Circular hollow steel (CHS) members have been regarded as structural elements of choice for use in civil infrastructure. Despite the risk of seismic damage of steel structures during an earthquake due to its cyclic characteristics, studies on the cyclic strengthening of CHSs have been minimal. In the present study, a new finite element (FE) modelling approach is developed and applied to study the cyclic performance of carbon fibre reinforced polymer (CFRP) strengthened CHS specimens. The modelling techniques are first validated using results from the authors’ previous experimental work. A detailed parametric study is then carried out to evaluate the effects of CFRP bond length, CFRP layer numbers, ratio of thickness of CFRP to thickness of CHS, CHS member diameter-to-thickness ratio and steel grade on the cyclic performance of the CFRP strengthened CHS members. Results confirm the significant effects of these parameters on the cyclic performance of CFRP strengthened CHS members. The efficiency of CFRP strengthening increases with an increase in the ratio of the thickness of CFRP to the thickness of CHS and also with an increase in the diameter-to-thickness ratio of CHS specimens. Conversely, the efficiency of CFRP strengthening reduces with an increase in the steel grade. Moreover, the ultimate moment capacities obtained from the FE analyses of the bare and CFRP strengthened CHS specimens agree reasonably well with the theoretically predicted values.

圆形空心钢（CHS）构件已被视为民用基础设施中选择的结构元件。尽管由于其循环特性而在地震期间钢结构可能遭受地震破坏，但对CHS的循环强化的研究却很少。在本研究中，开发了一种新的有限元（FE）建模方法，并将其用于研究碳纤维增强聚合物（CFRP）增强的CHS样品的循环性能。首先使用作者先前实验工作的结果来验证建模技术。然后进行详细的参数研究，以评估CFRP键长，CFRP层数，CFRP厚度与CHS厚度之比的影响，CHS构件的直径/厚度比和钢种对CFRP增强的CHS构件的循环性能的影响。结果证实了这些参数对CFRP增强的CHS成员的循环性能的显着影响。CFRP强化的效率随着CFRP厚度与CHS厚度之比的增加以及CHS样品的直径/厚度之比的增加而增加。相反，随着钢种的增加，CFRP加固的效率会降低。而且，从裸露和CFRP加固的CHS样品的有限元分析获得的极限弯矩能力与理论预测值相当吻合。CFRP强化的效率随着CFRP厚度与CHS厚度之比的增加以及CHS样品的直径/厚度之比的增加而增加。相反，随着钢种的增加，CFRP加固的效率会降低。而且，从裸露和CFRP加固的CHS样品的有限元分析获得的极限弯矩能力与理论预测值相当吻合。CFRP强化的效率随着CFRP厚度与CHS厚度之比的增加以及CHS样品的直径/厚度之比的增加而增加。相反，随着钢种的增加，CFRP加固的效率会降低。而且，从裸露和CFRP加固的CHS样品的有限元分析获得的极限弯矩能力与理论预测值相当吻合。