Section Width (feet) | |||||||||
12 | 14 | 16 | 12 | 14 | 16 | 12 | 14 | 16 | |
Support Spacing (feet) | |||||||||
6 | 6 | 6 | 8 | 8 | 8 | 10 | 10 | 10 | |
Support Loading (pounds per pier) | |||||||||
3200 | 3700 | 4250 | 4250 | 4950 | 5650 | 5300 | 6150 | 7050 | |
Soil's Load- Bearing Capacity (lbs/ft2) | Footing Area (square inches) | ||||||||
1000 | 461 | 533 | 612 | 612 | 713 | 814 | 763 | 886 | 1015 |
1500 | 307 | 355 | 408 | 408 | 475 | 542 | 509 | 590 | 677 |
2000 | 230 | 266 | 306 | 306 | 356 | 407 | 382 | 443 | 508 |
3000 | 154 | 178 | 204 | 204 | 238 | 271 | 254 | 295 | 338 |
4000 | 144 | 144 | 153 | 153 | 178 | 203 | 191 | 221 | 254 |
Ill. Admin. Code tit. 77, pt. 870, tbl. B