Socket roughness effect on side shear resistance prediction of rock-socketed piles

Resumen

Rock-socketed piles have been extensively employed to receive and transmit large concentratedloads to deeper stronger materials. Although the load transfer mechanism combines base andside resistances, the contribution of side shear resistance is often crucial, as it is usuallymobilized at much lower strains (or pile settlements) than base resistance. The side shearresistance of rock-socketed piles has usually been estimated using recommendations from codesand standards, or using local knowledge obtained from full-scale static load tests performed insimilar ground. There are also empirical formulations as a function of the uniaxial compressivestrength of the intact rock. However, this approach neglects the influence of other importantaspects such as the effect of roughness at the rock-pile interface, and this factor is not alwaysbeing considered in current design practices. The aim of this work is to examine the socketroughness effect on side shear resistance of rock-socketed piles. To do that, DEM2D numericalmodels of direct shear tests, and DEM3D numerical models of rock-socketed piles with differentdegrees of socket roughness are employed. Numerical results suggest that socket roughness isan important factor that significantly increases the load capacity and stiffness of rock-socketedpiles.