桥梁工程中PHC桩优化设计

为解决PHC桩在桥梁工程中的推广应用问题,采用FLAC 3D有限元软件、结合实体工程和现场试验对PHC桩桩基和承台的优化没计问题进行研究.通过分析桩长以及桩间距对群桩效应系数和承台荷载分担比的影响,得出桥梁工程中PHC桩的长径比宜为35左右,桩间距宜为3～4倍桩径.通过对承台的综合优化得出不同桩径下合理承台的有效厚度.通过实体工程应用分析得知:PHC桩用于桥梁工程是可行的,提出的PHC桩优化设计方法是合理的,桥梁工程中PHC桩承台符合“撑—系杆”设计模式.

Optimization Design of Prestressed High-Intensity Concrete Pile in Bridge Engineering

In order to resolve the problem of the popularization and application of prestressed high-intensity concrete(PHC) piles in bridge engineering,the finite element software of FLAC3D was adopted to study the optimization design of the foundation and pile cap of the PHC pile,combined with actual engineering projects and field experiments.The analysis of the impact of pile length and the spacing of piles on the group-pile effect coefficient and the proportion of pile cap load shared by piles demonstrate that the length-diameter ratio of the PHC pile in bridge engineering is appropriate to be 35,and the spacing of piles be 3～4 times of pile diameter.Furthermore,by the comprehensive optimization of pile cap,the effective thickness of the rational pile cap under different pile diameter is gained.The application analysis of actual engineering projects proves that PHC piles are suitable for bridge engineering,the optimization design method proposed for PHC piles is reasonable,and the PHC pile cap in bridge engineering conform to the "support-tie" design mode.