{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

6 - Chapter3-HorizontalCurves

# 6 - Chapter3-HorizontalCurves - Geometric Highway Design...

This preview shows pages 1–16. Sign up to view the full content.

Geometric Highway Design: Horizontal Curves TTE 4004 Lecture 6 9/12/11

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Chapter 3 Outline Vertical Curve Design Vertical curve fundamentals Stopping sight distance Crest vertical curves Sag vertical curves Passing sight distance – crest vertical curves Underpass sight distance – sag vertical curves Horizontal Curve Design Vehicle cornering Horizontal curve fundamentals Stopping sight distance – horizontal curves Combination of horizontal and vertical curves
Recap: Vertical Curves PVC: Point of Vertical Curvature PVI: Point of Vertical Intersection (of initial and final tangents) PVT: Point of Vertical Tangency

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Recap: Vertical Curves Parabolic curves are generally used for design Parabolic function y = ax 2 + bx + c 1 G dx dy b = = ( 29 L G G a 2 1 2 - =
Recap: Vertical Curve Offsets 2 200 x L A Y = 800 AL Y m = 200 AL Y f =

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Recap: Crest Vertical Curve US Customary Metric For SSD < L 2158 SSD 2 × = A L m 658 SSD 2 × = A L m (3.15) For SSD > L A L m 2158 SSD 2 - × = A L m 658 SSD 2 - × = (3.16)
Recap: Sag Vertical Curve US Customary Metric For SSD < L SSD 5 3 400 SSD 2 × × = . + A L m SSD 5 3 120 SSD 2 × × = . + A L m (3.21) For SSD > L A . + L m SSD 5 3 400 SSD 2 × - × = A . + L m SSD 5 3 120 SSD 2 × - × = (3.22)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Recap: Passing Sight Distance Important for crest vertical curves on two- lane roads
Recap: Underpass Sight Distance + - = 2 800 2 1 2 H H H AS L c m Eq. 3.27 S < L A H H H S L c m + - - = 2 800 2 2 1 Eq. 3.28 S > L

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Sag Curve Example A 1600-ft-long sag vertical curve (equal tangent) as a PVC at station 120+00 and elevation 1500 ft. The initial grade is -3.5% and the final grade is 6.5%. Determine the elevation and stationing of the low point, PVI, and PVT.
PVI Station Elevation

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
PVT Station Elevation Elevation
PVT (Continued) Elevation

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Low Point - Station
Low Point - Elevation

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}