PREDICTION OF CBR USING DCPT TEST RESULTS IN EXCEL 

This module describes how to predict the california bearing ratio of the soil using the Dynamic Cone Penetration test results in the field. The out put of the DCPT test results were fed to the excel file and N value is calculated by dividing the depth of penetration by number of blow. The N value i.e. mm/blow so calculated is being used in the CBR prediction equations given in IRC 37:2012 version, ASTM D 6951 and the equation developed by Kleyn in the year 1975. All the equation had given a resultant CBR value but the results given by the equation given in IRC 37 or ASTM D6951 are more precise and accurate. Once CBR is calculated this value was utilised to predict the ultimate bearing capacity and allowable bearing capacity of the soil. A graph is plotted as the end by using the equation given in IRC and for range of N value from 100 to 2.5 or number of blows 1 to 40 to easily mark the field CBR. This will help the field engineers to quickly get a feel of the CBR of the soil without waiting for a lengthy process of conducting the laboratory CBR and then initiating an action.