Study On Mechanical Behavior Of Inclined Pile Link-banked Structure Of Deep-water High-piled Wharf

Shanghai Yangshan Deepwater Port is the first port in our country,which is far away from the mainland and built on the small island chain.Its wharf type is the high pile beam slab wharf,and the back bank structure used for retaining soil adopted the inclined roof pile structure.The structure is rigidly connected by a pile cap,an inclined pile,a sheet pile and a support pile,forming a whole.In actual construction,the mechanical characteristics of the pile are very complicated due to the influence of high backfill and weak foundation.At present,there are some shortcomings in understanding the stress characteristics of the inclined roof pile.In order to accumulate experience and provide reference for deep-water construction in China,on the basis of analyzing a large amount of research data,this paper studied the stress characteristics of the skew pile with the shore structure of phase I project of Yangshan port.Firstly,the geotechnical centrifuge model test is used to simulate the structure of the inclined roof pile.The stress characteristics of the structure with the soft soil consolidation during the construction period are analyzed.Based on the study of the physical model,the plane strain mathematical model of the shore structure is established by using the finite element simulation technology,and the mechanical characteristics of the structure during the service life of the wharf are studied.The main research results and conclusions are as follows:(1)The geotechnical centrifugal model of the prototype structure is established,and its simulation satisfies the similarity and error requirements.In the experiment,the displacement of pile cap,the axial force and bending moment of pile are measured,and the test results are verified by the prototype observation data.The results show that with the consolidation of soft soil,the deformation and stress of the shore structure have the "time effect".(2)The model study shows that the consolidation of soft soil has more significant influence on the axial force and bending moment of sheet pile and support pile.In practical construction,it is suggested that many measures should be taken to weaken the influence of foundation consolidation on the structure.(3)On the basis of studying the physical model,the experimental results are verified by finite element simulation,and the mechanical characteristics of the structure during the service life of the wharf are further studied.The load of the rear yard and the load on the top of the pier are mainly considered in the service life of the wharf.Through the analysis of the deformation and stress of the shore structure under different loads,it is pointed out that the force of the structure has the "overall effect" characteristics.Based on the study of the mechanical behavior of the composite oblique pile top shore structure,the functions and stress characteristics of each pile in different stages are further clarified,and some suggestions for the construction and design of the pile are put forward.The main conclusions of this paper have certain reference value for engineering application.