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A platform for research: civil engineering, architecture and urbanism
Behavior of CA-UHPC filled circular steel tube stub columns under axial compression
Abstract Ultra-high performance concrete with coarse aggregate filled steel tube (CA-UHPCFST) is a sustainable and high-performance structural form with high carrying capacity. This paper presents experimental and numerical investigations on the axial compressive behavior of circular CA-UHPCFST stub columns. Forty-four specimens were tested to determine the effects of concrete strength, steel fiber content, steel tube thickness, and steel yield strength on the axial compressive behavior. A finite element (FE) model was developed and validated for composite action analysis between steel tube and concrete core. The results show that the failure modes of CA-UHPCFST stub columns depend on confinement coefficient (ξ) categorizing as shear failure (ξ < 0.9) and bulge failure (ξ > 1.4). Correspondingly, as the confinement coefficient grows, the load-shortening curve after the ultimate resistance demonstrates three categories: descending, plateau, or hardening stage. The steel tube exhibits a prominent confinement effect on the CA-UHPC core, with a strength index ranging from 1.066 to 1.225; however, the enhancing effect is not as significant as that of the ordinary concrete-filled steel tubes. The incorporation of steel fiber can improve the ultimate resistance, but has a limited effect on strength index. By comparing the measured ultimate resistances to the predictions, the feasibility of current design codes for the prediction of load carrying capacity is evaluated, and a simplified model is proposed to predict the ultimate resistance of circular CA-UHPCFST stub columns under axial compression.
Highlights The effects of steel tube thickness, CA-UHPC strength, and steel fiber content are analyzed. The composite action between steel tube and CA-UHPC core is discussed. Steel fiber can improve the ultimate resistance of circular CA-UHPCFST stub column. A simplified model is proposed to predict the ultimate resistance of CA-UHPCFST stub column.
Behavior of CA-UHPC filled circular steel tube stub columns under axial compression
Abstract Ultra-high performance concrete with coarse aggregate filled steel tube (CA-UHPCFST) is a sustainable and high-performance structural form with high carrying capacity. This paper presents experimental and numerical investigations on the axial compressive behavior of circular CA-UHPCFST stub columns. Forty-four specimens were tested to determine the effects of concrete strength, steel fiber content, steel tube thickness, and steel yield strength on the axial compressive behavior. A finite element (FE) model was developed and validated for composite action analysis between steel tube and concrete core. The results show that the failure modes of CA-UHPCFST stub columns depend on confinement coefficient (ξ) categorizing as shear failure (ξ < 0.9) and bulge failure (ξ > 1.4). Correspondingly, as the confinement coefficient grows, the load-shortening curve after the ultimate resistance demonstrates three categories: descending, plateau, or hardening stage. The steel tube exhibits a prominent confinement effect on the CA-UHPC core, with a strength index ranging from 1.066 to 1.225; however, the enhancing effect is not as significant as that of the ordinary concrete-filled steel tubes. The incorporation of steel fiber can improve the ultimate resistance, but has a limited effect on strength index. By comparing the measured ultimate resistances to the predictions, the feasibility of current design codes for the prediction of load carrying capacity is evaluated, and a simplified model is proposed to predict the ultimate resistance of circular CA-UHPCFST stub columns under axial compression.
Highlights The effects of steel tube thickness, CA-UHPC strength, and steel fiber content are analyzed. The composite action between steel tube and CA-UHPC core is discussed. Steel fiber can improve the ultimate resistance of circular CA-UHPCFST stub column. A simplified model is proposed to predict the ultimate resistance of CA-UHPCFST stub column.
Behavior of CA-UHPC filled circular steel tube stub columns under axial compression
Wu, Fanghong (author) / Xu, Lihua (author) / Zeng, Yanqin (author) / Yu, Min (author) / Li, Ben (author)
2023-08-30
Article (Journal)
Electronic Resource
English
Behavior of innovative circular ice filled steel tubular stub columns under axial compression
| British Library Online Contents | 2018