纤维混凝土构件在温缩荷载作用下的非线性随机有限元分析

Nonlinear Monte-Carlo FEM Simulation on Fiber Concrete under Temperature Drop Load

为研究纤维对混凝土构件的抗温缩能力,利用Moelands-Reinhardt(M-R)软化本构关系,采用非线性随机有限元法,即Monte-Carlo法分别对素混凝土和纤维混凝土构件的温降收缩过程进行分析.分析结果表明:纤维的存在可提高混凝土抗拉极限状态温降值,掺加超细纤维对混凝土的增强效果不明显;超细纤维依靠其韧性提高了混凝土的抗拉极限温降值和构件薄弱区域的抗拉能力,减小了由材料性质不均而造成脆断的可能性,在整体上延缓了构件到达抗拉极限状态的过程.

Based on nonlinear Monte-Carlo stochastic finite element method and Moelands-Reinhardt constitutive relationship, fiber concrete specimens under temperature drop load were analyzed. The statistic results indicate that fibers can improve the ability to resist temperature drop load, although they cannot dis- tinctly improve concrete specimen＇s tensile strength. The analysis on fiber concrete specimens represents that fibers enhance the concrete＇s fracture energy and defer the crack process of concrete by relax the shrink of surrounding concrete body.