Due to the change in the use of function or the addition of new equipment, some problems have occurred in the used portal steel frames, including increased load and unsatisfactory bearing capacity. Therefore, the used portal steel frames need to be reinforced and improved. As a safe, reliable, economical, and convenient strengthening method, the external prestressing strengthening technology is often used to reinforce the portal frame. In this paper, in order to avoid damage to the original structure in the strengthening process due to welding, drilling and other connection methods, the sickle anchoring joint was applied in the external prestressing strengthening of portal frame. The principle of lever was used to fix sickle anchoring joint on the lower flange of the steel beam to achieve effective anchoring of the steel cable and steel beam. The FEM simulation was used to study the stress characteristics of the sickle anchoring joint, including equivalent stress, contact status, etc. In addition, in practice, the joint was used for the strengthening of portal frame. The strain at different parts of rigid frame and the deflection in mid-span were measured in the experiment. The experimental and simulation results were compared to verify the effectiveness of joint. The study showed that the sickle anchoring joint had the advantages of simple structure, clear force, high safety and effectiveness. Thus the sickle anchoring joint can be applied to the external prestressing strengthening of the portal frame.

由于功能用途的改变或新设备的增加，使用过的门式钢框架出现了一些问题，包括增加的载荷和不令人满意的承载能力。因此，需要对用过的门式钢框架进行加固和改进。作为一种安全，可靠，经济，方便的加固方法，通常采用外部预应力加固技术来加固门框。为了避免在加固过程中由于焊接，钻孔等连接方式而损坏原始结构，将镰刀形锚固接头应用在门框的外部预应力加固中。使用杠杆原理将镰刀形锚固接头固定在钢梁的下部法兰上，以实现钢缆和钢梁的有效锚固。有限元模拟用于研究镰刀形锚固接头的应力特性，包括等效应力，接触状态等。此外，在实践中，该接头用于加强门框。实验测量了刚性框架不同部位的应变和中跨挠度。比较了实验结果和仿真结果，以验证接头的有效性。研究表明，镰刀式锚固关节结构简单，受力清晰，安全性高，有效性高。因此，镰刀形锚固接头可应用于门架的外部预应力加强。该接头用于加强门框。实验测量了刚性框架不同部位的应变和中跨挠度。比较了实验结果和仿真结果，以验证接头的有效性。研究表明，镰刀式锚固关节结构简单，受力清晰，安全性高，有效性高。因此，镰刀形锚固接头可应用于门架的外部预应力加强。该接头用于加强门框。实验测量了刚性框架不同部位的应变和中跨挠度。比较了实验结果和仿真结果，以验证接头的有效性。研究表明，镰刀式锚固关节结构简单，受力清晰，安全性高，有效性高。因此，镰刀形锚固接头可应用于门架的外部预应力加强。高安全性和有效性。因此，镰刀形锚固接头可应用于门架的外部预应力加强。高安全性和有效性。因此，镰刀形锚固接头可应用于门架的外部预应力加强。