Abstract: Municipal Fibers were used to improve phosphogypsum-based cementations material (PGS) anti-cracking ability. The influence of adding fiber was investigated by measuring the impact work, flexural strength, freeze-resistance, and the microscopy of fracture surface. Results showed that fiber could prevent PGS from cracking obviously better than both mineral fiber and glass fiber. The impact work and the flexural strength of PGS with 0.7% fiber cured at 20℃ （R.H.≥90）for 28d were increased by 389.5% and 50.6% respectively; after 15 freeze-thaw cycles, the impact work, flexural strength and mass loss rate of cementitious material with 0.7% fiber were decreased by 87.4%, 71.4% and 50.4% respectively. The fiber distributed in the matrix of hardened PGS offered a bridging function notably because of three-dimensional network structure.
