The cross-shaped concrete-filled steel tube (CFST) is a new shape of column, which avoids convex corners and increases the interior area of the room. Cross-shaped CFSTs possess high bearing capacity, good seismic performance and efficient construction speed. In this study, cross-shaped stub CFSTs under axial loading were tested. The key parameter is the width/thickness ratio of the cross-section. Experiments revealed that local buckling could be delayed and section capacity enhanced by reducing the tube width/thickness ratio. Moreover, a finite-element model was established using the commercial program Abaqus to simulate the compressive performance of the specimens. The results were used to confirm the precision of the finite-element model. Further, a parametric study was completed to inspect the effects of the tube width/thickness ratio, concrete strength and steel yield strength on the mechanical properties of specimens. Relying on the constitutive theoretical model of restrained concrete, an equation is recommended to calculate the section capacity of cross-shaped CFSTs. Finally, the practical outcomes and the calculated outcomes obtained from different design codes (AISC, AIJ, EC4, CECS and GB) were compared. The comparison results revealed that all recommended design codes underrate the section capacity of cross-shaped CFSTs.
With the advancement in the concrete technology, the application of precast concrete elements in the buildings and road infrastructures is increasing very rapidly. One of such applications is the use of precast hollow concrete elements in the bridge construction. As the conventional steel reinforcement is highly susceptible to corrosion, the use of non‐corrosive reinforcement in precast hollow concrete piers and piles of bridges could be a good option for the durability of bridge structures., In this regard, hollow concrete columns reinforced with fiber‐reinforced polymer (FRP) have been considered as a potential solution to overcome the structural deterioration due to corrosion. In the past, limited studies have been carried out on hollow concrete columns reinforced with FRP, consequently, the behavior of such columns is not fully understood. Therefore, to comprehensively evaluate the behavior of hollow concrete columns for various design parameters, a finite element model (FEM) was developed in this study using the commercial tool “Abaqus”. The model was developed and verified based on the experimental results of studies conducted by two independent research groups on circular concrete columns. The proposed model well predicted the peak loads with an error less than 10% and the failure modes of the tested columns. The verified constitutive relation and establishing method were further employed to conduct parametric evaluations to observe the influence of different parameters, such as inner‐to‐outer diameter ratio, longitudinal reinforcement ratio, lateral reinforcement ratio, and concrete strength, on the behavior of hollow concrete columns. Parametric analyses show that reduced inner‐to‐outer diameter ratio and larger longitudinal or lateral reinforcement may lead to higher peak load and confined concrete strength. Finally, based on the experimental and FEM evaluations, the strength prediction equations were developed for the analysis and design of hollow concrete columns reinforced with GFRP bars.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.