Installation and vertical loading tests of screwed steel pipe pile, which has helical wing on the pile edge, were executed in uniformly graded sand in a calibration chamber. The experimental factors are the relative density D_r(72, 94%), the pile diameter do (48.6, 76.3, 101.6mm) and the surcharge pressure σ_0 (50, 100, 150kPa). It was proved that the residual stresses of screwed pile installed in the dense sand amounted to high ratio, and the load deflection curves of the pile top due to vertical load were different from those of the other piles such as jacked pile or bored pile. We have discussed the effect of the residual stresses upon the bearing capacity of the screwed pile.%回転貫入杭は，鋼管の先端面または杭周面に溶接された螺旋翼や 平板（以下，本論文ではこれらをまとめて羽根と呼ぶ）が回転推進 力となって，土を側方に押しのけて設置される，設置後にはこれら の羽根が杭の鉛直支持力を増加させる要素として機能することを基 本的な特徴としている．その点で，回転貫入杭は従来の分類（打込 み杭，埋込み杭，場所打ち杭）とは異なる第四の杭工法と云える．
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