When replacing welded-wire reinforcement with micro- or macro-synthetic or steel fibers, how is the “equivalent dosage” of fibers determined?

The equivalent dosage of fibers to replace embedded steel reinforcement needs to be evaluated by the design engineer for the specific project or application. Guidance for the designer is available in ACI 506R-05, “Guide to Shotcrete,” and ACI 506.1R-08, “Guide to Fiber-Reinforced Shotcrete.”