Street Design Manual

Table 13 Horizontal and Vertical Alignment Design Criteria

Min. Vertical Curve Length ** (feet)

Min. centerline Radius (feet)

Max. Rate of Superelevation for Min. CL Radius (ft per ft)

Design Speed (mph)

Min. tangent b/w reverse curves (feet)

Maximum Gradient * (%)

Minimum rate of vertical curvature, K (LF per % of A ***) Crest Sag

New Street Classifications

Sensitive Area Streets 1. Sensitive Area Parkway 2. Sensitive Area Avenue

50 40 35 25 25 25 35 25 30 35 40 30 30 40 40 50 40 40 35 20 20

930 535 375 150 150 150 375 150 250 375 535 250 250 535 535 930 535 535

0.04 0.04 0.04

400 250 200

7 8 9

150 125 100

84 44 29 12 12 12 30 12 19 30 44 19 19 44 44 84 44 44 29 12 12

96 64 49 26 26 26 50 26 37 50 64 37 37 64 64 96 64 64 49 26 26

3. Sensitive Area Residential Street Collector 4. Sensitive Area Residential Street Local

NA

0

12

50

Local Street 1. Neighborhood Yield 2. Neighborhood Local

NA NA

0 0

12 12

50 50

3. Neighborhood Street (Collector)

0.04

200

9

100

4. Multifamily Street Mixed Use Streets 1. Avenue 2

NA

0

12

50

‐ Lane Undivided ‐ Lane Divided ‐ Lane Parallel Parking ‐ Lane, Parallel Parking ‐ Lane, Divided ‐ Lane Divided ‐ Way Boulevard, Parallel Parking ‐ Way Boulevard, Angular Parking

0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04

150 200 250 150 150 250 250 400 250 250

9 8 8 9 9 8 8 7 8 8

100 100 125 100 100 125 125 150 125 125

2. Avenue 2 3. Avenue 3

4. Main Street Parallel Parking 5. Main Street Angular Parking

Major Streets 1. Avenue 4 2. Avenue 4 3. Avenue 6

4. Multi 5. Multi

Industrial and Service Streets 1. Industrial Street

375

0.04

200

9

100

2. Alley, Residential 3. Alley, Mixed Use

75 75

NA NA

0 0

12 12

50 50

Accessways 1. Primary Internal Access Drive

25

150

NA

0

12

50

12

26

Note: * The minimum gradient on streets shall be at least 0.75%. ** All vertical curves must be symmetrical parabolic curves. *** A=the algebraic difference in vertical curve grades

Raleigh Street Design Manual – Page 85