Experimental Study On Undisturbed Soil Of Plate Spacing And Plate Number Affect Uplift Failure Mechanism Of The Plates-Expanded Pile

On the basis of ordinary pile,the concrete plates-expanded pile by extrusion or spin expansion device increases bearing plate on the pile to achieve the traditional pile improvements,this improvement is to add a new bearing plate to bear the load on the basis of bearing the friction force or the end bearing force of the ordinary pile.Therefore,as a new type of pile foundation,concrete plates-expanded pile has better mechanical properties compared with the traditional pile foundation.Its compression,uplift and anti overturning ability are better than ordinary pile,and can effectively reduce the pile length,save the project cost,with high practical value.Current research on the concrete single-under-reamed pile has achieved some results,but there is about certain lack of research on concrete multi-under-reamed pile,the influence of a part of the bearing plate parameters on the bearing capacity of the plate-expanded pile is not clear,and it is serious impact on the popularization and application of the plate-expanded pile in the engineering.In order to better guide the engineering practice,this paper will explore the impact of plate spacing and plate number on the uplift failure mechanism of the concrete plates-expanded pile.Based on the study of the concrete single-plate pile,adopting relatively fixed and reasonable plate diameter and slope toe and only change the plate spacing or plate number,In order to further clarify the influence of these two plate parameters on the uplift resistance of the concrete plate-expanded pile.Small scale model test is widely used in the present study,and the soil is processed by hand in the laboratory,but this kind of test,the influence of the difference of the soil mass on the bearing capacity of the expanding pile is neglected,the moisture content of different soil,internal friction Angle,cohesive force and the form of different structure,will make the result of the test is not the same.Therefore,this study tested using undisturbed soil that uses a special device to collection in the construction site,so the most original physical shape and mechanical properties of the soil are maintained.The results of this test and the results of engineering applications are much closer,combined with ANSYS simulation analysis,comparison and validation of the results of the undisturbed soil model test in order to guide the engineering practice more directly.Through the research of this topic,we will be more clear about the impact of plate spacing and plate number on the uplift failure mechanism of concrete plate-expanded piles,and further improve the theoretical research of concrete plate-expanded pile,these will provide a richer theoretical knowledge for the practical application of the concrete plates-expanded pile.In this project,the undisturbed soil was used to carry out the experiment,which can provide reference experience for future similar test.This research will make the practical application of the concrete plate-expanded piles more bright application in engineering.