Indoor Model Test And Finite Element Strength Subtraction In The Application Of Single Pile Ultimate Bearing Capacity

In recent years, with the acceleration of Chinese modernization, the number of high-rise,super high-rise buildings and across-river, across-sea bridges has so rapidly increased that theupper limit of the pile foundation structure for a higher bearing capacity requirements. Butnow the basis for the calculation of ultimate bearing capacity of the pile, the study is not veryclear, so far no realistic method of calculation. Numerous studies show that: the pile sideresistance and tip resistance is common to play a role, but previous studies have focused onthe pile side resistance and tip resistance were to be considered, there is a contradictionbetween theory and practice. Therefore, we use the strength reduction will pile tip resistanceand side resistance combined for analysis to explore and strive to calculate the ultimatebearing capacity of pile foundation is more accurate,Firstly, the paper introduces the pile foundation’s role, development process, thedevelopment status of the theory of the pile, the pile bearing capacity factors difficult to studyultimate bearing capacity and faces; and many scholars at home and abroad on the basis of thetheoretical study of pile on the basis of the study of ultimate bearing capacity of the pile aresummarized.Then, pile load transfer theory made simple induction; various analytical methods pilebearing traits, respectively, from the assumption that the applicable conditions, researchresults and the advantages and disadvantages of each method are discussed in detail，For theconcept of skin friction and tip resistance, the impact factor calculation method aspects thatare discussed for the study of ultimate bearing capacity of the follow-up will be carried out toprovide a theoretical basis.Third, respectively, from the significance of the model test, similar to the principle,design, equipment and instruments, measuring the physical properties of soil samples,loading systems, data acquisition systems, has made a detailed presentation。And the pileunder vertical loads failure modes and mechanisms of detailed analysis and finally, the lack ofindoor model test part of the preparatory work and the need for future improvements.Fourth, the third chapter analysis the data for indoor experiences so that carried outchanges in the load-settlement relationship, in the relationship between the axial force alongthe pile, in the relationship between skin friction along the pile, the pile tip resistance pilelateral friction curve load sharing, load sharing percentage curve, and a detailed analysis ofthe factors affecting the changes in various curves.Fifth, starting from the pile foundation bearing mechanism, this chapter using the finiteelement MIDAS/GTS Strength Reduction Analysis Software and theoretical research work Carried out pile foundation limit state, which presents unlike traditional security limitload factor of pile foundation safety reserve factor concept, drawn pile foundation strengthreduction limit analysis determines conditions. Through the actual pile limit analysis, showedthat the finite element strength reduction can effectively evaluate the safety limit state pilefoundation reserves and ultimate load. Ultimate load on pile foundation determination hassome practical significance.