| INTRODUCTION |
In
April 2001 Krosaki Harima Corporation (Japan) were commissioned
by the Japan Highway Board to investigate the performance
of Fibre Reinforced Concrete (FRC) at high temperatures
to provide information relating to deterioration due to
spalling in tunnel fires.
The specimens prepared were as follows:
| No. |
Specimen |
Description |
1 |
Plain Concrete |
NA |
2 |
Barchip M Synthetic Fibre |
7 kg /m3 |
3 |
Steel Fibre |
40 kg /m3 |
|
EXPERIMENTAL
PROGRAM |
The
test method, developed in the Netherlands, exposed all
samples to the Dutch RWS fire curve with an extreme fire
loading of 1350oC for 2 hours.
Concrete specimens of nominal 32 MPa and dimensions of 1.0m x 1.0m x 0.3m were
prepared to simulate sections of a tunnel lining.
|
RESULTS
|
Thermocouples
(in accordance with JIS C1602) were installed in each concrete
section at the surface, at 50 mm depth, 100 mm depth and
the rear of the panel to provide temperature profile data
during the 2 hour exposure.
 |
PLAIN CONCRETE
Fire Damage- 108mm Depth |
BARCHIP
M
Fire Damage- 36mm Depth |
STEEL
FIBRE
Fire Damage- 118mm Depth |
|
| |
|
| CONCLUSION |
The
Barchip fibre reinforced concrete specimens exhibited lower
temperatures at all depths and subsequently
suffered far less depth of wear due to temperature
related explosive spalling when compared to plain or steel
reinforced concrete.
It is theorised that the melting of Barchip fibres at
the concrete surface creates channels
for expanding steam gases to escape thereby leaving a
greater depth of the concrete element intact.
|
| |
This
information has been provided as a guide to performance
only, for specific and supervised conditions. The user
is advised to undertake their own evaluation and use the
services of professionals to determine product suitability
for any particular project or application prior to commercial
use.
|