THE PHYSICO-CHEMICAL PARAMETERS RESPONSIBLE FOR ROAD FAILURES IN SOUTHERN NIGERIA
Geotechnical tests were carried out, these include, Atterberg test, particle size, compaction test and plasticity index. Sieve analysis showed that the soils from this zone are within the medium to coarse grain range with low percentages of silt/clay, therefore the soil is non plastic. The compaction tests also showed that the optimum moisture content ranges from 13.50% to 15.20% while the maximum dry density ranges from 1.75mg/m3 to 1.98mg/m3. The plasticity index revealed that the soils are non-cohesive and non-plastic because it ranged from 1.2% to 5-2%. The maximum dry density values are generally low which indicated that the soil is not compact but loose.
There were presences of pockets of smectitic clay with high montmorillonite content. This has the most swelling potentials and accounts for the most of the damages resulting from expansive clays.