Abstract:To improve the uplift bearing capacity of pile foundation in southeast coastal area, a new type of uplift rock-socketed pile with a bidirectional rotary-expanding bell set in the upper rock layer of the rock-socketed segment is developed. Based on a project in Foshan city of Guangdong province, the static uplift load tests of single pile were carried out. It was observed from the tests that the kind of piles are more excellent in the uplift bearing capacity than conventional piles or belled piles. A hyperbolic model describing the ultimate bearing capacity of the type of piles is established by referring to in-situ data. On the basis of Hoek-Brown failure criterion and uplift bearing mechanism, the uplift failure mode is proposed for this rock-socked pile, and the corresponding calculation method for ultimate uplift bearing capacity is established. In the proposed calculation method, the influences of rock mass properties of rock-socketed segment under the bearing bell, rock mass properties of the rock stratum in which the bearing bell is located, the angle of bearing bell and the thickness of overlying rock layer on the ultimate uplift bearing capacity of this rock-socked pile can be reflected effectively. Compared with the results from the specification calculation method, the results from the proposed calculation method are in better agreement with the field test results, indicating its good application prospect.
张德华 郭腾 崔隽. 岩层设承力盘的嵌岩桩抗拔静载试验及计算方法研究[J]. 土木工程学报, 2021, 54(8): 120-128.
Zhang Dehua Guo Teng Cui Jun. Study on static uplifting load test and bearing capacity calculation method of rock socketed pile with bell bearing in rock stratum. 土木工程学报, 2021, 54(8): 120-128.