# Shear and Flexural Behavior of RC Columns with Rectangular Hollow Cross-Sections Under Cyclic Loading

## TL;DR

This study examines how reinforced concrete columns with hollow rectangular shapes behave during earthquakes, finding they can perform well if designed properly.

## Contribution

The study introduces insights into the seismic performance of hollow RC columns, showing minimal impact on flexural strength and improved shear estimation methods.

## Key findings

- Flexure-dominated hollow RC columns showed stable seismic performance even with reduced shear span ratios.
- Hollow cross-sections had minimal effect on flexural strength and bar strain distribution.
- Using an equivalent cross-sectional area improved shear strength estimation accuracy.

## Abstract

This study investigates the seismic behavior of reinforced concrete (RC) columns with hollow rectangular cross-sections through experimental testing and analytical evaluation. A series of hollow-sectioned column specimens with different shear span ratios and failure modes were tested under cyclic lateral loading to examine their flexural and shear performance. The results demonstrated that flexure-dominated columns exhibited stable load-deformation responses and sustained seismic performance, even with the reduced shear span ratio. The experimental results also showed that the presence of the hollow cross-section had minimal influence on flexural strength and bar strain distribution. The shear strength of RC columns with hollow cross-sections tended to be underestimated by the conventional equation; however, improved accuracy was achieved by applying an equivalent cross-sectional area in the calculation. A nonlinear finite element analysis successfully reproduced the flexural load-deformation response of the specimens. While some discrepancies were observed in the shear-dominated cases, the analytical model provided conservative estimates under positive loading. These findings provide new insights into the seismic design of RC columns with hollow cross-sections, highlighting their potential applicability in building structures when flexural and shear behaviors are properly considered.