The Research On The Affect Of Collapse State And Bearing Capacity Of The Multi-Extruded-Expanded-Plates Pile Under Different Soil Layer Properties

The Multi-Extruded-Expanded-Plates pile is a new type of pile foundation that through special squeeze expanding equipment to change diameter of the pile in the particular location which named the bearing plate to improve the capacity of the pile.The bearing plate has the function of similar to the end bearing and increase the side-friction of pile with different slope angle. It improve the compression and uplift bearing capacity, especially for the uplift bearing capacity. So the MEEP pile has the advantages of high bearing capacity of single pile, small settlement,saving cost and so on. It deserved to research and promotion use.In order to guide the practice better, the paper researched theoretical further for the present theoretical research of the MEEP pile has shortcoming and far behind the engineering practice. The present theoretical research almost put the bearing plate in the cohesive soil entirely which has higher bearing capacity, which ignored the other properties of soil’s influence on bearing capacity such as back fill soil, sandy soil and rock soil. Actual project has been successfully used the pile in a wide range of soil.The present study put the bearing plate in the same soil layer completely which ignored the effect adjacent layers in the practical engineering. So the models established in the paper are similar to the practical engineering which layers from the top to the bottom are back fill soil, cohesive soil or fine powder sand and hard paste.The thickness of soil layer up and down the bearing plate and moisture content all have the effect on the bearing capacity and the failure state of soil surrounding the pile when research the soil which the bearing plate in. In order to make up for the defects in the current study of the MEEP pile to further improvement the basis of theoretical research, the paper by changing the different characters of soil which the bearing plate in(Mainly refers to the moisture content and soil thickness) to make sure the effect of bearing capacity of single pile, the effects of soil, the punching failure, the sliding failure of the pile under the action of vertical load. The researchalso based on the study of the finite element method, the ANSYS software analysis,strength theory and the sliding line theory. Eventually improve the basic theory of ultimate compression and uplift bearing capacity of single pile of the MEEP pile and amend the calculation mode of bearing capacity of single pile.