。饱和土壤样品的剪切强度恢复值最低。发现红层滑坡具有明显的愈合作用。恢复值的对数线性关系取决于保持时间并与法向应力成正比，排水条件越好，恢复效果越明显。超声波测试表明，保持前后土壤样品的波速差与保持时间成正比。