Situ Tests of Bearing Character on Large Diameter Deep Socketed Pile in Qingdao Gulf Bridge

Abstract

With the development of long-span bridge engineering and increase of load on construction, the piles which socketed in rock more than 5 diameters have been used in some bridge engineering. Based on the technique of Anchored piles method, the static load tests of large diameter and deep socketed piles had been carried out in Qingdao Gulf Bridge. The bearing characteristics of large diameter pile were analyzed, including the load displacement curves of test pile; the axial force; the relationship between side friction and displacement and the sharing ratio of side resistance and end resistance. Finally, the test results were compared with specifications, The results showed that the bearing characteristic of deep socketed piles was as same as the friction piles in this area; from the results of test the side friction of pile could be estimated lower in strongly weathering breccia area while the friction in strong- weakly weathered breccia was relatively close to the value of exploration reports. At the bottom of the pile, because the relatively displacement of pile-rock was small, the pile side resistance is relatively small. It could be seen that the estimate of bearing capacity was less than the test result, and the pile foundation was safety enough.