Abstract:In order to study bearing characteristics of deep rock-socketed piles (hr/b≥5), based on the test results of self-balancing test of zh12 pile in Qingdao Gulf Bridge, the bearing characteristics of deep rock-socketed piles were analyzed. The relation between sides shear resistance of the piles and its displacement socked in soft rock was researched, and the relation between end bearing resistance and displacement was studied. The hyperbolic distributions on the load transfer method were compared to them. The results indicate that Q -S curve of large diameter deep socketed pile in soft rock area declines slowly, approximately in linear distribution. According to the fitting curve based on measured results, it is feasible to fit the relationship between sides shear resistance and its displacement by using hyperbola. The parameter of 1/b also reflects the ultimate side resistance values of piles. The load-displacement curve at the top of pile is similar to the hyperbolic form. By using the parameters of a、b obtained from fitting curve, the calculated load-displacement curve on top of pile is close to the measured curve of self-balance method. At last, according to the measured results, the value range of parameterαin empirical formula was analyzed under different states of axial compressive strength.