Study on Low Cycle Fatigue Failure in Civil Engineering Structural Members

为了获得土木工程结构中构件低周疲劳破坏的基本信息，研究了钢构件的应变行为，如应变范围、应变循环次数和应变速率。1）钢桥墩的应变行为分析了钢桥墩在地震荷载作用下屈曲部位的应变行为。作为本研究的结果，得到了地震时的应变大小和应变时程。分析了钢管混凝土（Concrete Filled Tube，简称CFT）构件中钢板的应变行为，并对钢管混凝土构件中钢板的应变行为进行了理论分析和试验研究。3）钢筋混凝土构件中钢筋的应变行为对钢筋混凝土构件中钢筋的应变行为进行了分析研究。根据分析结果，讨论了低周疲劳失效的可能性。

In order to obtain the fundamental information on the low cycle fatigue failure of structural members in civil engineering structures, strain behaviors such as strain range, the number of strain cycles and strain rate developed in the steel members were investigated.1) Strain behaviors in steel bridge piersThe strain behaviors at the buckling portion in steel bridge piers under earthquake loading were investigated analytically. As the results of this study, the magnitude of strain and the time history of strain during earthquake were obtained. Besides, the effects of constitutive law of steel on the strain behavior were analyzed.2) Strain behaviors in CFT (Concrete Filled Tube) membersThe strain behaviors in steel plate of CFT members were investigated both analytically and experimentally. The quantitative information on the strain field around the buckling portion was obtained.3) Strain behaviors in reinforced steel bar in RC membersThe strain behaviors in reinforced steel bar in RC members were investigated analytically. The possibility of low cycle fatigue failure was discussed based on the analysis results.