Stress distributions in rock socketed piles

This paper is concerned with the distribution of loads within rock sockets only, and provides the results of a comparison between elastic solutions and lead distributions obtained by the field testing of four piles with l/d ratios of 2.7 To 11.8. In the elastic range, the distribution of load down the length of rock socketed piles has been shown to be non linear, particularly near the pile top and base. However, it is suggested that the assumption of linearity is reasonable from a practical viewpoint. Further field and theoretical work is required to obtain a more certain appreciation of load distribution near the base of piles. Although differences between the shape of the field and theoretical load distribution are apparent near the base of piles, the two approaches agree in their indication of the proportion of total load which reaches the pile base. The field measurements show that yielding of side resistance increases the proportion of the load reaching the pile base. The field measurements also show that the load distribution after yielding becomes distinctly non linear near the pile base, and implies a sharp decrease in side resistance in that region. The development of theoretical analyses which indicate reasonable increases in radial stresses during side shear are required before a comparison can be made between field and theoretical analyses after yielding has occurred.