Influence Of Pile Shoe Pulling Out On Fundation Of Bucket Foundation Platform

Both jackup drilling rig and bucket foundation platform belong to shallowfoundation structures. After drilling, the jackup drilling rig with biggish pile shoeswill produce a certain influence on foundation of bucket foundation platform duringpile extracting. Taking Qikou 17-2 bucket foundation platform and jackup drilling rigBohai No.8 as an example, the general-purpose finite element program ANSYS isused to simulate the pile shoe's extracting process of jackup drilling rig by using 3D8-node element and Drucker-Prager elasto-plastic stress-strain theory. At the sametime, three-dimensional finite element analysis is carried out of the influence onfoundation strength of bucket foundation produced by pulling out of pile shoes.The distance between jackup drilling rig and bucket foundation has an extremelyimportant effect on the analysis of influence on foundation strength of bucketfoundation by pulling out of pile shoes. With the exclusion of it, influencing factorsinclude the size dimension of jackup drilling rig pile shoes and the natural parameters,such as, the elastic ration, internal friction angle and cohesive strength of soil. Inaddition, the loads of pile exacting produce different effect on foundation strength ofbucket foundation at different direction. The analysis of influence on foundation strength of bucket foundation by pileextracting is mainly studying the problem of interaction between bucket and soil. Inthis article, the coupling of finite element and contact element in numerical method isapplied to the interaction between bucket and soil;considering the nonlinear materialproperty of soil in the interaction between bucket and soil;programming theDuncan-Chang stress-strain relationship for the using of ANSYS finite elementsoftware;enriching the soil pattern storage of ANSYS software;comparing thecalculative results by using D-P stress-strain relationship with those by using D-Cstess-strain relationship.The research of influence of pile shoe pulling out on foundation of bucketfoundation platform is a meaningful reference for the operating of jackup drilling rig,increasing the foundation strength of bucket foundation and decreasing the influenceof pile shoes exacting of jackup drilling rig.