Abstract: Cement mortar was reinforced by mixing with blast furnace slag fiber to enhance the mechanical properties of cement mortar materials and improve the utilization rate of mineral resources. The effects of the content and length of furnace slag fibers on the strength characteristics of reinforced mortar specimens were studied via unconfined compression tests. The results manifest that with the increase of slag fiber content, the unconfined strength of cemental mortar improves; but such improvement attenuates notably when the slag fiber content exceeds 0.3%. Furthermore, slag fibers with lengths of 5 mm and 10 mm were mixed for comparison. Given the same fiber content, long fiber generates a strengthening effect 1.3-1.5 times that of short fiber. Microscopic morphology observation demonstrates that the addition of furnace slag fibers to cement mortar can improve the adhesion between particles, forming a “bridging effect”, thus finally enhancing the strength and toughness of cement mortar.

Key words: slag fiber, cement mortar, unconfined compression test, strength, microstructure