Behavior and design of steel-tubed-reinforced-concrete columns reinforced with non-through section steel

Abstract

This paper presents an experimental and analytical study on the seismic behavior and load-carrying capacity of the steel-tubed-reinforced-concrete (STRC) column reinforced with non-through section steel. A total of 8 columns with different built-in section steel lengths and varying axial compression ratios were tested under low-period cyclic load. The damage features, hysteresis curves, and steel tube strain of the specimens were analyzed, respectively. The effects of built-in length of section steel and axial compression ratio on seismic performance were discussed. The results indicated that: the STRC columns are mainly subjected to compression-bending failure mode. Within a critical built-in length range of section steel, the section steel-concrete transition section is damaged, and the seismic performance and bearing capacity increase significantly with the increase in section steel length. When the critical value is exceeded, the column root section is damaged, and the performance of the specimens is no longer improved. The damage position and lateral load capacity of the STRC column with non-through section steel are determined by the critical length and the bearing capacity of the two typical sections. Based on experimental and finite element analysis, the calculation methods for the compression and bending capacity of two typical sections are given, and the calculation formula for the critical length of section steel is provided.