§ 155.046 RESIDENTIAL COLLECTOR ROADS.

   (A)   Dead end roads: more than 2,500 feet in length;

   (B)   Connecting roads between the local residential subdivision roads and the thoroughfare system;

   (C)   Loop roads: more than one mile in length; and

   (D)   Other roads having a "collector" type function in the thoroughfare system.

Terrain Classification	Level (Cross Slope Range of 0% to 8%)	Rolling (Cross Slope Range of 8.1% to 15%)	Hilly (Cross Slope over 15%)
Right-of-Way Width
Curb and gutter section	50'	50'	50'
Shoulder section	50'	50'	50'
Pavement Width
Curb and gutter section	34' G-G	34' G-G	34' G-G
Shoulder section	20'	20'	20'
G-G refers to face to face of standard curb and gutter section, bottom of the "V to the bottom of the "V" for the valley types section. Other types will be reviewed by the Division Engineer with the G-G limits applicable
Minimum Shoulder Width
Shoulder section	6'	6'	6'
Maximum Cut and Fill Slopes	2:1	2:1	2:1
Design Speed	35 mph	30 mph	25 mph
Minimum Sight Distance on Vertical Curves	250'	200'	150'
Minimum Centerline Radius	310'	230'	150'
Minimum Superelevation Rate
Minimum radius	.08 ft/ft	.06 ft/ft	.04 ft/ft
Maximum Grade, Grades for 100' each way from intersection exceeding 5% may be reviewed by District Engineers for consideration. Grades less than 0.5% should not be used unless reviewed individually by the District Engineer to determine potential maintenance problems	6%	9%	12%
K = Rate of Vertical Curvature for minimum sight distance
CREST	45	30	20
SAG	30	20
STOP	20	14	9
Formula for determination of length of vertical curve required to provide minimum sight distance.
[L = KA]
L = Length of vertical curve in feet
K = Rate of vertical curvature in feet per percent of A
A = Algebraic difference in grades in percent
NOTES TO TABLE:
* - On cul-de-sacs, a maximum of two-tenths of a mile in length, 18 feet of pavement will be allowed (not including gutter). (See §§ 155.061, 155.066 and 155.069.) Cul-de-sac designs other than the "bulb" end design will be subject to the approval of th Division Engineer after review on an individual basis. See § 155.068 for several examples of minor residential cul-de-sac designs.
** - The minimum superelevation rates shown for the varying design speeds are for the minimum radii shown. For radii different from these, use the appropriate table from the 1994 Edition of AASHTO's Policy on Geometric Design of Highways and Streets for a desirable design. For a minimum design, the superelevation rate can be calculated from the simplified curve formula:
e = (v2) -f (15R)
where
e = superelevation rate in foot per foot
V = design speed in miles per hour
R = radius of curve in feet
f = side friction factor (See page 143 of the 1994 Policy on Geometric Design of Highways and Streets)
Short cul-de-sacs and dead end streets 1500 feet or less in length may be accepted without superelevation.

 

(Ord. passed 1-1-2000)