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APPENDIX L: FIRE TEST REPORT

DESCRIPTION OF TESTED SPECIMEN

A full-depth panel measuring 3 feet by 7 feet was tested to evaluate its fire resistance properties. The standard design of the panel uses fire-resistant resin, but no further protection was provided. It was tested without a wearing surface. See figure 93.

Photo. Test panel mounted on top of fire chamber.
Figure 93. Photo. Test panel mounted on top of fire chamber.

DESCRIPTION OF TEST SETUP

The test specimen was placed over the pilot scale combustion chamber, resting atop and perpendicular to two structural steel support beams (I-beams) spaced 24 inches on center (to be consistent with the proof-of-concept bridge in Allegany County). The support beams each measured 10.5 inches high with 4-inch-wide flanges and 0.25-inch web thickness. The surrounding exposed areas were enclosed with 1-inch-thick non-combustible gypsum shaft liner panels. Only a portion of the length was exposed to the fire over the combustion chamber.

Figure 94 shows the fire test chamber and the steel beams used to support the deck. This picture was taken after the test; note the peeled paint above the fire chamber.

. Photo. Support beams spaced at 2 feet.

The panel was loaded to a total superimposed load of 1,600 lb, nominally, using a water-filled steel tank, shown in figure 95, and instrumented with numerous thermocouples. Figure 96 and table 32 detail the placement of the thermocouples. The tank rested on the wood shown at the center of figure 93. This wood was dimensioned to reflect the standard AASHTO 10-inch by 20-inch footprint of a design vehicle.

Photo. 1,600-lb water tank used as concentrated load
Figure 95. Photo. 1,600-lb water tank used as concentrated load.

Photos. Placement of thermocouples on the test panel. Photos. Placement of thermocouples on the test panel.
Figure 96. Photos. Placement of thermocouples on the test panel.

Table 32. Details of thermocouple placement.
Thermocouple X, Y Location Z Location
TC01 on longitudinal axis, 42" from transverse axis top surface of deck panel
TC02 on longitudinal axis, 24" from transverse axis top surface of deck panel
TC03 10" from longitudinal axis, on transverse axis top surface of deck panel
TC04 10" from longitudinal axis, on transverse axis top surface of deck panel
TC05 on longitudinal axis, 24" from transverse axis top surface of deck panel
TC06 on longitudinal axis, 42" from transverse axis top surface of deck panel
TC07 on longitudinal axis, on transverse axis 1-3/8" from top surface of deck panel
TC08 on longitudinal axis, on transverse axis 3-1/2" from top surface of deck panel
TC09 on longitudinal axis, on transverse axis 4-5/8" from top surface of deck panel

TEST PROGRAM

The panel was loaded with the water tank before igniting the chamber and bringing the temperature to approximately 1,600 degrees Fahrenheit. The heat was applied for 20 minutes, at which time the test was stopped due to excessive smoke. Deflection measurements of the bridge deck panel, provided in table 33, were recorded at 1-minute intervals for the entire test duration. A technician sighted in on a leveling rod to measure the amount of deflection under load.

Table 33. Deflection measurements.
TC-797 BRIDGE COMPOSITES LLC K-1084 9/7/2012
Time (min) TC01 TC02 TC03 TC04 TC05 TC06 Grp Avg TC07 TC08 TC09
0.00 76 76 76 76 76 77 76 77 76 78
0.25 77 76 76 76 76 77 76 77 76 78
0.50 76 76 76 76 76 77 76 77 76 78
0.75 76 76 76 76 76 77 76 79 76 77
1.00 76 76 76 76 76 77 76 82 76 78
1.25 76 76 76 76 76 77 76 87 76 78
1.50 76 76 76 76 76 77 76 95 76 77
1.75 76 76 76 76 76 77 76 104 76 78
2.00 76 76 76 76 76 77 76 125 77 78
2.25 76 76 76 76 76 77 76 137 77 78
2.50 76 76 76 76 76 77 76 147 77 77
2.75 76 76 76 76 76 77 76 157 78 78
3.00 76 76 76 76 76 77 76 165 79 78
3.50 76 76 76 76 76 77 76 174 80 78
3.75 76 76 76 76 76 77 76 182 81 78
4.00 76 76 76 76 76 77 76 189 82 78
4.25 76 76 76 76 76 77 76 197 83 78
4.50 76 76 76 76 76 77 76 204 85 78
4.75 76 76 76 76 76 77 76 211 87 78
5.00 76 76 76 76 76 77 76 218 89 78
5.25 76 76 76 76 76 77 76 225 91 78
5.50 76 76 76 76 76 77 76 233 93 78
5.75 76 76 76 76 76 77 76 239 94 78
6.00 76 76 76 76 76 77 76 240 96 78
6.25 76 76 76 76 76 77 76 239 98 78
6.50 76 76 76 76 76 77 76 240 100 78
6.75 76 76 76 76 76 77 76 242 102 78
7.00 76 76 76 76 76 77 76 245 103 78
7.25 76 76 76 76 76 77 77 248 105 78
7.50 76 76 76 76 76 77 77 251 106 78
7.75 76 76 76 76 76 77 77 254 108 77
8.00 76 76 76 76 76 77 77 258 110 78
8.25 76 76 76 76 76 77 77 261 112 79
8.50 76 76 76 76 76 77 77 266 114 79
8.75 76 76 76 76 76 77 77 270 115 79
9.00 76 76 76 76 76 77 77 274 117 79
9.25 76 76 76 76 76 77 77 278 118 79
9.50 76 76 76 76 76 77 77 282 120 79
9.75 76 76 76 76 76 77 77 286 121 79
10.00 76 76 76 76 76 77 77 291 123 79
10.25 76 76 76 76 76 77 78 295 125 79
10.50 76 76 76 76 76 77 78 299 126 79
10.75 76 76 76 76 76 77 78 303 128 79
11.00 76 76 76 76 76 77 78 307 131 79
11.25 76 76 76 76 76 77 78 311 132 80
11.50 76 76 76 76 76 77 78 316 133 80
11.75 76 76 76 76 76 77 78 320 136 80
12.00 76 76 76 76 76 77 78 325 138 80
12.25 76 76 76 76 76 77 78 331 139 80
12.50 76 76 76 76 76 77 79 337 140 80
12.75 76 76 76 76 76 77 79 342 140 80
13.00 76 76 76 76 76 77 79 348 144 80
13.25 76 76 76 76 76 77 79 354 146 81
13.50 76 76 76 76 76 77 79 360 148 81
13.75 76 76 76 76 76 77 79 365 150 81
14.00 76 76 76 76 76 77 79 369 152 81
14.25 76 76 76 76 76 77 80 374 154 81
14.50 76 76 76 76 76 77 80 379 156 82
14.75 76 76 76 76 76 77 80 384 158 82
15.00 76 76 76 76 76 77 80 389 159 82
15.25 76 76 76 76 76 77 80 395 161 82
15.50 76 76 76 76 76 77 80 401 164 83
15.75 76 76 76 76 76 77 80 407 167 83
16.00 76 76 76 76 76 77 80 413 168 83
16.25 76 76 76 76 76 77 81 420 171 83
16.50 76 76 76 76 76 77 81 427 172 84
16.75 76 76 76 76 76 77 81 432 174 84
17.00 76 76 76 76 76 77 81 438 177 84
17.25 76 76 76 76 76 77 81 443 179 84
17.50 76 76 76 76 76 77 82 448 180 84
17.75 76 76 76 76 76 77 82 453 181 84
18.00 76 76 76 76 76 77 82 458 185 85
18.25 76 76 76 76 76 77 82 463 187 85
18.50 76 76 76 76 76 77 82 467 189 85
18.75 76 76 76 76 76 77 83 473 191 86
19.00 76 76 76 76 76 77 83 477 194 86
19.25 76 76 76 76 76 77 83 481 196 87
19.50 76 76 76 76 76 77 83 484 197 87
19.75 76 76 76 76 76 77 76 488 200 88
20.00 86 83 87 87 82 78 84 493 203 89

At the end of the test, the panel was still carrying load and generally structurally sound, although the resin on the bottom had burned off, exposing glass fiber. The following photos illustrate the condition of the specimen afterwards.

Photo. The test panel just after the test stopped. Note that the top surface kept cooler and ended up with little deterioration.
Figure 97. Photo. The test panel just after the test stopped. Note that the top surface kept cooler and ended up with little deterioration.

Photo. Specimen immediately after the test. Note the extent of damage on the bottom.
Figure 98. Photo. Specimen immediately after the test. Note the extent of damage on the bottom.

Photo. Close-up of the open end of the panel after the test.
Figure 99. Photo. Close-up of the open end of the panel after the test.

Photo. The glass fiber on the bottom has frayed due to burn-off of the resin matrix.
Figure 100. Photo. The glass fiber on the bottom has frayed due to burn-off of the resin matrix.

RESULTS

The deck panel survived 1,600-degree Fahrenheit temperatures relatively well. The top surface did not rise much higher than room temperature (~80 degrees Fahrenheit). Although the bottom surface suffered extensive damage, the multi-celled structure protected the upper part and reduced the spread of flame and high temperatures. The panel carried the full 1,600 lb. superimposed load with a maximum deflection of 5/16 inches. There was no crushing of the tubes observed, no excessive bending, and the panel was still functional at the end of the test.

Page last modified on May 18, 2012.
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000