The Research On The Affect Of Collapse State And Bearing Capacity Of The Soil Layer Adjacent To The Plate Of Pile Of The Multi-Extruded-Expanded-Plates Pile

The Multi-Extruded-Expanded-Plates pile as a representative of new variable cross-section pile is the pile type which is based on the bored pile,using a dedicated squeeze expanding equipment in the pile body, squeezing and expanding into plate,and then pouring concrete to form pile body, bearing plate and pile root to common loading. The Multi-Extruded-Expanded-Plates pile can greatly improve the compressive and uplift bearing capacity, especially has obvious effect on improving the uplift bearing capacity, has the advantages of high bearing capacity of pile foundation, design flexible, small and uniform settlement, cost saving, etc. It is worthy of further study and promote.In recent years, the theory of the Multi-Extruded-Expanded-Plates pile has a certain development, but still lagged behind the engineering practice, at present, the theory research on the Multi-Extruded-Expanded-Plates pile is mostly in the single soil layer, the whole pile in cohesive soil with high bearing capacity. Although the soil properties is stable and advantageous for the simulation analysis, but differ with the actual project. In practical engineering, the geological conditions is complicated and foundation soil are mostly different properties soil layers, the thickness of soil layers are also different. The physical properties of the soil at the junction are complicated and the stress state of the bearing plate of the Multi-Extruded-Expanded-Plates pile is complicated, the pile has been successfully applied in many kinds of soil in the actual engineering. Therefore, in order to match the actual project as far as possible, when established the model, this paper put pileinto the soil which composed of three kinds of soil for innovative, from top to bottom respectively are silt(or sandy soil, mucky soil), silty clay, caly(or gravel soil, shale).Researching the impact of different physical properties of soil layer adjacent to the soil which with the bearing plate on the bearing capacity of pile and damage state of soil surrounding the pile. This paper is based on the study of the finite element method, simulating analysis by ANSYS software, by changing the different physical properties(mainly refers to the moisture content and soil thickness) of soil layer adjacent to the soil which with the bearing plate to determine the impact of the bearing capacity of single pile, effect of pile and soil and the soil damage state under the vertical load. Using the strength theory, theory of sliding line to systematic study and correcting the calculation formula of bearing capacity of single pile of the Multi-Extruded-Expanded-Plates pile, eventually improve the basic theory of compression and uplift of single pile of the Multi-Extruded-Expanded-Plates pile.