Interpretation of Compressibility Properties of Soil Surrounding Bored Piles from Pile Load Test Results

Unsatisfactory bored pile may result due to low skin frictional resistance or due to low end bearing resistance. A new methodology is proposed herein to estimate the shear stiffness of the material along the pile shaft using the static load - settlement curve. The stiffness, estimated in terms of the Young's modulus, of the material along the pile shaft is an indication of the amount of ultimate skin friction. The new methodology, in combination with the earlier method proposed by Thilakasiri and Silva [6] to estimate the Young's modulus of the material below the pile bottom, can be effectively used in interpretation of static load settlement curves to determine the type of the material along the pile shaft and that of the material below the pile bottom. The developed methodology is implemented for static load-settlement curves obtained from testing of bored piles and the advantages of the new methodology are demonstrated.