Engineering and Aesthetics

1 / 21

# Engineering and Aesthetics - PowerPoint PPT Presentation

Session 3. Engineering and Aesthetics. Engineering vs. Aesthetics. Source: City of Bellevue, “Speed Hump: Design, Pavement Marking, and Signing” . Design of Horizontal Measures. R = V 2 /15(e+f) R = radius of a horizontal measure (ft) V = speed of travel through the measure (mph)

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about 'Engineering and Aesthetics' - mallorie

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Session 3

Engineering and Aesthetics

Engineering vs. Aesthetics

Source: City of Bellevue, “Speed Hump: Design, Pavement Marking, and Signing”

Design of Horizontal Measures
• R = V2/15(e+f)
• R = radius of a horizontal measure (ft)
• V = speed of travel through the measure (mph)
• e = superelevation rate of road
• f = side friction factor

Design, Operating, & Posted Speeds

Critical Point Design Speed

Mean Operating Speed

Posted Speed Limit

AASHTO Design Speed

Tangent

Curve

Tangent

Curve

Tangent

ALIGNMENT

Maximum Curve Radii for Various Desired Speeds

Desired

Speed

Assumed

Side Friction1

Assumed

Superelevation

Maximum

• 15 mph

0.38

0.00

43

0.00

88

• 20

0.30

• 25

0.25

0.00

167

• 30

0.22

0.00

273

1Based on American Association of State Highway and Transportation Officials (AASHTO), A Policy on Geometric Design of Highways and Streets, Washington, D.C., 1990, Figure III-17 and Table III-17.

Another Constraint -- Long Wheelbase Vehicles

Source: KPG, Inc., Design Report for SE 46th Way Traffic Control Improvements, City of Bellevue, WA, 1994.

Design of Vertical Measures
• A = 2.15V2/R R = V2/5.81
• A = acceleration (ft/sec2)V = speed of travel over a vertical measure (mph)R = radius of the measure (ft)
Landscaping Policies

Agency Neighborhood

Dayton, OH install maintain

Eugene, OR install maintain till volunteer dies/moves

Gainesville, FL install maintain

choose plants from city nursery

Howard Co., MD install &

maintain

Montgomery Co. install maintain

choose landscape palette

San Diego, CA install maintain

choose plants from approved list

Tallahassee, FL install & maintain

reconsidering because of “uglies”

MUTCD General Guidance
• ... engineering judgment is essential to the proper use of signs, the same as with other traffic control devices
• Information of a less important nature and extraneous information should be moved to less critical locations or deleted
• A conservative use of regulatory and warning signs is recommended as these signs, if used to excess, tend to lose their effectiveness
• In situations where messages are required other than those herein provided for, the signs shall be the same shape and color as standard signs of the same functional type
MUTCD Operational Guidance
• Yellow diamond-shaped signs for warning
• Yellow lines separating opposing traffic
• Lettering or symbols of adequate size
• Short legends
• Symbols in preference to word messages
• Educational plaques with new specialty signs
• Advance warning when high driver judgment or deceleration to a specific speed is required
• Size, height, position, lettering, and reflectorization per MUTCD