The Kanto Loam volcanic ash soil has abnormal engineering properties. Compared with non-volcanic ash soil, earth moving and compaction of the KantO Loam is more difficult. The authors investigated the relationships between the soil condition and the traction performance of tractors in the field and in the laboratory.
Results are as follows:-
1. The strength of the KantO Loam is decreased extremely by disturbance, which inevitably results in the decrease of the traction performance of tractors.
2. The mechanism of generating the power of traction is clarified.
3. The compaction of the fill up ground of the Kanto Loam is very difficult. This fact should be considered in planning the earth moving.
4. The engineering properties of soil are closely related to the history of the soil formation. We must create the field of the engineering pedology for the improvement of the earth work.
