Study On Applicability Of P-y Curve Of Large Diameter Single Pile In Offshore Wind Power Foundation

With the rapid development of wind power industry of the sea in recent years,the application of the pile foundation has the characteristics of pile diameter and pile depth are increasing gradually,the design of pile foundation considering the influence of pile under horizontal load.Single pile foundation has many advantages,such as convenient construction,simple structure and so on.Single pile foundation,the advantages of large diameter single pile is more prominent,but the level of bearing capacity determination method based on the research results of small diameter pile,and relevant industry standards for the design of the large diameter single pile did not give specific methods,so it has an important significance to study on bearing behavior of large diameter single level pile.The p-y curve method can better reflect the nonlinear characteristics of pile and soil in the research and analysis of laterally loaded piles.The p-y curve method is not only suitable for the small displacement of pile,but also has more advantages than other methods in the large displacement of pile.Because the p-y curve method is based on the experimental data of small diameter pile,the applicability of this method for large diameter pile is needed to be verified.The experiment of large diameter piles requires a lot of manpower and financial resources,and it is difficult to carry out the prototype test.Therefore,the main contents of this thesis are as follows:(1)Applicability under static load in different pile diameter p-y curve was simulated by the finite element software ABAQUS,when the pile diameter is less than or equal to 3 m,p-y analysis of API code with finite element software results;when the pile diameter is 4~6 m,obtained by the API specification to the displacement more than the finite element software simulation results.(2)A three-dimensional solid model is established for a wind power project in Bohai Bay according to soil parameters.The results show that under the same load,the displacement calculated by the API formula is greater than that of the software simulation.(3)The influence of pile-soil parameters on the displacement and bending moment of large diameter piles is analyzed.The influence of pile diameter,pile length and modulus of elasticity of soil on the displacement and bending moment of pile is relatively large.