Page 108 - Highway Engineering Handbook Building and Rehabilitating the Infrastructure

HIGHWAY LOCATION, DESIGN, AND TRAFFIC 91

TABLE 2.8 Minimum Radii for Design Speeds from 15 to 80 mi/h (24 to 129 km/h) and
Superelevation Rates to 6 Percent
e V 15 mi/h V 20 mi/h V 25 mi/h V 30 mi/h V 35 mi/h V 40 mi/h V 45 mi/h
d d d d d d d
(%) R (ft) R (ft) R (ft) R (ft) R (ft) R (ft) R (ft)
1.5 868 1580 2290 3130 4100 5230 6480
2.0 614 1120 1630 2240 2950 3770 4680
2.2 543 991 1450 2000 2630 3370 4190
2.4 482 884 1300 1790 2360 3030 3770
2.6 430 791 1170 1610 2130 2740 3420
2.8 384 709 1050 1460 1930 2490 3110
3.0 341 635 944 1320 1760 2270 2840
3.2 300 566 850 1200 1600 2080 2600
3.4 256 498 761 1080 1460 1900 2390
3.6 209 422 673 972 1320 1740 2190
3.8 176 358 583 864 1190 1590 2010
4.0 151 309 511 766 1070 1440 1840
4.2 131 270 452 684 960 1310 1680
4.4 116 238 402 615 868 1190 1540
4.6 102 212 360 555 788 1090 1410
4.8 91 189 324 502 718 995 1300
5.0 82 169 292 456 654 911 1190
5.2 73 152 264 413 595 833 1090
5.4 65 136 237 373 540 759 995
5.6 58 121 212 335 487 687 903
5.8 51 106 186 296 431 611 806
6.0 39 81 144 231 340 485 643

(Continued)