Research On Horizontal Load-bearing Capacity Of Large Diameter Steel Pipe Piles

With the development of large-scale,deep-water port and the construction of offshore wind power engineering,the application of steel pipe pile foundation presents a large diameter development trend.As a wind power foundation,the diameter of single steel pipe pile is generally 3m to 5m.Large diameter steel pipe pile has large bearing capacity and strong bending ability,and can bear large horizontal load.However,sharply increase of pile diameter and pile length makes it difficult to evaluate itself accurately using the traditional design method of small diameter pile.The horizontal bearing characteristics of large diameter steel pipe piles are analyzed in this paper.Firstly,the existing horizontal bearing capacity calculation method of pile foundation domestic and abroad is summarized.Secondly,the model of single large diameter steel pipe pile is established by using ABAQUS finite element software.By comparing the load-displacement curve and pile deformation curve of field static load test and finite element method result,the reliability of finite element model is proved.And then,influence of steel pipe scale including pile diameter,pile thickness,buried depth,cantilever length,and soil parameters including friction angle,cohesive force factors these two aspects on bearing behavior of large diameter steel pipe pile is studied.The influence rule is analyzed and the main influencing factors is summarized.After that,based on the study of bearing characteristics of single large diameter steel pipe piles,large diameter steel pipe pile is applied to the wharf structure.With the background of 100 thousand ton container terminal project in Tianjin port area,a new type of wharf structure is designed,it mainly consists of large diameter steel pipe pile,anchor structure,steel rod,and bored piles are the foundation of container crane track beam Aiming at the most unfavorable condition of the combination of mooring force,cargo load and container crane load,the overall stability of wharf and the stability of anchorage structure is analyzed by means of strength reduction method and other methods.The strength of steel pipe pile and steel rod is calculated by extracting the distribution of bending moment and shear force.In addition,the bearing capacity of bored pile foundation is analyzed.Finally,the pile diameter,pile thickness and steel rod spacing of new wharf structure using large diameter steel pipe pile are optimized.In summary,based on the research of single large diameter steel pipe pile,a new form of wharf structure is proposed,the corresponding analysis method is summarized,the results have great significance for promoting large diameter steel pipe pile in application of large and deep water wharf and offshore wind power foundation.