Finite Element Analysis On Bearing Capacity Of Pile-end Post Grouting Bored Pile Under Vertical Load

Bored pile has the advantages of simple construction, high bearing capacity ofsingle pile, applicable to wide range of strata, small impact on the surroundingenvironment, so it is widely used in engineering. But there are inherent defects onbored pile,such as collapse of hole wall, mud layer by the side of pile, sediment of pilebottom, coupled with disturbance of the soil of pile bottom in the construction, whichcause pile tip resistance and side friction of pile can hardly fully play, as a result, thesingle pile bearing capacity fail to meet the design requirements. The pile-end postgrouting technology can not only cure sediment of pile bottom, improve the propertiesof pile end soil, also increase the pile-end bearing area and improve the side friction ofpile, improve the bearing capacity of the pile, greatly reduce the settlement of pile top,the bored pile bearing capacity improved greatly.This paper analyzes the main factors on bearing capacity of bored pile by pile-endpost grouting and the mechanism of its increment of bearing capacity. Combined withsoil characteristics in test site, it establishes the model of three-dimensional finiteelement of pile-end post grouting bored pile by using the finite element softwareABAQUS and simulates its bearing characteristics. By changing the pile length, pilediameter, consolidation grouting parameters, the bearing capacity and settlementdeformation characteristics of non grouting pile and pile-end grouting pile are analyzedby finite element simulation and comparison. The analysis results show that bored pilepost grouting technology in a certain pile length, pile end grouting quantity and soliddiameter conditions will significantly improve the bearing capacity of single pile andreduce settlement. The research results can provide some reference for the pile-end postgrouting bored pile design optimization which bearing layer is gravel layer.