各種基礎 (2)

[VI-594] Development of Load Bearing Layer Detection System to Confirm Arrival at Load Bearing Layer in Building Precast Pile

*清水 智明¹、松倉 勝幸¹、平川 泰行²、後藤 祐一³、岡 信太郎⁴ (1. 奥村組、2. 日本コンクリート工業、3. 佐藤鉄工、4. 地盤試験所)

Keywords:bored prescast pile method, Load Bearing Layer Detection System, Electric Cone Penetration Test

In bored precast pile method, the way to judge arrival at load bearing layer indirectly using the integrated current value of the auger motor is general. But it's sometimes difficult to judge only by increase of the integrated current value. So the " Load Bearing Layer Detection System " to confirm arrival by obtaining N-value through the penetration test performed at an auger bottom.
When a demonstration was performed for performance verification of this system, N-value could be obtained precisely, and I found out that quantitative load bearing layer arrival judgment is possible.