STUDY ON MECHANISM AND SETTLEMENT OF THE FRUSTA-LIKE CRUSHED STONE GROUTING PILE WITH BALLASTLESS TRACK SLAB COMPOSITE FOUNDATION

摘要

Frusta-like crushed stone grouting pile (FCGP), a new composite soft-base processing technology developed on the basis of crushed stone grouting pile (CGP), with a transformation of pile heads into pier heads and a transformation of pile bottoms into enlarged ones, which can improve the mechanical properties of pile and soil and reduce composite foundation settlement. The design theory of controlling deformation is more reasonable than that of controlling bearing capacity during the design of the composite foundation. Ballastless track railway must meet the strict requirement of ground postconstruction settlement. In this paper, the technology of frusta-like crushed stone grouting pile is applied into the foundation of high-speed railway of ballastless track, of which the mechanism was analyzed. Also, through ABAQUS package, the characteristics of settlement of the pile and the soil, as well as the transmission pattern of load of composite foundation borne with frusta-like crushed stone grouting pile with ballastless track slab were analyzed. And the degree of the effect of these factors-the diffusing zone replacement ratio and the pile spacing to the composite foundation settlement were also discussed in this paper. All the above results lead to a conclusion, that frusta-like grouting pile can be used into the foundation of high-speed railway of ballastless track and has a significantly effect of reducing composite foundation settlement.