【摘要】 乱向分布纤维增强效果不如顺向排列纤维。常用方向效能系数将乱向纤维向顺向纤维进行折算。对于二维分布的纤维，其方向效能系数为０．６３７已被人们所认可。对于三维乱向分布的纤维，方向效能系数常用值为０．４０５和０．５，这两个值目前均普遍采用。纤维方向效能系数应仅与分布状态有关，不应随着推导过程的不同而有所不同。通过对上述两参数推导过程的审查，认为０．５为三维乱向分布纤维的方向效能系数的理论值，而０．４０５则为误导的结果。更多还原

【Abstract】 Reinforced effect of randomly distributed steel fibers is not as good as regularly distributed ones Randomly distributed fibers are usually calculated by direction coefficient As for steel fiber of two dimensions, people knew that its direction coefficient is 0 637,To randomly distributed steel fiber of three dimensions, its direction coefficient is often 0 405 and 0 5 The two values are widely used at present Fiber direction coefficient only has something to do with distribution state, nothing with calculating process Their calculating process of the two parameters were checked in this paper and the theoretical value of randomly distributed fibers′ direction coefficient of three dimensions is defined as 0 5, but 0 405 is a mistaken result更多还原