Fundamental Studies on Tillage Machinery (IV)

Experimental Method on the Effects of Shape & Mechanism Factors of Tillage Devices upon the Soil Stress and Resistance Force Components

Abstract

The main aims of these experiments are, firstly to clarify the effects of the factors concerning mechanism of tillage devices and shape of their blades upon the soil stress distribution as well as the resistance force, and secondary to verify the stress theory which the author mentioned before.
As the shape factors, discontinuity of cutting plane, curvature of blades and cutting angle are taken up. As the mechanism factors, velocity and degree of freedom of motion are picked up. Several kinds of model blades with different shape factors have been made.
A series of experiments are carried out using soil bin test devices. After the preparation of soil in uniform condition, D-18 Type Micro Soil Stress Meters are buried in the 12 points of furrow slice cross section. The direction of Stress Meters is also varied in 0, 45 and 90 degrees. Then, stress analysis is carried out, and the stress distribution in furrow slice, special soil stress indexes and stress of plane of soil failure are obtained. Three resistance force components are measured also and investigated.