Experimental Analysis On Interfacial Shear Strength In Penetration Of Super-Long Piles In Ocean Engineering

In ocean engineering, the large-diameter and super-long pile can be seen as a frictional pile because of its long length, indicating that the lateral friction plays a significant role in the bearing capacity of the pile. According to in situ measured data, the lateral friction of the pile tends to be lower than the friction obtained by calculating the parameters of soils in the penetration process of super-long piles. This is caused by large deformation shearing during pile driving and might lead to a reduction of the pile-bearing capacity, which may render engineering projects unstable and unsafe. To study the lateral friction of piles in ocean engineering, large-scale direct shear tests and ring-shear tests were performed to investigate the interfacial shearing behavior of pile-soil during the pile-driving procedure. Three kinds of soil samples, including sand, silty clay and clay, were used in the tests to study the interfacial shearing behavior of soils of various textures. A reduction coefficient was proposed to determine the interfacial strength by referring to the soil strength. Based on the test results and previous works by other researchers, a discussion of the analysis of the factors that influence the residual strength of the soil is provided.. Advice for engineering projects is put forward in accordance with the analytic conclusions in this paper.