Analysis Of Axial Load Capacity And Test Research On Large-diameter Bridge Pile

As the commonly used foundations in the bridge engineering, large-diameter bored piles have many advantages, such as high bearing capacity, good stability, little and homogeneous vertical settlement, facility for mechanician construction and good applicability. Some aspects of the current design and calculation methods are still imperfect and to be developed. According to the settlement of the pile top, the vertical bearing capacity theory is analyzed herein.In this paper, the load behaviour and failure machanism of pile under axial load is analyzed, and the conventional calculation methods with their limitations are summarized. Based on the current theory, a set of load transfer model is proposed and the formulas of calculating the load capacity of the pile embedded in homogeneous or layered soil with their program are derived herein. The good agreement between the results and in-site test data indicates that the proposed calculation theory is accurate and reliable which can calculate the axial load applied at pile top according to the settlement of the pile top and reflect the load transfer behaviour.Sponsered by Hunan Provincial Communications Department, a great in-site static pile test is carried out for the Maocaojie bridge, which is introduceded in details in this paper. From the test, some results with value of theory and practice are obtained about the axial laod capacity of large-diameter bored bridge piles in the area of Dongtinghu lake.