a Division of Agricultural and Food Engineering, Asian Institute of Technology, Bangkok, Thailand
b USDA Midwest Area National Soil Tilth Laboratory, 2150 Pammel Drive, Ames, Iowa 50011, U.S.A.
Abstract:
Experiments in wet clay soil with cage wheel lug showed that the failure pattern in front of a lug was totally different from that assumed in passive soil pressure theory. Based on the failure pattern, the area of deformation zone and surcharge buildup in front of the lug, it was observed that the existing passive soil pressure theory could not be used to describe the soil movement caused by the action of the cage wheel lug. While working with a tine, four types of soil failure patterns were observed. It was found that these types of soil failures in front of a rigid tine were a strong function of soil moisture content. Passive pressure theory does not accurately predict the forces measured.