Research On Stability Analysis Theory And Optimization Design Of Piled Wharf Bank

Piled wharf is the most common form in the offshore soft soil foundation,the overall stability of bank is the key of wharf security,also decides the width of pile caps and engineering cost.This paper use the FEM Program PLAXIS to research on the stability analysis theory and the optimization design,new shore-connecting structures of piled wharf bank.Firstly,analyze the difference and relevance between the strength reduction finite element method and the Swedish slices method.The statistics of 108 groups of different conditions of the slope stability calculation results show that,if the safety factor of the finite element calculation used in engineering practice that should be to 10% reduction,even if the definition of safety factor in these two methods has the same form.Secondly,it points out the five slip arc modes of bank,and the soil strength conditions when different slip arc modes occurred were studied with the strength reduction FEM.Meanwhile,from calculation we reach a conclusion that when the safety factor comes close to the safety threshold defined by the engineering standard, there will be a drastic change in the lateral displacement.Thirdly,when the shore-connecting structure is ripped-rock slope type,optimize the original design and that with different slope reinforcement method under four different slope height,it indicates that reinforcement effect of underwater vacuum preloading method is remarkable and it can save project cost of 270000 yuan or so for each meter than original design.Finally,research on new shore-connecting structures,as point out that using the CDM or large cylinder as shore-connecting structure can save cost around 240000 yuan.In conclusion,this paper mainly does analysis on stability analysis theory and summarizes the technical and economic benefits of different foundation reinforcement method and new shore-connecting structures.The research findings have great significance on the slope optimmization and the selection of calculation method.