Abstract： Interfacial imperfection, commonly existing in many in-service CFST structures, is one of the most significant factors that influence the workability of concrete filled steel tube (CFST). In this study, the flexural capacities of circular CFST components with different ranges of interfacial imperfection were tested. The influences of imperfection range on the failure mode, flexural capacity, mid-span deflection and surface stress of steel tube were analyzed. The damage of the core concrete during the loading process of the specimen was monitored and detected by using acoustic emission technique, and the influence rules of interfacial imperfection on the damage of concrete and the flexural capacity of the specimen were analyzed. Based on the modification of experimental results, the finite element analysis model was established to study the influence rules of the factors such as sectional steel ratio, strength of core concrete and range of interfacial imperfection on the flexural rigidity of CFST members. The results indicate that the effects of steel ratio and range of interfacial imperfection on flexural rigidity of CFST members are opposite, that is, the higher the steel ratio is, the lower the reduction influence of flexural rigidity from interfacial imperfection is; similar effects of core concrete strength and interfacial imperfection range on flexural rigidity can be observed, that is, the higher the core concrete strength is, the higher the reduction influence of flexural rigidity from interfacial imperfection is. In addition, an empirical formula of determining the reduction factor of flexural rigidity under different interfacial imperfection range was derived.
刘明辉 韩 冰 朵君泰. 界面缺陷对钢管混凝土受弯构件抗弯性能影响研究[J]. 土木工程学报, 2019, 52(6): 55-66.
Liu Minghui Han Bing Duo Juntai. Investigation on the effect of interface imperfection on the flexural behaviors of concrete filled steel tubular bending members. 土木工程学报, 2019, 52(6): 55-66.
