With rigid pile composite foundation cushion Mechanism
|School||Huazhong University of Science and Technology|
|Keywords||Rigid pile composite foundation Cushion Negative friction Pile-soil stress ratio Neutral surface depth than|
Composite foundation geotechnical studies of the last two decades the more active areas , while rigid pile composite foundation Composite Foundation is currently the most widely used class . Because of rigid pile composite foundation pile high strength, in order to prevent stress concentration pile , pile -soil interaction assurance , usually in the top of the pile to set a certain thickness of cushion . Cushion technology is a rigid pile composite foundation core technology . In this paper, with cushion rigid pile composite foundation for the study of the mechanism of action and the cushion part of the work of rigid pile traits studied. First, the article describes the typical rigid pile composite foundation - CFG pile composite foundation under vertical load traits , thereby introducing cushion mechanism analysis . After the introduction of several predecessors made ??cushion failure mode and thickness calculation method, the author of the possible failure modes of cushion for the analysis and demonstration , and suggested that the most favorable Cushion Cushion failure modes and calculations reasonable thickness empirical formula is given for projects directly or interpolated lookup table . Secondly, the paper describes the concept of negative friction characteristics and distribution , as well as rigid pile composite foundation pile in the negative friction causes and influencing factors. Quote predecessors used to analyze and flexible piles pile of Meyerhof theory, further analysis of rigid pile composite foundation side effects of increased resistance . The authors also under the pile lateral friction resistance test curves , linear simplified by the top of the pile of negative skin friction maximum and neutral surface depth than control the entire length of pile lateral friction distributed computing , and thus , the establishment of rigid pile composite foundation pile lateral friction linear simplified model . Finally, the authors applied Vesic spherical cavity expansion theory , derived with cushion rigid pile composite foundation pile cushion piercing on the amount of calculation , which in turn launched a new pile-soil stress ratio formula. Then, depending on the pile surface displacement differential equations and algebraic equations neutral , apply semi-analytical method for solving a neutral surface depth than λ, by a numerical example of the compression modulus of pile , pile length and pile soil compression modulus three factors Influencing change on a neutral surface depth than λ influence and rigid pile composite foundation neutral surface depth than λ ranges .