bottom fiber

The test results show that, the flexural fatigue strength of polyacrylonitrile fiber reinforced concrete beams with bottom layer steel fiber is larger than the plain concrete 15.7%;

研究证明：底层撒布较长钢纤维的聚丙烯腈纤维混凝土梁的弯曲疲劳强度比素混凝土提高15.7%；