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PAVEMENT AND CURB MARKINGS Done by: Abdullah Eawada Mohammed Habboub Presented to: Dr. Esam Almasri. Why Using Pavement Markings?. “ Pavement markings can enhance safety since centerlines have been shown to cut crash frequency by 29% compared to roads without them ”.
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PAVEMENT AND CURB MARKINGS Done by: Abdullah EawadaMohammed Habboub Presented to: Dr. EsamAlmasri
“Pavement markings can enhance safety since centerlines have been shown to cut crash frequency by 29% compared to roads without them” Wisconsin Transportation Bulletin • No. 9
Limitations: Obliterated by snow Not clearly visible when wet Not very durable under heavy traffic Need refreshment every year or more Advantages: conveying information to drivers without diverting their attention from the road. Inexpensive
Markings that must be visible at night shall be retroreflective • In any case, all markings on Interstate highways shall be retroreflective. • Markings must be clear
Red: • Raised pavement markings
Markings Categories: • Longitudinal • Transverse
Longitudinal Lines: • Yellow • White
Yellow Lines: • Center Line • No-Passing Zone • Other
Yellow Center Line Pavement Markings Warrants • It used to delineate the separation of traffic lanes that have opposite directions of travel on a roadway
Yellow center Line could be: • A normal broken yellow line … crossing the center line markings is permitted. • A broken line is formed of segments and gaps, usually in the ratio of 1:3.
Yellow center Line could be: • One-direction no-passing zone … crossing the center line markings for passing with care is permitted for the traffic traveling adjacent to the broken line, but is prohibited for traffic traveling adjacent to the solid
Yellow center Line could be: • Two-direction no-passing zone… crossing the center line markings for passing is prohibited for traffic traveling in either directions.
Yellow center Line should be placed in: • Urban arterials and collectors that is: • 20 feet or more in width and • ADT of 6,000 vehicles per day or greater. • All rural arterials and collectors that is: • 18 feet or more in width and • ADT of 3,000 vehicles per day or greater. • All two-way streets or highways that have three or more lanes.
Other Yellow Line Type: • If reversible lanes :consist of a normal broken double yellow line to delineate the edge of a lane in which the direction of travel is reversed from time to time.
White normal broken line • Used on all roadways that are intended to operate with two or more adjacent traffic lanes in the same direction of travel
White dotted line • Used to separate a through lane that is : • A deceleration or acceleration lane. • A through lane that becomes a mandatory exit or turn lane. • They have noticeably shorter segments: for example, a 2’ line and a 2’ to 6’ gap.
Dotted Deceleration • Parallel • Tapered
Dotted deceleration • Parallel with multilane
Dotted Acceleration • Parallel • Tapered
Dotted Acceleration • Tapered
Wide dotted white lane line • It is used: • As a lane drop marking in advance of lane drops at exit ramps to distinguish a lane drop from a normal exit ramp.
Wide dotted white lane line • It is used: • In advance of freeway route splits with dedicated lanes
Wide dotted white lane line • It is used: • To separate a through lane that continues beyond an interchange from an adjacent. • Or An Auxiliary lane between an entrance ramp and an exit ramp
Wide dotted white lane line • It is used: • As a lane drop marking in advance of lane drops at intersections to distinguish a lane drop from an intersection through lane
Wide dotted white lane line • It is used: • To separate a through lane that continues beyond an intersection from an adjacent auxiliary lane between two intersections
Through Intersections Markings • White • Yellow
Wide dotted white lane line • It may be used: • Through intersections. Where greater restriction is required, solid lane lines or channelizing lines should be extended into or continued through intersections or major driveways.
Lane-Reduction Transition Markings • White • Yellow
Lane-Reduction Transition Markings • Used to guide traffic through transition areas where the number of through lanes is reduced
Approach Markings for Obstructions • White • Yellow