Research On The Horizontal Restraint Stiffness And Horizontal Bearing Capacity Performance Of The Super-long Bored Pile

Bridge engineering is more likely to employ super-long bored pile, and the cap constraints made by the pile is not fixed. If the calculation of cap constraints is based on the rigid connection, some errors will occur in the calculation results, and even the validity of the results will also be affected. Therefore, the research on the restraint stiffness of the pier exerted by the pile foundation is necessary. With the application of super-long bored pile in engineering practice, increasing attention has been paid to the pile’s horizontal bearing capacity. Moreover, particular focus is given to the pile groups under lateral load. Due to its complex load transfer mechanism and multiple factors, many researches are greatly needed in order to correctly analyze the mechanism of the pile groups’pile-soil interaction, and provide a reasonable, reliable, and practical calculation method for a project. In terms of the horizontal restraint stiffness and bearing performance of the super-long bored pile, this thesis focuses on the following tasks.1. The thesis first recalls the development of the pile foundation, and summarizes the current research and existing problems of the super-long bored pile.2. Then it introduces the calculation method of the horizontal restraint stiffness and bearing performance of pile groups, and elaborates the basic principles of contact finite element and elastoplastic nonlinear theory.3. The thesis sets up a three-dimensional finite element pile-soil contact model with the use of Ansys software, and simulates the process of the loading of pile groups, which together contributes to the formation of load-displacement curve of super-long bored pile groups. In addition, the author discusses the effects of different parameters towards the horizontal restraint stiffness of the pile.4. Finally, the thesis calculates the horizontal restraint stiffness of a single pile, and analyzes the effects of different parameters towards pile groups’effect coefficient by the reflection of the horizontal bearing capacity of pile groups on the basis of cap displacement pile groups effects.