Apart
from standard physical property tests, such Atterberg limits,
gradation curve etc., the governing test for design has
to be CBR test. To measure the increase in CBR value due
to CON-AID
treatment, it is necessary to conduct the CBR test at the
expected equilibrium water content, that is, the sample
should be tested at approximately 50% of the optimum water
content since the special tests have clearly indicated the
magnitude of reduction in the water content.
Although different soil compositions may give variation
in reduction factor, pressure plate tests could be conducted
to measure this value before applying the factor to the
tested soils. In the guidelines prepared by the Transport
Research Laboratory (TRL), there are some recommendations
on designing pavement based on expected capillary level
in the pavement structure; in other words, laboratory tests
should be performed according to the actual field condition
with respect to the reduction in water content after treatment.
It is concluded that conventional way of determining the
CBR values under soaked condition will not be an appropriate
testing method for this type of soil stabilizer because
the stabilizer is recommended to be applied to soil above
groundwater table only.
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