鋼管形式による杭頭半剛接接合部の1軸圧縮特性に関する基礎的研究

Abstract

"本研究では、鋼管によって補強された杭頭半剛接接合部の1軸圧縮特性について一連の実験的検討を行った。その結果、鋼管の埋込みが浅いほどひび割れは杭頭部に集中し、鋼管による割裂き効果が著しくなること、鋼管の埋込みが深くなると、鋼管による割裂き効果よりもコア部コンクリートに対する鋼管によるコンファインド効果が卓越するようになり、杭頭半剛接接合部の最大圧縮耐力および圧縮靭性は一般的に向上すること、鋼管とコンクリート間に界面処理を施して界面摩擦を低減させても、杭頭半剛接接合部の最大圧縮耐力はそれほど影響を受けないが、最大耐力後の耐荷性能は若干劣ること、などが明らかとなった。"

"In this study, the uniaxial compressive behaviors of semi-rigid-pile head joint reinforced by steel tube were investigated. The results obtained by the experiments can be summarized as follows: 1) The fracture zones are more concentrated in the top portion of concrete pile with decreasing the embed depth of steel tube，and the splitting effects for the concrete pile caused by the penetration of steel tube become remarkable，independently of the surface treatment between the steel tube and the concrete. 2) The uniaxial compressive strength and compressive ductilities improve with increasing the depth of embed steel tube, because the confined effects of concrete reinforced by the steel tube on the uniaxial compressive performance are distinguished with increasing the depth of embed steel tube，as compared with the splitting effects for the concrete caused by the steel tube. 3) The uniaxial compressive strength and the load carrying capacity in the large deformation range slightly decrease with reducing the surface friction between the steel tube and the concrete."