The co-seismic landslides and rock avalanches caused by the 2008 Wenchuan earthquake generated numerous poorly consolidated deposits over a vast area. Rainfall-induced initiation and remobilization of these deposits have resulted in many post-earthquake disasters, such as rapid erosion, flow slides, and debris flows, threatening the local residents. The hydraulic properties of the deposits dominate the evolution of the soil moisture in the slope during rainfall, consequently affecting the initiation and failure types of these geo-disasters. Thus, laboratory tests and infiltration experiments were conducted with material from co-seismic landslide deposits in the Wenjia Gully near the Wenchuan earthquake epicentre. The soil-water characteristic curve (SWCC) of the co-seismic deposit material was determined by a pressure plate extractor and tensiometers. Then, a series of large-scale soil column experiments were conducted with the materials. The results of the experiments showed a relatively high permeability and low matric suction of the co-seismic deposit compared with other soils. The infiltration characteristics of the deposit material with different initial water contents, compactness, and fine particle contents were also analysed and compared. A linear solution of the Green and Ampt equation was employed to estimate the infiltration rate in the deposit during rainfall events, which fit the results of the experiments well. The influence of matric suction on the water absorption and retention capacity was obvious when the moisture content was less than 5%, resulting in a variable evaporation rate and a soil-water hysteresis phenomenon. The results of this study provide reliable experimental evidence with which to evaluate the distribution and evolution of soil moisture in landslide deposits, which is significant for geo-hazard assessments and mitigation works.

2008年汶川地震造成的同震滑坡和岩石雪崩在广阔的区域内产生了许多固结不良的沉积物。降雨引起的这些沉积物的萌芽和迁移导致了许多地震后灾难，例如快速侵蚀，泥石流和泥石流，威胁到当地居民。在降雨期间，沉积物的水力特性支配着斜坡中土壤水分的演变，因此影响了这些地质灾害的起因和破坏类型。因此，对汶川地震震中附近的温家沟同震滑坡沉积物的物质进行了实验室测试和入渗实验。同震沉积物的土壤-水特征曲线（SWCC）通过压力板萃取器和张力计确定。然后，对这些材料进行了一系列的大型土柱实验。实验结果表明，与其他土壤相比，同震沉积物具有较高的渗透率和较低的基质吸力。分析并比较了初始含水量，致密性和细颗粒含量不同的沉积物的渗透特性。使用Green和Ampt方程的线性解来估计降雨事件期间矿床中的入渗率，这与实验结果非常吻合。当水分含量小于5％时，基质吸力对吸水和持水能力的影响是明显的，从而导致蒸发速率变化和土壤-水滞后现象。这项研究的结果为评估滑坡沉积物中土壤水分的分布和演变提供了可靠的实验证据，这对地质灾害评估和减灾工作具有重要意义。