As part of the construction of a multi-span pre-stressed concrete girder bridge for Japan's new high speed rail line, landslide preventive piles were installed on the flank of a steep slope. The rotary press-in piling method was selected to install three parallel rows of long (up to 36m, i.e., 118ft) and large diameter (1,200mm, i.e., 47.2in) pipe piles safely into the slope as a deterrent measure. They were spaced at 2.5 Dia (3.0m, i.e., 9.8ft) on center and were staggered to allow the groundwater to migrate between the piles. Each pile had a sacrificial cutting shoe welded at its toe for speedy installation and was rotated and simultaneously pressed into soil on the slope through the stable bedrock thereunder to achieve a robust landslide prevention in a relatively short period of time.
Takefumi Takuma, Koji Kajino, Masashi Nagano
Keywords: pipe pile, landslide prevention, press-in piling, Gyropress, GRB System
Publisher: DFI