Analysis And Study On The Distribution Law Of Side Friction Of Pipe Piles In Handan Area

In order to ensure the safety and stability of the building,the control of its settlement value is very critical.In view of various advantages such as high bearing capacity and small settlement of pile foundation,it has been widely used in engineering construction.There are many methods for calculating the settlement of pile foundations,such as the elastic mechanics method,the stress area method,the layered sum method,and the settlement calculation method considering the historical influence of stress.The layered sum method is a practical calculation method recommended by the specification.When the settlement is calculated according to the layered sum method,the calculation of the additional stress of the foundation soil is very important.The calculation methods are divided into Boussinesq formula,Cerutti formula,and Mindlin formula.In the Mindlin solution calculation formula,the pile end resistance ratio ? and the uniformly distributed side resistance ratio ? on the pile side have a great influence on the additional stress.The object of this study is the applicable values of ? and ? in the stress solution derived by Geddes' integration of Mindlin formula in Handan area.This paper collects the static load test results of 5 groups of engineering piles under various soil conditions in Handan area and the settlement observation data of pile foundation engineering,and analyzes the settlement of single piles in this area.Firstly,the development history of pile foundation is briefly explained,and the research status of pile side friction resistance is analyzed.Then the influence of the changes of key parameters ? and ? on the additional stress of the foundation in the Mindlin stress solution is calculated and analyzed.The formula of settlement calculation formula of layered sum method based on Mindlin-Geddes stress solution was compiled using Matlab software,and the settlement value of single pile was calculated according to the corresponding engineering geological survey data.During the calculation of the additional stress in the settlement calculation,multiple sets of pile-end resistance ratio ? and pile-side resistance ? were sequentially brought in accordance with the rules summarized previously.When the settlement values in accordance with the static load test were obtained,the applicable loads at all levels were obtained.The value of the load distribution coefficient ?,?.Then the corresponding engineering model was established using Abaqus finite element software,and the values of ? and ? were extracted and calculated through the calculation results.Finally,the values of ? and ? suitable for the pipe pile foundation in Handan area were given.