1 / 14

Intersection Sight Distance Case C1 Ryan Miller CE 480 10/19/10

Intersection Sight Distance Case C1 Ryan Miller CE 480 10/19/10. Objective. Introduction Approach sight triangles Departure sight triangles Special situations. Introduction. Intersections with yield control on minor road Considers crossing maneuver from minor road

dane
Télécharger la présentation

Intersection Sight Distance Case C1 Ryan Miller CE 480 10/19/10

An Image/Link below is provided (as is) to download presentation 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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Intersection Sight DistanceCase C1Ryan MillerCE 48010/19/10

  2. Objective • Introduction • Approach sight triangles • Departure sight triangles • Special situations

  3. Introduction • Intersections with yield control on minor road • Considers crossing maneuver from minor road • Must consider both approach and departure sight triangles • Sight distances needed by drivers exceed those for stop-controlled approaches

  4. Introduction • Minor road vehicle can cross major road without stopping if no potentially conflicting vehicles on major road • Minor road vehicle assumed to decelerate at rate of 1.5 m/s2while traveling from decision point to intersection • Minorroad vehicle assumed to cross and clear intersection at 60% of design speed

  5. Approach Sight Triangles • Distance along minor street to major street (a) • Distance along major street to vehicle with right-of-way (b) • Must check both left and right directions • Use Exhibit 9-60 to find (a) • Use equations 9-2 to find (b)

  6. Approach Sight Triangles

  7. Approach Sight Triangles

  8. Approach Sight Triangles

  9. Approach Sight Triangles Vmajor= 45 mph Both approach grades= 0% Vminor= 25 mph Lw= 12 ft La=19 ft (PC)

  10. Approach Sight Triangles

  11. Approach Sight Triangles a= 130 fta=142 ft ta= 4.0 s tg= 6.5 s b=b= 1.47Vmajortg= 1.47x45x6.5= 430 ft

  12. Approach Sight Triangles

  13. Departure Sight Triangles • Departure sight triangles automatically considered • tg must meet minimum value from exhibit 9-57 (used for B3 intersection)

  14. Special Cases • Major road is divided highway with narrow median • Consider additional crossing width • Major road is divided highway with wide median • Crossing maneuver need only consider crossing near lanes • Crossing far lanes must be accomplished from stopped position (departure triangle)

More Related