The Application Of Cast-in-place-pile Post Grouting Technology In Bridge Engineering

Today, cast-in place pile is the main form basis in the high-rise building and bridge foundation. Traditional pile hole technology can produce bottom sediment and mud pile skin, resulting pile tip resistance and friction significantly lower. However, post-grouting technologies of bored piles can reduce the adverse impact from bottom sediment and mud pile skin, improve the interaction between pile and soil, increase bearing capacity of pile greatly, as a result, the technology shows a strong trend and expanding scope of its application.This paper focuses on the bearing capacity of post grouting bridge pile, which located in the soil of lower Yellow River region. The function mechanism and effect factors of post-grouting technologies of bored piles increasing bearing capacity of pile are studied by studying the function mechanism between grout and soil around the pile, and the construction technology of post-grouting technologies suit for lower Yellow River region is summarized, making the post-grouting technologies used better in engineering practice.Based on the analysis above, these problems had been refereed below:First, in this paper, based on a wide review of relevant research home and abroad, the working mechanism of post-grouting technology and main factors affecting the pile bearing capacity are studied.Second, by contrasting computational methods of post-grouting technologies to determine grouting pressure and volume, parameters and computational methods of post-grouting technologies are summarized to determine grouting pressure and volume suit for Soft soil characteristics in Bin Zhou area.Third, ultimate bearing capacities of the pile before and after grouting are contrasted and analyzed by finite element analysis and static test, to determine the value post-grouting technologies contributing to bearing capacity of pile. and the design and calculation formulas of post-grouting technologies suit for Bin Zhou area are determined. Fourth, effective construction technology is proposed based on the actual test, and the process flows, serous type, grouting pipe arrangements and grouting accident prevention of post-grouting technologies are illustrated.Fifth, Because of the different designing philosophy between bridge pile and building pile due to load, layout and environment, the contribution ratio of bearing capacity of post grouting was analyzed in bridge pile engineeringSixth, compared with the traditional construction process, economic and social benefits and application of grouting pile are analysised, and the shortage of grouting pile and the next direction needing key research are introduced.