Performance Analysis Of Pile-plate Wall System With Rectangular Pile And Circular Pile At Ji-Tu-Hun High Speed Railway Cutting Slope

Pile-plate retaining wall is a commonly used form of support for high-speed railway cutting slope support in complex slope sites.At present,pile holes construction of pile-plate retaining wall in the project can only be based on manual digging,which leads to long construction period,poor construction conditions and great safety hazards.Solving or circumvent the defects of current construction methods,and developing safe,efficient and reliable engineering construction techniques and building methods will promote the industrialized development of traditional engineering construction in China with great sense.There are many applications for circular anti-slide piles in deep foundation pit support and highway slopes,and the circular pile hole can be mechanically drilled or pounched,which can avoid efficiently the defects in the construction of rectangular pile-slab walls well.Therefore,it’s a feasible idea to optimize the pile-plate wall by replacing the rectangular anti-slide piles with circular piles.In this paper,the three-dimensional finite element model of the pile-slab wall of artificial cutting slope is established based on the section at Yanji of Ji-Tu-Hun high-speed railway project.The simulation is carried out and verified to analysis the behaviors of the pile-slab wall after roadbed excavation.Parameter Sensitivity analysis for some critical parameters,such as pile length,pile spacing,pile section size and pile stiffness,is carried out to analysis the characteristics of the pile horizontal displacement,earth pressure and internal force of the pile.On the basis of the established three-dimensional finite element model,a new finite model for manual excavation slope supported by new pile-plate wall is estabilished by replacing the rectangular anti-slide pile with circular pile.Similar parameter Sensitivity analysis for the critical parameters,such as pile length,pile spacing,pile section size and pile stiffness,is conducted to analysis the characteristics of the pile horizontal displacement,earth pressure and internal force of the pile.The difference of behaviors between new pile-slab wall and pile-slab wall of general form is compared.The results show that the trend of the behaviors,such as the pile horizontal displacement,earth pressure and internal force,are consistent for the two types of pile-plate wall.Finally,based on the strength reduction method of finite element analysis,the slope stability analysis of the typical section of the Yanji section of Jituo high-speed railway is carried out.The safety factor of the slope after excavation is used as the critical factor to evaluate the supporting performance of the pile wall.The feasibility of applying the new pile-slab wall to practical engineering is discussed combined with material usage of the retaining structure.The results show that,by increasing the length of the pile,the new pile-plate wall can obtain effective supporting performance corresponding to the general form constructed with basically the same materials.Therefore,it is feasible to apply the new pile-plate wall instead of the general form in some cases.