挤出成型工艺生产玻璃纤维增强水泥板(GFRC)时,纤维在螺旋推挤力和速度剪力的作用下,大部分纤维能在挤出方向上形成定向排列,轴拉强度相对较高.而垂直于挤出方向的纤维分布相对较少,力学性能也相对较差.试验结果表明,当纤维含量较低时,绝大部分纤维沿挤出方向分布,此时,平行挤出方向的轴拉强度远大于垂直挤出方向.纤维掺量较高时,垂直挤出方向上的纤维分布量大大增加,相应的轴拉强度几乎与平行挤出方向相等.此外,存在一个纤维掺量饱和点,超过此掺量,平行纤维方向的轴拉强度不再随掺量的增加而提高,但有利于改善GFRC板的韧性和轴拉破坏形式.
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