ハイブリッドFRP引抜成形山形材の圧縮耐荷力に関する研究

Abstract

本研究では，腐食した鋼橋における取替または補強部材として開発したハイブリッドFRP引抜成形山形材の圧縮耐荷力特性を明らかにすることを目的として，対象山形材の圧縮耐荷力実験および圧縮耐荷力解析を実施し，弱軸回りまたは強軸回り回転自由の境界条件のもと，対象山形材の局部座屈および全体座屈性状を把握し，圧縮耐荷力の基礎データを取得した．全体座屈が支配する長柱領域において，強軸回り回転自由の条件では，強軸回りの曲げとねじれが連成する曲げねじれ座屈モードとなり，弱軸回り回転自由の条件では，弱軸回り曲げの全体座屈となった．短柱領域では，どちらの境界条件でも局部座屈が圧縮強度を支配した．それらの結果から，対象山形材の耐荷力曲線は，局部座屈強度と弱軸回りの全体座屈強度をもとに作成できる可能性が明らかとなった．

This study conducted compression tests and numerical analyses of pultruded hybrid FRP angle section which has been developed to be used for replacement member and reinforcement member for corroded steel bridges, in order to understand global and local buckling characteristics and to obtain compressive strength data. As a result, the angle section with a large slenderness ratio when the rotation around the strong axis is free shows a flexural-torsional buckling mode with a twisting of section, and compressive strength of flexural-torsional buckling is closer to the flexural buckling strength about the weak axis than that about the strong axis. Since the angle section with a small slenderness ratio is controlled by the local buckling, the compressive strength of the angle section in this study may be determined based on the local buckling strength and the global buckling strength about the weak axis.