Title:
Steel Fiber Shotcrete -A Laboraty Study
Author(s):
Dudley R. Morgan
Publication:
Concrete International
Volume:
3
Issue:
1
Appears on pages(s):
70-74
Keywords:
deformed reinforcement; fibers; fle,,u,
strength; impact strength; modulus of elasticity; St, Crete; tests.
DOI:
Date:
1/1/1981
Abstract:
A laboratory study was carried out to assess the , performance of hooked steel fiber in dry shotcrete mixes. A total of five different shotcrete mixes were investigated: (a) IO mm aggregate plain control Shot Crete; (b) IO mm aggregate + 1 .O percent steel fi& shotcrete; (c) 10 mm aggregate + 1 .O percent steel fiber shotcrete; (d) 10 mm aggregate + 1.5 percent steel fiber shotcrete; and (e) sanded + 1.0 percer,t steel fiber shotcrete. The mixes were all supplied as dry, premixed, bagged materials. All mixes were readily applied to test panels using a premoisturizer and a shotcrete machine. There were no significant problems of ball. ng or blockages in the equipment of segregation in the test panels, even at the 1.5 percent, 198 lblcu Yd (117.5 kg/m3) steel fiber concentration [mix (d) described above]. Each mix was tested according to recommended ACI or ASTM test procedures for shot-Crete. The following hardened shotcrete properties were determined: (1) compressive strength; (2) modulus of rupture (flexural strength); (3) toughness index; (4) impact strength; and (5) boiled absorption and air voids.