Investigation of Water and Soil Migration and Mud Pumping of Subgrades under Traffic Load

Atmospheric precipitation leads to the increase of moisture in subgrade. The and soil migration subgrade is a key scientific problem evaluating service performance resolving or preventing mud pumping. Using self-developed testing system as well numerical simulation model, detailed study dynamic hydraulic characteristics, water mechanism, fine pumping properties was conducted. results showed that migrated into upper layer under traffic load. Meanwhile, pressure gradient for pore generated This kind beneficial migration. With rising groundwater level increasing load, porosity differs at different depths. caused by migration, which causes new channel Then, circulating formed After that, nearly saturated action liquefies instantaneously, becoming mud, However, loading time progresses, continue migrate upward, resulting being pumped ballast gradual disappearance liquefied soils