Abstract：
Current subsurface excavation subway stations in Beijing were constructed using new Pile-Beam-Arch (PBA) method. This method only reserves the upper pilot tunnel, in which crawler-type hole pile driller to drill hole, but drilling hole in sand gravel stratum may cause hole collapse easily. During construction of Fufengqiao Station of Beijing subway line 16, various measures, such as increasing pilot hole depth, strengthening grouting at hole top and ensuring slurry quality, etc., were adopted to successfully reduce or eliminate hole collapse phenomenon.
