The influence of anti-cracking agent and fibers on the properties of face slab concrete

Abstract

The influence of anti-cracking agent, PVA fibers and basalt fibers single or composite doping on the compressive, tensile, dry shrinkage deformation and early crack resistance of face slab concrete was investigated.The result showed that the addition of 12% anti-cracking agent result ed in a decrease in the compressive strength, compressive modulus, axial tensile strength and ultimate tensile value of the face slab concrete at various ages, but it was beneficial for reducing the dry shrinkage deformation. The dry shrinkage deformation of the face slab concrete after 180 days was reduced by 22×10^-6. And no cracks were found in the flat plate cracking test. Adding PVA fibers(0.9 kg/m³) or basalt fibers(2.5 kg/m³) is beneficial for improving the properties of face slab concrete, with a 7.0% and 9.2% increase in 28 day axial tensile strength, respectively. Meanwhile, in the plate cracking test, the cracking time is delayed, the number of cracks is reduced, and the crack area is reduced. When the anti-cracking agent is mixed with PVA fibers or basalt fibers, their effects on the compressive and tensile properties of the face slab concrete compensate for each other, but they have a synergistic effect on improving the dry shrinkage deformation and early crack resistance performance. The dry shrinkage deformation of the face slab concrete after 180 days can be reduced by about 30×10^-6. And no cracks were found in the flat cracking test.

Keywords

face slab concrete / anti-cracking agent / PVA fibers / basalt fibers / concrete properties