PHC桩挤土效应对饱和粉砂层液化消除的研究

Study on soil compaction effect of PHC piles to eliminate slight liquefaction of saturated silty sand layer

针对我国滨海、临河等地区施工场地中常存在的可液化饱和粉砂层,预应力高强混凝土管桩(Prestressed High-intensity Concrete,PHC)设计、施工要求较高的问题,以沧州津水名苑小区项目3号楼为例,研究PHC桩挤土作用对粉砂层液化消除的效果,并通过是否考虑PHC桩对粉砂层液化消除作用的两种桩基方案对比,为总承包项目桩基方案选择提供参考。得出结论:PHC桩不仅能解决地基承载力的问题,同时还能够改变土体的密实状态,消除饱和粉砂层的液化程度。考虑PHC桩挤土效应消除饱和粉砂层液化后,可给工程项目桩基方案提供更多选择,节省投资,并可有效降低施工难度,提高施工效率。

In response to the common problem of liquefiable saturated sandy layers in construction sites in coastal and riverside areas in China,which require high design and construction requirements for Prestressed High-intensity Concrete(PHC)pipe piles,this study takes Building 3 of the Jinshui Mingyuan residential project in Cangzhou as an example to investigate the effect of PHC pile extrusion on the elimination of liquefaction in sandy layers.By comparing two pile foundation schemes with and without considering the effect of PHC piles on liquefaction elimination in sandy layers,this study provides reference for selecting pile foundation schemes for general contracting projects.The conclusion is drawn that PHC piles not only can solve the problem of foundation bearing capacity,but also can change the compactness of soil and eliminate the degree of liquefaction in saturated sandy layers.Considering the effect of PHC pile extrusion on the elimination of liquefaction in saturated sandy layers,more options can be provided for the pile foundation scheme of engineering projects,which can save investment,effectively reduce construction difficulty,and improve construction efficiency.