Numerical Study on Mechanical Properties of Steel Fiber Reinforced Concrete by Statistical Second-order Two-scale Method

The present study aims to evaluate the mechanical properties of steel fiber reinforced concrete (SFRC) by the statistical second-order two-scale (SSOTS) method. At first, the representation for microstructure of SFRC is described by a concept of statistical screen. According to the microstructure representation, the SSOTS method is displayed in a concise way. This method is on the basis of asymptotic expansion homogenization and Monte Carlo method, and can calculate the local strain and stress field through the two-order displacement solution. As the classical homogenization method, the expression of homogenized elastic modulus is derived analytically. Then combined with the appropriate strength criterion and correspondence principle, the homogenized strength and viscoelastic properties of SI-RC are obtained respectively. The validity of the SSOTS method is confirmed by the comparison between numerical results and the available experiment data. Results show that the SSOTS method is effective to evaluate the elastic, strength and viscoelastic properties of SFRC. In addition, the influence of distribution of steel fibers on the macroscopic mechanical properties of SFRC is discussed.