Improving seismic performance of structural systems via reinforcing column bases

ABSTRACT

One of the conventional methods of rehabilitation is to strengthen beams and braces buried inside floors and walls, respectively. In structural systems, plastic hinge and local buckling may form in column bases, which their early formation can result in strength and stiffness degradation and finally earlier fracture. Accordingly, this study proposes to reinforce column bases to 1) improve strength, stiffness, and energy dissipation of Special Concentrically Braced Frames (SCBFs) and Special Moment Resisting Frames (SMRFs), and 2) delay plastic hinge formation in column bases. Six SCBFs and six SMRFs were considered into two different groups (models with conventional and reinforced column bases) and simulated in ABAQUS. The findings indicated that reinforced column bases can increase strength, stiffness, and energy dissipation capacity around 67%, 93%, and 67%, respectively. Moreover, the results showed that reinforcing column bases moved local buckling and plastic hinge away from column bases and yielding and local buckling initiation occurred in the columns at roof drifts which were respectively 1.48 and 1.47 times of those in models with the conventional column bases.

KEYWORDS:

• Column bases
• local buckling
• plastic hinge
• reinforcement of column bases

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Ilam University [Grant No. IRILU-En-000049-21-04].