Study On The Mechanical Characteristics Of Composite Foundation With Large-Diameter Plain Concrete Piles In Cheng Du

Plain concrete pile composite foundation as the rise of a new soil improvement technology, because of the ability to give full play to the potential of pile and soil, has become an important method of foundation treatment.In recent years, China Southwest Architectural Survey and Design Institute proposed the concept of large diameter plain concrete pile composite foundation, and used in Chengdu. compared with ordinary plain concrete pile composite foundation, large-diameter plain concrete piles research is relatively less, there is no reasonable calculation method currently. this dissertation on the basis of previous work, combined with the soil characteristics of Chengdu, through tests, finite element analysis and other means, to study the mechanical properties of the large-diameter plain concrete pile composite foundation to provide a theoretical basis for its design.(1)Based on the result of the tests:get the variation regular of the pile pressure,soil pressure and pile-soil stress ratio, in addition to the boshi masion, the test piles of other three sites are negative friction piles.(2) According to the results of the ABAQUS finite element software, the pile-soil stress ratio and axial force variation with the measured results is basic agreement.(3)By using ABAQUS finite element software to calculate the force characteristics of the different parameters of large diameter plain concrete pile composite foundation.come to the following rule:at the same depth of soil subsidence and vertical stress is evenly distributed, and this distribution pattern does not change with the change of parameters.side friction along the pile basic divided into three linear distribution, and the maximum positive and negative friction position has remained stable.(4) According to the test results and conclusions of finite element calculation,get the design method of large diameter plain concrete pile composite foundation which based on the pile-soil deformation coordination, by comparing the theoretical calculation and the results of finite element,verified the theoretical calculation model is reasonable.