Polypropylene Fiber Effect on Flexural Strength, Toughness, Deflection, Failure Mode and Microanalysis of Cementitious Backfills under Three-Point Bending Conditions

Cemented tailings backfill (CTB) is continually practiced in a large number of metallic mines for re-filling underground ore extraction areas. Re-filling these areas can boost the security mining teams during construction. Hence, CTB’s durability/ductility extremely vital to ensure safety entire mine. In this study, layered-fiber-reinforced CTB (LFR-CTB) was manufactured using polypropylene fiber (PPF) increase strength and flexibility backfilling. The bending features LFR-CTB specimens were explored through three-point test SEM microanalysis. Test findings pointed out that flexural 14-day-cured without delamination with cement showed ratio 1:4 largest among others. Residual greater than those delamination. Accumulating effectively improved features. CTBs presented average modulus values. LFR-CTBs toughness index values ordinary specimens. Adding facilitated progress post-peak rigidity. containing high-fiber dimensional height have excellent properties. damage mode all chiefly tensile damage. overall bonding presence interlayer interfaces outstanding, not affecting their performance. Ettringite CSH gels found be key hydration materials. addition filling has an inhibitory impact on extension cracks occurring within Finally, study’s consequence deliver technical guideline reference order reveal LFR-CTB’s enhancement mechanism industrial applications.