EXPERIMENTAL STUDY ON THE EFFECTS OF STRAIN RATE AND SHORT FIBER CONTENT ON TENSILE BEHAVIOR OF TR-HDC

In order to study the uniaxial tensile behaviors of textile-reinforced high ductility concrete (TR-HDC) with different strain rates and short fiber contents, 25 groups of TR-HDC thin-plate specimens were designed to load through uniaxial tensile tests. The effects of strain rate (10⁻⁵ s⁻¹ ~ 10⁻¹ s⁻¹) and short fiber content (0% ~ 2%) on the cracking mode, failure mechanism and tensile strength of TR-HDC were studied. The results showed that: TR-HDC had the multi-cracking characteristics under uniaxial tensile load. With the increase in strain rate, the crack spacing of the specimens increased slightly. A higher content of short fibers led to more stable multi-cracking mode. The increase of strain rate and short fiber content can significantly improve the interfacial properties and inhibit the slipping failure of textile. With the increase in strain rate, the mechanical properties of TR-HDC showed strain rate sensitivity. Moreover, its cracking and peak strength showed a significant growth trend with the increase of the short fiber content. Based on the linear logarithmic relationship and multi-factor coupling, the proposed prediction model can unify the static and dynamic tensile strength of TR-HDC, which provides a theoretical basis for its engineering application.