Man-Tai Chen

TL;DR: In this article, a stress-strain model was developed to better understand and simulate the behaviour of FRP-confined concrete, which consists of the following three main components: (1) a hoop strain equation elaborated from the authors' previous study on steel-constrained concrete columns for application to FRP confined concrete; (2) a modified confined concrete model considering stresspath of confining stress (or history of hoop strain); (3) Interaction between FRP and concrete.

TL;DR: In this paper, a theoretical stress-strain model for concrete-filled steel-tube (CFST) columns was developed to better understand and simulate the behavior of CFST column, which consists of the following four main components: (1) Interaction between steel tube and concrete taken into account the de-bonding effect; (2) an accurate hoop strain equation; (3) a passively confined concrete model considering stress-path dependence; (4) a three-dimensional stress-strain model for steel tube.

TL;DR: In this paper, a database collecting 28 CFFT columns test results is assembled for establishing a new stress-strain model that comprises the following 4 parts: (1) A model of hoop strain set up by the authors taking into account the effects of concrete splitting cracks; (2) An adjusted constitutive model of actively confined concrete incorporating confining stress path dependent effect; (3) Bi-axial stress model of FRP tube; (4) a model addressing the compatibility condition of concrete and fiber-reinforced polymer (FRP) tube.

TL;DR: In this article, tie bars, steel rings and steel spirals are used to increase the confinement effect of UHSCFST columns, and a series of uni-axial compression test has been conducted to study the behavior of externally confined columns.

TL;DR: In this article, modifications on the Direct Strength Method and the Continuous Strength Method are proposed, which are shown to improve the accuracy of the design strength predictions. But there is no codified design rule for elliptical hollow section compression members.