Evaluation of Moraine Loams' Filtration Properties

Abstract

In Lithuania, surface moraine loam, clay and other lithologic varieties with low permeability take around 60% of the territory. Roads, railway tracks, bridges, dumps intended for keeping waste of different level of danger and other overground structures are built in these areas. Moraine formations with low water permeability become the foundation for earth bank, roads, bridge supports, dumps and other engineering structures. Through these foundations water filtration, infiltration, movement of capillary water and evaporation to the atmosphere continue during the entire period of operation. In wintertime, the volumetric changes of water, contained and freezing in these soils, and water migration in soil towards the surface of freezing determine deformations of foundations or road surface and the occurrence of frost cracks. All the mentioned water migration processes in the layers take place in various directions and in different intensity. This determines the change in geomechanical and geofiltration properties of foundation soils. Foundation soil deformations are likely also due to the processes of drying, bloating and filtration of clayey soils. Thus, the goal of the present work is to evaluate the evolution of filtration features and evaporation intensity of moraine loam in time. The continuous duration of laboratory investigations was over 10 months. For filtration, the filtrometer was used containing the Proctor Standard moulds, water deaeration device and pressure measuring stand with three tubes of different diameter (piezometers). Water and air temperature and relative humidity of the laboratory were measured during each experiment.