Mechanical Behavior Analysis Of Conductor Anchor Node

The exploration and development of marine oil and gas resources continue to march into deep water,and technical problems in engineering have followed.The poor bearing capacity of the submarine soft soil foundation,combined with the heavier blowout preventer group and the deepwater functional tank integrated with various production equipment,make the stability of the underwater wellhead structure more challenging.In a new generation of underwater production systems,an innovative design that combines a suction foundation with a wellhead structure is used.As an effective solution to the bearing problem of large structures on the soft soil layer under the sea,the conductor anchor node has the advantages of short construction period and strong structural adaptability.Unlike the long conduit pile foundation structure of the conventional wellhead,the working mechanism of the conductor anchor node is closer to the large diameter cylindrical structure.Under the combination of specific working conditions and specific loads,the failure modes,ultimate bearing capacity of the conductor anchor node and the complex interaction with the nonlinearity of the soil are urgently needed.Focusing on the above issues,the main work of this paper is as follows:(1)The theoretical analysis and finite element calculation of the ultimate bearing capacity of the conductor anchor node are carried out.The results of the two methods are compared.The applicability of the theoretical analysis calculation is verified,and the failure mode of the conductor anchor node under specific load is clarified.(2)The finite element analysis software ABAQUS and USDFLD subroutine were used for secondary development,and the soil circulation weakening model was implemented in ABAQUS for quasi-static calculation of suction-loaded wellhead device under cyclic loading.(3)The finite element model of the conductor anchor node and the foundation soil is established.The quasi-static method is used to calculate and analyze the cyclic bearing capacity of the suction-loaded wellhead device under various load combinations,and the ultimate bearing capacity under static load is compared.The effect of cyclic loading on the bearing capacity of foundation soil and structure.