On the Bearing Ability of Paddled Sail to Farm Machineries

Abstract

The behavior of paddled soil under loading plate was examined by model experiment and field survey. In those experiment and survey, circular loading plates, 3 kinds in diameter, with vertical lug along the perimeter, zero to 5cm in height, which cut off the viscous flow of paddled soil, were used.
The settlement at 10 minutes after loading was employed, to inspect a conventional allowable bearing ability. Kurdümoff effect was observed even when the soil possessed the flowing consistency, especially this was evident as the height of the lug was sufficient.
The higher the height of lug was, and the larger the ratio of the perimeter to the area was, the more the allowable bearing ability for a given settlement became.
If the lug should be used in a suitable method, and if the ratio of the perimeter to the area be made should as large as possible, it may be accomplished to make the settlement smaller under the same pressure.
The yield point of paddled soil was not observed evidently, however, the allowable bearing abiltity of this kind mightt be determined as 0.005 to 0.02kg/cm² at the settlement of about 1cm.
These figures fit to the observed value of ground pressure of farm machinery which were manufactured by experience and used on the padded field today.
When the machinery used on the paddled field are to be designed, it is supposed to be suitable to employ the 0.005-0.01kg/cm² as the ground pressure considering the factor of safety of paddled soil.