Horizontal Alignment

Horizontal Alignment - Geometric Design of Highways...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Geometric Design of Highways Horizontal Alignment: Vehicle Cornering Fundamentals: d F’ = (W/g)(v 2 /R) cos B C.G. W sin F=ma n =(W/g)(v 2 /R) (W/g)(v 2 /R) sin H E f s N A W N=W cos W = in lb F = in lb R = in ft F s = coefficient of side friction v = in ft/s F = ma n = (W/g)(v 2 /R) = centripetal or centrifugal force Superelevation F x 0 w g v R W fN 2 cos sin where N=N 1 + N 2 W f W f w g v R s s sin ( cos ) sin 2 divide by W cos v gR f f v gR s s 2 2 tan tan tan = e superelevation f v gR s 2 tan set this equal to zero because of small f s and small tan (a conservative assumption)
Background image of page 1

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

View Full DocumentRight Arrow Icon
2 tan = e h = 1 ft x = 100 ft e =0.01 Solve for R, R v g f e v s 2 ( ) g = 32.2 ft/s 2 v = ft/s R v = ft (vehicle’s traveled path) ) e f ( 15 v R ) e f ( 2 . 32 ) v 47 . 1 ( R s 2 s 2 v = mph R = ft Overturning Speed M B 0 0 ) H sin W ( 2 d cos W 2 d sin R v g W H cos R v g W 2 2 divide by W cos v gR H v gR d d H 2 2 2 2 0 tan (tan ) divide by H and substitute for tan = e v gR v gR e d H d H e 2 2 2 2 0 ( ) 0 e
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/09/2011 for the course ECON 2250 taught by Professor Schultz during the Spring '11 term at UNO.

Page1 / 7

Horizontal Alignment - Geometric Design of Highways...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online