Simulation Experiment Study On The Mechanism Of In-position Drilling Of Jack-up Drilling Platform

Inserting piles is the first engineer operationI in well site of jack-up platform.This thesis summarized correlational researchs on inserting piles and emplacement risk,and analyzed the reason for the differenct inserting depth between the calculating depth and real depth according to different bearing capacity calculating models.It believes that the soil is uncertain,and there will be a big error when evaluating on one singal borehole specimen.There are two design parameters in the soil boundary so there will be a mutation in the calculated ultimate bearing capacity.But practically in the interface of soil there won't appear suddenly increase or suddenly decrease.There are obvious differences between calculation method and actual situation.On the selection of calculation parameters,the selection to mean will cause a larger error.When a single soil layer is thickness,it is suggested to take more design points to improve the accuracy.CPT testing and adjacent well site data of pile is the main factor of reference.In order to study the role of jack-up drilling platform in the pile and soil,on the basis of a large number of experimental data analysis,this paper summed up the following conclusions: soil stress`s relation with ratio of inserted depth of the pile and diameter of pile shoe,variation of the bearing capacity of the pile leg of the jack up drilling platform in sand and clay and variation of the bearing capacity of the pile leg of the jack up drilling platform in egg shell formation.According to the on-site work,it has been tested that inserting pile prediction and risk assessment is an essential part of jack-up drilling platform in place practice.