Steel and Composite Structures

Volume 45, Number 5, 2022, pages 749-766

DOI: 10.12989/scs.2022.45.5.749

Experimental and numerical investigation on exposed RCFST column-base Joint

Ben Mou, Xingchen Yan, Qiyun Qiao and Wanqiu Zhou

Abstract

This paper investigates the seismic performance of exposed RCFST column-base joints, in which the high-strength steel bars (USD 685) are set through the column and reinforced concrete foundation without any base plate and anchor bolts. Three specimens with different axial force ratios (n = 0, 0.25, and 0.5) were tested under cyclic loadings. Finite element analysis (FEA) models were validated in the basic indexes and failure mode. The hysteresis behavior of the exposed RCFST columnbase joints was studied by the parametrical analysis including six parameters: width of column (D), width-thickness ratio (D/t), axial force ratio (n), shear-span ratio (L/D), steel tube strength (fy) and concrete strength (fc). The bending moment of the exposed RCFST column-base joint increased with D, fy and fc. But the D/t and L/D play a little effect on the bending capacity of the new column-base joint. Finally, the calculation formula is proposed to assess the bending moment capacities, and the accuracy and stability of the formula are verified.

Key Words

axial force ratio; column base joint; finite element analysis; parametric analysis; ultrahigh-strength steel bar

Address

Ben Mou:School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China Xingchen Yan:School of Civil Engineering, Qingdao University of Technology, Qingdao 266033, China Qiyun Qiao:College of Architecture and Civil Engineering, Beijing University of Technology, Beijing, 100124, P.R. China Wanqiu Zhou:School of Civil Engineering, Qingdao University of Technology, Qingdao 266033, China