1 Introduction
2 Experimental Details
Type | Size L × H×W (mm) | RTSF (kg/m3) | RTPF (kg/m3) | Steel mesh (kg/m3) | |
---|---|---|---|---|---|
Series 1 | Plain1 | 500 × 220 × 100 | 0 | 0 | 0 |
PF1 | 0 | 1 | 0 | ||
PF2 | 0 | 2 | 0 | ||
PF7 | 0 | 7 | 0 | ||
Series 2 | Plain2 | 500 × 200 × 200 | 0 | 0 | 123.3 |
SF40 | 40 | 0 | 61.5 | ||
SF40PF2 | 40 | 2 | 61.5 | ||
SF40PF5 | 40 | 5 | 61.5 |
2.1 Materials
Constituent | Amount (kg/m3) |
---|---|
Coarse aggregate (5 mm to 10 mm) | 1281 |
Fine aggregate (0 mm to 5 mm) | 734 |
Cement (CEM II 52.5) | 300 |
PFA | 99 |
Water | 168 |
Superplasticizer (polycarboxylate) | 4 |
2.2 Moisture Content and Compressive Strength
2.3 Fire Spalling Test Setup and Measurements
3 Results and Discussion
Specimens | Moisture content and strength results | Explosive spalling results | |||||||
---|---|---|---|---|---|---|---|---|---|
Age (days) | Moisture content (%) | Cube strength, fcu (MPa) | Occurrence of spalling | Spalling time (mm:ss) | Max spalling depth (mm) | Total weight loss (kg) | Concrete loss (kg) | ||
Series 1 | Plain1-1 | 28 | 2.2 | 69 | Yes | 00:30 | – | 0.505 | – |
Plain1-2 | 28 | 2.1 | 70 | No | – | – | 0.461 | – | |
Plain1-3 | 28 | 2.2 | 68 | Yes | 00:24 | – | 0.468 | – | |
PF1-1 | 28 | 2.9 | 65 | Yes (small) | – | – | 0.435 | – | |
PF1-2 | 28 | 2.9 | 68 | Yes | 01:00 | – | 0.901 | – | |
PF1-3 | 28 | 3.2 | 67 | Yes | 00:49 | – | 0.427 | – | |
PF2-1 | 28 | 3.2 | 68 | – | – | – | – | – | |
PF2-2 | 28 | 2.9 | 67 | No | – | – | 0.179 | – | |
PF2-3 | 28 | 3.0 | 67 | No | – | – | 0.222 | – | |
PF7-1 | 28 | 3.4 | 65 | No | – | – | 0.224 | – | |
PF7-2 | 28 | 3.3 | 65 | No | – | – | 0.257 | – | |
PF7-3 | 28 | 3.3 | 65 | No | – | – | 0.114 | – | |
Series 2 | Plain2-1 | 77 | 3.0 | 69 | Yes | 01:12 | 13 | 0.49 | 0.22 |
Plain2-2 | 77 | 3.0 | 71 | Yes | 00:41 | 17 | 0.94 | 0.67 | |
Plain2-3 | 77 | 3.0 | 70 | No | – | – | 0.25 | – | |
SFC-1 | 77 | 2.8 | 75 | No | – | – | 0.32 | – | |
SFC-2 | 77 | 2.8 | 71 | No | – | – | 0.34 | – | |
SFC-3 | 78 | 2.8 | 72 | No | – | – | 0.30 | – | |
SF40PF2-1 | 73 | 2.7 | 65 | Yes | 01:07 | 8 | 0.45 | 0.18 | |
SF40PF2-2 | 71 | 2.7 | 67 | No | – | – | 0.93 | – | |
SF40PF2-3 | 73 | 2.7 | 67 | No | – | – | 0.39 | – | |
SF40PF5-1 | 51 | 2.7 | 68 | No | – | – | 0.27 | – | |
SF40PF5-2 | 51 | 2.7 | 68 | No | – | – | 0.23 | – | |
SF40PF5-3 | 51 | 2.7 | 69 | No | – | – | 0.22 | – |
3.1 Moisture Content
3.2 Compressive Strength
3.3 Spalling Test Results
3.3.1 Series 1: Temperature Measurement
3.3.2 Series 2: Thermocouples
4 Thermal Analysis
Parameter | Value |
---|---|
Initial water content per m3 concrete | 48 kg/m3 |
Radiation view factor (RVF) for horizontal surfaces exposed to fire | 1.0 |
RVF for vertical surfaces exposed to fire | 0.5 |
RVF for surfaces between 0° and 45° exposed to fire | 0.667 |
Structural surface absorption factor, AB | 0.65 |
Fire emissivity factor, EF | 0.75 |
Structural surface’s emissivity factor, ES | 0.94 |