TIME DEPENDENT FIELD CBR AND ITS REGRESSION MODEL

In the present paper a series of California Bearing Ratio (CBR) tests has been performed in both soaked and unsoaked condition on field samples collected from road subgrade. Four rural roads in West Bengal, India have been considered for collection of field CBR sample. From the experimental data it is found that with time the values of CBR in soaked and unsoaked condition increases irrespective of types of road subgrade. Based on the present experimental data a nonlinear power model has been developed to predict field soaked CBR value with time (CBRfst), in terms of field soaked CBR value at 0 days (CBRfs0 ) and time ‘t'.