Compressive stress-strain relationship of fiber and nanosized material reinforced concrete in high temperature
Gao Danying1,2 Zhao Liangping1,2 Chen Gang1
1. Research Center of New Style Building Material and Structure, Zhengzhou University, Zhengzhou 450002, China；
2. Henan University of Engineering, Zhengzhou 451191, China
Abstract：Through the uniaxial compression tests on prism specimens in different temperatures which range from 25 to 800℃, the effects of temperature, steel fiber volume fraction, Nano-SiO2 and Nano-CaCO3 content on uniaxial compressive behavior of fiber and nanosized materials reinforced concrete (FNMRC) were investigated. The experimental results indicate that the peak stress, peak strain and initial elastic modulus of FNMRC decreased significantly with the temperature. The peak stress and peak strain of FNMRC in high temperature increase with the steel fiber volume fraction, while the initial elastic modulus decrease. With the increase of nanosized materials content, the peak stress, peak strain and initial elastic modulus of FNMRC in high temperature show a trend of increase. The influence of Nano-SiO2 on the compressive behavior of FNMRC is better than the Nano-CaCO3. Based on the test results, the stress-strain constitutive relationship and calculation methods of peak stress, peak strain and initial elastic modulus of FNMRC in high temperature are proposed, in which the effects of temperature, steel fiber volume fraction and nanosized materials content are taken into account.
