Model Test On Vertical Bearing Capacity Of Rigid-flexiblecomposite Bag With Enlarged Bottom

The rigid-flexible compound bag-enlarged-bottom pile is constructed by the hole-injection method.The static pressure is mainly noise-free,and the weak soil has little influence on the surrounding environment.No mud wall protection is required,no mud pollution occurs,and the bag is injected into the end of the pile.Slurry is limited within the effective range to achieve controlled and effective grouting and the expansion of the pile end.The grouting solution is limited to the effective range,no pollution to the soil at the pile end,composite green construction and environmental protection concept.At present,the actual engineering field at home and abroad uses different types of rigid-flexible compound bag-enlarging piles for reinforcement and combines the experimental techniques with practical engineering cases to summarize the construction technology and the pile-forming mechanism,but for the rigid bulging piles.The most reasonable and reasonable bottoming-end size is economically reasonable,and the rational soil cement thickness of a rigid-flexible compound bag-enlarged-bottomed pile derived from a reasonable rigid bulging pile is not well understood.The deficiencies in the study of the bag-enlarging bilging piles,the main work and results of this paper are as follows:1.The history of the development of rigid-flexible composite pouches with enlarged bottomed piles was reviewed.The research on the vertical bearing mechanism of rigid-flexible composite pouches with enlarged bottomed piles was introduced.The construction technology of rigid-flexible compound pouches with enlarged bottomed piles was introduced.The research status of domestic and foreign research methods for detection methods was reviewed.The theoretical and theoretical studies on the bearing mechanism and bearing capacity of the rigid-flexible compound bag-enlarging pile were reviewed.2.Introduce the technology of rigid-flexible compound bag-enlarged-bottom pile through practical engineering application.Introduce the process flow,operating points,and quality and safety assurance control measures of the rigid-flexible compound bag-enlarging pile.3.Introduced the model test program,introduced the design of the model box,loading device and loading scheme,pile arrangement and measurement system.4.Through vertical compression test of pipe piles,rigid enlarged bottom piles,and rigid-flexible composite bags,the QS curves of the model piles,the ultimate bearing capacity of the single pile,and the axial force of the pile were sorted out.With side friction resistance distribution,pile end resistance,load sharing ratio.Based on the model test,the acceptance mechanism of various pile types was studied.5.Using ABAQUS finite element software,the vertical load-bearing traits of rigid periphlegm piles,rigid-flexible bladder bags and composite pedestal piles were analyzed.Combined with the test results,the optimum diameter of the bottom-end and the best cement were further analyzed.Soil thickness.