Research Article
Average Fracture Energy for Crack Propagation in Postfire Concrete
Table 2
Fracture energies for crack propagation.
| Specimen | Temperature | (Nm) | (m2) | (Nm−1) | (Nm) | (Nm) | (Nm) | (m2) | (Nm−1) | (Nm) | (m2) | (Nm−1) |
| WS1 | 20°C | 5.620 | 0.024 | 234.147 | 1.217 | 0.407 | 0.810 | 0.005 | 152.502 | 4.809 | 0.019 | 257.361 | WS2 | 11.608 | 483.664 | 1.575 | 0.388 | 1.187 | 0.003 | 350.795 | 10.421 | 0.021 | 504.972 | WS3 | 10.517 | 438.217 | 2.124 | 0.470 | 1.654 | 0.007 | 242.557 | 8.863 | 0.017 | 515.877 | WS4 | 5.265 | 219.394 | 0.994 | 0.314 | 0.680 | 0.006 | 107.537 | 4.586 | 0.018 | 259.384 | WS5 | 7.705 | 321.055 | 1.693 | 0.525 | 1.169 | 0.005 | 212.824 | 6.536 | 0.019 | 353.175 |
| Average | | 8.143 | | 339.295 | 1.521 | 0.421 | 1.100 | 0.005 | 213.243 | 7.043 | 0.019 | 378.154 |
| WS6 | 65°C | 7.666 | 0.024 | 425.907 | 1.791 | 0.535 | 1.255 | 0.007 | 281.835 | 6.411 | 0.017 | 480.239 | WS7 | 8.687 | 482.619 | 1.076 | 0.241 | 0.835 | 0.010 | 113.926 | 7.852 | 0.014 | 768.132 | WS8 | 8.779 | 487.745 | 1.475 | 0.509 | 0.966 | 0.007 | 208.612 | 7.813 | 0.017 | 602.385 | WS9 | 8.649 | 480.507 | 1.027 | 0.440 | 0.587 | 0.008 | 118.113 | 8.062 | 0.016 | 656.640 | WS10 | 9.402 | 522.360 | 1.419 | 0.733 | 0.686 | 0.005 | 210.596 | 8.716 | 0.019 | 614.693 |
| Average | | 8.637 | | 479.828 | 1.357 | 0.492 | 0.866 | 0.007 | 186.616 | 7.771 | 0.017 | 624.418 |
| WS11 | 120°C | 7.137 | 0.024 | 396.516 | 1.335 | 0.588 | 0.746 | 0.003 | 251.423 | 6.391 | 0.021 | 416.985 | WS12 | 9.321 | 517.822 | 1.475 | 0.511 | 0.964 | 0.005 | 178.684 | 8.357 | 0.019 | 616.201 | WS13 | 11.785 | 654.732 | 2.079 | 0.560 | 1.520 | 0.008 | 193.937 | 10.266 | 0.016 | 878.097 | WS14 | 6.218 | 345.463 | 1.044 | 0.312 | 0.732 | 0.007 | 98.944 | 5.486 | 0.017 | 455.357 | WS15 | — | — | — | — | — | — | — | — | — | — |
| Average | | 8.615 | | 478.633 | 1.483 | 0.493 | 0.991 | 0.006 | 180.747 | 7.625 | 0.018 | 591.660 |
| WS16 | 200°C | — | 0.024 | — | — | — | — | — | — | — | — | — | WS17 | 6.780 | 282.509 | 1.522 | 0.345 | 1.176 | 0.009 | 123.021 | 5.604 | 0.015 | 385.812 | WS18 | 5.163 | 215.135 | 1.556 | 0.525 | 1.031 | 0.007 | 146.955 | 4.132 | 0.017 | 243.300 | WS19 | 5.662 | 235.913 | 1.252 | 0.270 | 0.982 | 0.009 | 104.764 | 4.680 | 0.015 | 320.014 | WS20 | 8.854 | 368.937 | 1.828 | 0.365 | 1.463 | 0.010 | 145.364 | 7.391 | 0.014 | 530.467 |
| Average | | 6.615 | | 275.624 | 1.540 | 0.376 | 1.163 | 0.009 | 130.026 | 5.452 | 0.015 | 369.898 |
| WS21 | 300°C | 10.510 | 0.024 | 437.920 | 2.005 | 0.439 | 1.566 | 0.008 | 188.640 | 8.944 | 0.016 | 568.895 | WS22 | 14.675 | 611.467 | 3.546 | 0.820 | 2.726 | 0.007 | 364.621 | 11.949 | 0.017 | 723.160 | WS23 | 8.202 | 341.770 | 2.048 | 0.579 | 1.469 | 0.007 | 220.394 | 6.733 | 0.017 | 388.453 | WS24 | 13.539 | 564.120 | 3.065 | 1.081 | 1.984 | 0.005 | 404.514 | 11.555 | 0.019 | 605.107 | WS25 | 13.200 | 549.990 | 2.552 | 0.389 | 2.163 | 0.011 | 190.295 | 11.037 | 0.013 | 870.055 |
| Average | | 12.025 | | 501.053 | 2.643 | 0.662 | 1.982 | 0.008 | 273.693 | 10.044 | 0.016 | 631.134 |
| WS26 | 350°C | 13.765 | 0.024 | 573.540 | 2.689 | 0.511 | 2.179 | 0.010 | 211.652 | 11.586 | 0.014 | 845.346 | WS27 | 15.639 | 651.638 | 2.589 | 0.703 | 1.887 | 0.009 | 207.566 | 13.753 | 0.015 | 922.314 | WS28 | 12.420 | 517.489 | 3.827 | 0.919 | 2.908 | 0.010 | 317.145 | 9.512 | 0.014 | 664.527 | WS29 | 11.990 | 499.602 | 2.900 | 0.611 | 2.289 | 0.010 | 228.349 | 9.701 | 0.014 | 694.230 | WS30 | 10.905 | 454.375 | 2.796 | 0.475 | 2.320 | 0.011 | 216.312 | 8.585 | 0.013 | 646.739 |
| Average | | 12.944 | | 539.329 | 2.960 | 0.644 | 2.317 | 0.010 | 236.205 | 10.627 | 0.014 | 754.631 |
| WS31 | 400°C | 12.770 | 0.024 | 532.090 | 2.240 | 0.484 | 1.756 | 0.011 | 156.074 | 11.014 | 0.013 | 860.665 | WS32 | 9.526 | 396.932 | 2.678 | 0.656 | 2.022 | 0.009 | 207.133 | 7.504 | 0.015 | 516.314 | WS33 | 10.109 | 421.188 | 2.411 | 0.760 | 1.651 | 0.007 | 242.302 | 8.457 | 0.017 | 491.692 | WS34 | 14.374 | 598.926 | 3.638 | 0.918 | 2.720 | 0.006 | 401.879 | 11.654 | 0.018 | 668.062 | WS35 | — | — | — | — | — | — | — | — | — | — |
| Average | | 11.695 | | 487.284 | 2.742 | 0.705 | 2.037 | 0.008 | 251.847 | 9.658 | 0.016 | 634.184 |
| WS36 | 450°C | 14.677 | 0.024 | 611.530 | 3.255 | 0.779 | 2.477 | 0.009 | 277.088 | 12.200 | 0.015 | 809.983 | WS37 | — | — | — | — | — | — | — | — | — | — | WS38 | 11.579 | 482.451 | 3.284 | 0.669 | 2.615 | 0.009 | 303.750 | 8.964 | 0.015 | 582.382 | WS39 | 15.914 | 663.097 | 3.281 | 0.704 | 2.578 | 0.009 | 272.015 | 13.337 | 0.015 | 918.284 | WS40 | 16.291 | 678.790 | 3.847 | 0.532 | 3.315 | 0.011 | 292.743 | 12.976 | 0.013 | 1023.630 |
| Average | | 14.057 | | 608.967 | 3.417 | 0.671 | 2.746 | 0.010 | 286.399 | 11.869 | 0.014 | 833.570 |
| WS41 | 500°C | — | 0.024 | — | — | — | — | — | — | — | — | — | WS42 | 10.816 | 450.668 | 2.080 | 0.355 | 1.725 | 0.013 | 138.244 | 9.091 | 0.011 | 831.501 | WS43 | 11.434 | 476.413 | 2.890 | 0.743 | 2.146 | 0.008 | 272.496 | 9.288 | 0.016 | 576.031 | WS44 | 12.877 | 536.544 | 1.495 | 0.475 | 1.021 | 0.006 | 170.514 | 11.856 | 0.018 | 652.188 | WS45 | 10.838 | 451.571 | 2.720 | 0.308 | 2.412 | 0.013 | 186.562 | 8.426 | 0.011 | 785.892 |
| Average | | 10.496 | | 478.799 | 2.296 | 0.470 | 1.826 | 0.010 | 191.954 | 9.665 | 0.014 | 711.403 |
| WS46 | 600°C | 5.477 | 0.024 | 228.226 | 1.404 | 0.287 | 1.117 | 0.010 | 110.974 | 4.361 | 0.014 | 312.890 | WS47 | 9.481 | 395.057 | 2.526 | 0.460 | 2.066 | 0.010 | 213.423 | 7.415 | 0.014 | 517.849 | WS48 | 12.941 | 539.225 | 2.621 | 0.389 | 2.232 | 0.014 | 155.808 | 10.709 | 0.010 | 1107.140 | WS49 | 7.968 | 331.988 | 1.514 | 0.635 | 0.879 | 0.010 | 115.238 | 7.088 | 0.014 | 491.494 | WS50 | 6.554 | 273.074 | 1.749 | 0.773 | 0.976 | 0.009 | 151.878 | 5.578 | 0.015 | 342.831 |
| Average | | 8.484 | | 353.514 | 1.963 | 0.509 | 1.454 | 0.011 | 149.464 | 7.030 | 0.013 | 632.922 |
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