Abstract: The bearing characteristics and load transfer mechanism of rock-socketed pile of large diameter under different vertical loads were researched via vertical compression static load test and pile stress test on three rock-socketed cast-in-place piles with diameter of 800 mm in a project in Indonesia. Test results show that the Q-s curves of the three test piles changed slowly, with settlement smaller than 17 mm, large rebound rate ranging from 54.8% to 70.9%, and small residual settlement as well as large bearing capacity, all meeting design requirements. The axial force of pile shaft gradually increased with the rising of the load on pile top, and gradually decreased along with depth. The change of side frictional resistance of pile was asynchronous: as load increased, the side frictional resistance gradually developed to the maximum in the rock-socketed segment, which, however, was still not fully utilized. The pile end resistance increased linearly with the increase of load on pile top. Under the maximum load, the pile end resistance ratio accounted for about 55%. The research results are helpful to the improvement of domestic pile foundation specifications and the formulation of local pile foundation specifications.

Key words: rock-socketed pile, static load test, forecast of bearing capacity, side frictional resistance of pile, pile end resistance, Indonesia area