Influence of autogenous cracking on the durability of repairs by cement-based overlays reinforced with metal fibres

Title: Influence of autogenous cracking on the durability of repairs by cement-based overlays reinforced with metal fibres
Author(s): A. Turatsinze, H. Farhat, J.-L. Granju
Paper category : journal
Serial title: Materials and Structures
Abreviated Serial title: Mater. Struct.
ISSN: 1359-5997
Publisher: RILEM Publications SARL
Volume: 36
Issue: 264
Issue date: 2003-12-01
Publication year: 2003
Pages: 673 - 677
Total Pages: 5
Nb references: 13
Language: English

Abstract: The focus of this research is a better understanding of the structural behaviour and durability of metal fibre reinforced concrete repairs.
A total of 9 overlaid specimens, with the overlay on the tension face, were tested under deflection controlled three point bending.
Three types of overlays were tested: one made with plain mortar (M0) and two with fibre-reinforced mortars (M1 and M2).
Mortar M1 was reinforced with 40 kg.
m(-3) of 30-mm-long hooked-ends steel fibres.
Mortar M2 was reinforced with 20 kg.
m(-3) of 30-mmlong amorphous metal fibres.
During the preparation of the repair layer, the upper face of the repair was notched at mid-length using a shaped PVC plate fitted to the mould.
Because of the specimen curing conditions, the associated drying shrinkage had initiated a crack at the notch tip before the mechanical tests started.
In such conditions, the debonding mechanisms are quite representative of the debonding of in situ repairs.
It is shown that the debonding of fibre-reinforced repairs is significantly delayed in comparison with plain repairs.
This better behaviour is due to the fibres' ability to restrain the crack opening within the repair layer, which in turn helps to reduce the stresses at the base-repair interface.

Online publication: 2003-10-27
Classification: Scientific Reports
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/13898