Department of Transportation

Design Control for Sag Vertical Curve When S is Greater Than L

U.S. Customary English Units

See Roadway Design Manual Figure 4-J

This program calculates sight distance on a sag vertical curve when the sight distance is greater than the length of curve. Using the calculated sight distance, find Vcalc in the table below.

S = (400+LA)/(2A-3.5)

Enter L and A
L = Length of Vertical Curve (ft.)
A = Algebraic Difference in Grade
Sight Distance (ft.)


S feet 152 160 169 178 187 197 197 216 226 236 246 257 267 278 289 301
Vcalc mph 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
 
S feet 312 324 335 348 360 372 385 398 411 424 437 451 464 478 492 507
Vcalc mph 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56
 
S feet 521 536 551 566 581 597 612 628 644 661 677 694 711 728
Vcalc mph 57 58 59 60 61 62 63 64 65 66 67 68 69 70


Last updated date: October 9, 2020 11:37 AM