Abstract
A series of physical property aud chemical composition tests were conducted on ten fall loam soils, two secondary sedimented loam soils and two alluvial clays, all of which were obtained throughout Aomori Prefecture. Mechanical strength tests were also done for undisturbed and compacted samples of the soils. The main findings were as follows : (1) Silt fractions are what mostly control the in-situ moisture contents which are closely related to the amorphous contents of the fall loam soils; (2) The fall loam soils were categorized into the amorphous rich and the amorphous somewhat high fall loams by an in-situ moisture content of 70%. The amorphous rich loams showed unusual characteristics; (3) The strength of the undisturbed samples increases with an increasing in-situ moisture content for amorphous rich fall loam soils, but decreases for amorphous somewhat high fall loam soils; (4) The strength loss due to remoulding and the strength itself of the compacted samples were uniquely expressed by the liquidity index; (5) The ratio of CBR(compacted sample)/CBR(undisturbed sample) for amorphous rich fall loams becomes higher when the liquidity index increases. Finally, a practical classification chart consisting of the in-situ moisture content and the liquidity index, with two special lines, (Wn=70% and IL=0.8), was proposed.
