Double Edge Wedge Splitting Test to Characterize the Design Postcracking Parameters of Fiber-Reinforced Concrete Subjected to High Temperatures

摘要

The determination of the postcrack tensile properties of steel fiber-reinforced concrete (SFRC) after exposure to elevated temperatures is a current methodological challenge. The objective of this research is to evaluate the applicability of the double edge wedge splitting (DEWS) test to characterize the postcrack tensile properties of SFRC after exposure to elevated temperatures. Results show that the DEWS test has reduced scatter and facilitates the interpretation of results with diminished frictional interaction between the apparatus and the specimen. The results in terms of coefficient of mechanical degradation were comparable to those obtained by bending tests in literature, which highlights the suitability of the DEWS test to be adopted in future researches and guidelines. The postcrack tensile properties were not significantly affected up to ~300°C and a linear reduction ratio was verified with the increase in temperature. Additionally, the constitutive model proposed may reproduce the effect of temperature on the tensile stress-strain behavior of the SFRC and is a valuable input for hygro-thermo-mechanical numerical models oriented to simulate the mechanical behavior of structures made with SFRC.