[Objective] To investigate the influence of compactness on water transport characteristics of iron tailings sand

in order to provide scientific support for soil and water conservation and vegetation restoration in iron mining area. [Methods] The infiltration process and water characteristic curves were measured by means of one-dimensional soil column test and tensometer method at five bulk weight levels of 1.50

1.55

1.60

1.65 g/cm3 and 1.70 g/cm3. [Results] ① As the bulk density increased

the infiltration capacity of iron tailings decreased

and the bulk density had a significant linear negative correlation with the stability of the iron tailings

the cumulative infiltration and the wetting peak distance (p<0.05). ② The water content of the tailings of 1.50~1.60 g/cm3 was obviously stratified with depths

and the water content of the tailings sands of 1.65 g/cm3 and 1.70 g/cm3 was less. ③ The correlation coefficient between the saturated hydraulic conductivity of the iron tailings and the measured value of the Green-Ampt model was 0.886

and the calculation accuracy was high. The Kostiakov model was the best for fitting the different weight-bearing iron tailings infiltration process (R2=0.989). ④ During the dehumidification process

the water holding capacity drop significantly at levels of high bulk density made. The water holding and water retention performance was the best at levels of 1.60 g/cm3. The water characteristic curve fitted with van Genuchten model showed that the saturated water content

residual moisture content

air intake value and shape coefficient decreased with the increase of bulk density. [Conclusion] High compactness seriously inhibited water infiltration and water holding capacity of iron tailings. Loosing tailings matrix should be used to improve the structural properties in the reclamation.