Study On The Bearing And Deformation Behavior Of Ship Lock Passive Piles On Soft Soil Under The Side Fill Load

The ship lock built on soft soil generally uses the pile foundation,while the ship lock engineering usually needs the backfill on both sides of the lock wall.The side fill load will lead to lateral soil movements,which will produce horizontal earth pressure on the pile foundation under the ship lock,and make the pile flexural or even break,and threaten the safety of the upper ship lock structure.The influence of the side fill load on the pile foundation of ship lock on soft soil is a typical "passive pile" problem.At present,the research on the passive pile problem of ship lock on soft soil is mostly from the perspective of construction and monitoring,while the theoretical research is less.Based on the collection and analysis of previous studies,this paper uses the finite element software ABAQUS to carry out three-dimensional numerical simulation,and studies in depth the bearing and deformation behavior of the ship lock passive piles on soft soil under the side fill load.The main research contents and results are as follows:(1)Based on the literature reading and analysis,the engineering characteristics of the ship lock passive piles on soft soil under the side fill load are discussed from the perspective of the mechanical mechanism.(2)Based on the finite element software ABAQUS,the model of passive pile groups on soft soil is constructed,the bearing and deformation behavior of passive pile groups of the lock wall under side fill load is analyzed,and the effect of vertical load of the lock wall on the stress and deformation of passive pile groups is studied.The calculation and analysis results show that: the bending moment and lateral displacement of the back row piles are less than that of the front row piles due to the "blocking" effect of the front row piles;restraint effect of side fill on the bottom board of ship lock reduces the lateral displacement of the front and back row piles,and increases the bending moment of the pile top;the vertical load of the lock wall has no obvious effect on the bending moment and lateral displacement of the passive pile groups.(3)Based on the model of pile-soil-structure interaction,the bearing and deformation behavior of the ship lock passive piles on soft soil under the side fill load is analyzed,the calculation results of the pile-soil-structure interaction model and the pile group model are compared,and the influencing factors of the stress and deformation of the the ship lock passive piles on soft soil are discussed.The results of calculation and analysis show that: in the multi row passive piles under the bottom board of ship lock,the bending moment and lateral displacement of pile body decrease rapidly with the increase of row number,and the side filling load has little influence on the settlement of pile top;after considering the pile-soil-structure interaction,the calculated bending moment and lateral displacement of pile body decrease to a certain extent;the height and width of side filling,mechanical parameters of soft soil,thickness of soft soil layer affect the bending moment and lateral displacement of the ship lock passive piles greatly,and the pile diameter affect the bending moment more significantly.(4)Taking the second line ship lock project of Qingyuan junction in Guangdong Province as the engineering background,the finite element modeling analysis is carried out for the stress and deformation of the pile foundation of the lock chamber section after backfilling.Combined with the monitoring data of the main body structure during the backfilling construction period,the rationality of the theoretical analysis in this paper is preliminarily verified.