| Investigations to correlate various rheological parameters as Bingham
yield stress, thixotropic break-down at upper plastic limit consistency,
cation exchange capacity, liquid limit with specific surface area
(SSA) of some Indian red, black and alluvial soils have been reported.
A linear relationship between liquid limit/cation exchange capacity
and specific surface area was noted. The plot between the ratio of
plastic index (PI) and specific surface area (SSA) against Bingham
yield stress or liquid limit yielded three linear curves which indicate
the texture, CH, CL and CL-ML group, of soils. The Bingham
yield stress decreased while the liquid limit increased with increasing
ratios of PI/SSA. The two curves of identical slopes representing
CH and CL group of soils were characteristic of (1) plastic soils
having liquid limit above 50, containing expanding group of clay
minerals and (2) lean plastic soils of liquid limit below SO, containing
a mixture of kaolinite and mica group of clay minerals. |
