河川堤防の透気・防水性シート敷設による間隙空気噴発の抑制効果

抄録

It has been pointed out that the pore-air blows off from the surface of river dike during heavy rainfall. It is therefore important to consider the influence of the pore-air blow on the stability of the dike. Based on the laboratory water infiltration experiment in the unsaturated soil column, we found that the pore-air pressure in the soil was generated by the seepage of the water when the air permeability at near the surface was reduced by the rainfall. The pore-air blow occurred due to the larger pore-air pressure. In this paper, the effectiveness of the breathable-waterproof geotextile on prevention of the pore-air blow is experimentally examined. As a result, it is shown that the pore-air blow is prevented in while keeping the air permeability at near the surface by laying the geotextile at the ground surface.