Bridge Pile Buckling And Its Reliability Analysis Method

With the great development of brides with large-scale span in China, the application of superlong and superhigh bridge pile in construction is increasingly popular, so that the bridge-pile buckling analysis (hereafter abbreviated as BPB Analysis) gradually receives its due importance. Being a practically significant topic on project, the BPB Analysis influenced by many factors is rather complicate. Though scholars at home and abroad had made corresponding research during the last century and at the same time they had made great achievements, most of them confine themselves to the research on perfect pile buckling, not considering the influence of many special situations such as the initial bend, the defects in construction and the layered soil, etc...The reliability design has not been advanced according to the design method of probability theory until recent years. For the cooperation of pile-soil, the complicacy of the structure system and the design and calculation system of the pile foundation, and further more for it's difficult to determine the properties of various kinds of soil due to the large scope of samples, there are still some problems in real applications. By the way it seems there is no document or report about the reliability analysis of pile bucking at present. After deeply analyzing the destructive mechanism of BPB Analysis, the author objectively appraises different analytical means of pile buckling at home and abroad, and discusses the influence on pile buckling under special conditions, e.g. the initial inclination and bend of the pile, the layered soil, etc. By doing so, the author puts forward some practical analytical means. Firstly, under different boundary conditions, the author advances a solution to BPB Analysis through the principle of potential energy and the power series solution to BPB Analysis. Secondly, the author puts forward non-linear FEM and has realized the non-linear analysis of BPB by adopting ANSYS. Thirdly, the author has accomplished the non-linear BPB Analysis under the conditions of initial inclination, initial bend and defect, and layeredsoil. Also the author has drawn some valuable conclusions applying to project practice. Fourthly, the author puts forward to analyzing the pile buckling reliability, revising the probability distribution of limited loads of pile buckling by adopting the Bayes' theorem, calculating the pile buckling reliability by applying to the design point method for random fuzzy reliability, stimulating to find the statistically characteristic value of the random variant of limited loads of pile buckling by adopting the method Monts -Carlo, and meanwhile the author raises several calculating methods for the influential factors of pile buckling reliability. Additionally, the author has applied these analytical means to some ready materials of survey models or large-scale spot pile survey and finds that the results are identical with the real survey values.