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36 CHAPTER FOUR PAVEMENT MARKINGS AT INTERCHANGES Figures 3B-8 and 3B-9 (see Appendix A) show examples of specifically prohibit the use of chevrons in the paved gores the pavement markings that are used in the gore areas of for entrance ramps. entrance and exit ramps, including channelizing lines and optional chevron markings. Figure 10 shows an example of Figure 3B-9 provides examples of entrance ramps with the use of diagonal lines within the paved gore of an exit ramp. parallel and tapered acceleration lanes. Chevrons are not shown in the paved gores. Wide channelizing lines that begin at the upstream end of the paved gore are shown on both 2003 MUTCD Provisions sides of the paved gore for the parallel acceleration lane example. In the example with the tapered acceleration lane, Paragraph 1 of Section 3B.05 contains the following stan- a wide channelizing line that begins at the upstream end of dard: "A channelizing line shall be a wide or double solid white the paved gore is shown only on the ramp side of the paved line." A wide line is 8 to 12 in. wide. A double line consists gore. The wide channelizing line ends before the down- of two parallel lines separated by a discernible space. stream end of the gore and a broken lane line is used to define the remainder of the ramp side of the paved gore. Paragraph 6 of Section 3B.05 contains the following sup- port: "Channelizing lines at entrance ramps as shown in Fig- ure 3B-9 promote reasonably safe and efficient merging with Figure 3B-8 provides examples of exit ramps with paral- the through traffic." lel and tapered deceleration lanes. Chevrons are shown in the paved gores, but a note indicates that they are optional. The Paragraph 9 of Section 3B.05 contains the following guid- note for Drawing "c" indicates that the markings within the ance: "For entrance ramps, a channelizing line should be placed paved gore may also be diagonal lines rather than chevrons. along the side of the neutral area adjacent to the ramp lane." Wide channelizing lines that end at the downstream end of the paved gore are shown on both sides of the paved gores. Paragraph 11 of Section 3B.05 contains the following In the example with the tapered deceleration lane, an optional option: "For entrance ramps with a tapered acceleration lane, dotted extension of the right edge line is shown upstream lane line markings may be placed to extend the channelizing from the upstream end of the paved gore. Figure 3B-10 pro- line, but not beyond a point where the tapered lane meets the vides an example of an exit ramp where chevrons are not near side of the through traffic lane as shown in Figure 3B-9." shown in the paved gore (see Appendix A for figures). Paragraph 5 of Section 3B.05 contains the following sup- ENTRANCE RAMP GORES port: "Channelizing lines at exit ramps as shown in Figure 3B-8 define the neutral area, direct exiting traffic at the Width of Channelizing Lines (43 agencies) proper angle for smooth divergence from the main lanes into the ramp, and reduce the probability of colliding with objects The following widths are explicitly specified in the design adjacent to the roadway." standards for the channelizing lines associated with entrance ramps: Paragraph 7 of Section 3B.05 contains the following stan- dard: "For exit ramps, channelizing lines shall be placed along UT--4 in. for parallel acceleration lanes and 8 in. for the sides of the neutral area adjacent to the through traffic lane tapered acceleration lanes and the ramp lane." This standard is universally followed. WV--6 to 8 in. CA, CO, CT, FL, HI, IL, IN, IA, KS, LA, MA, MN, MO, Paragraph 8 of Section 3B.05 contains the following MT, ND, OK, OR, PA, TN, TX, VA, WA, WI, WY, option: "White chevron markings may be placed in the neu- PR, NYC--8 in. tral area for special emphasis as shown in Figure 3B-8." AL, NC, OH--8 in. or 12 in. Although this paragraph immediately follows a paragraph SC--8 in. for primary and secondary highways and 12 in. regarding exit ramps and although Figure 3B-9 does not for expressways and freeways mention the option of using chevrons in the paved gores for GA, MD--10 in. entrance ramps, there are no provisions in the MUTCD that AZ, DE, MI, MS, NE, NH, NY, RI, VT--12 in.

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37 FIGURE 10 Examples of use of diagonal lines in paved gores (Source: West Virginia DOT 1994 Standard Details Book, Sheet TEM-1). Upstream End of Channelizing Line on Left-Hand AZ, DE, IL, MD, PA, TN, WI--50 ft Side of Entrance Ramp (42 agencies) NC--where the paved shoulders portion of the gore starts OK--downstream end of the paved shoulder on the ramp The following points (measured upstream from the upstream NE, SC, NYC--unspecified distance upstream. end of the paved gore) are explicitly specified in the design standards for the upstream end of the channelizing line on the left-hand side of the entrance ramp: Downstream End of Channelizing Line on Left-Hand Side of Entrance Ramp (26 agencies) AL, CA, FL, GA, IN, IA, KS, LA, MA, MI, MN, MS, The design standards consistently show the channelizing line MO, MT, NY, ND, OH, OR, TX, UT, VT, VA, WA, on the left-hand side of an entrance ramp extending to the WY, PR--0 ft downstream end of the paved gore (where the ramp and the CO--just upstream mainline roadway become adjacent to one another) when a NH--5 ft parallel acceleration lane is used. CT--20 ft WV--25 ft The following points are explicitly specified in the design HI--40 ft standards for the downstream end of the channelizing line

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38 on the left-hand side of an entrance ramp when a tapered OR, PA, TN, TX, VT, VA, PR, and NYC) show that the use acceleration lane is used: of a channelizing line on the right-hand side of the mainline roadway is required. NC--upstream end of the paved gore ND--195 ft downstream from the upstream end of the The design standards for seven agencies (CA, CO, CT, paved gore OH, SC, UT, and WA) state that channelizing lines are not WV--midpoint of the paved gore used on the right-hand side of the mainline roadway. WY--point where ramp and mainline roadway are the same distance apart as the width of the mainline shoulder The design standards for nine agencies (GA, IL, IA, MN, CA, CO, GA, HI, IL, MN, MT, NY, OH, TN, WA--point NY, ND, WV, WI, and WY) state that channelizing lines are where ramp and mainline roadway are 6 ft apart not used on the right-hand side of the mainline roadway AZ, NH--point where ramp and mainline roadway are when a tapered acceleration lane is used, but are used on the 5 ft apart right-hand side of the mainline roadway when a parallel UT--point where ramp and mainline roadway are 3 ft apart acceleration lane is used. IA--point where ramp and left edge line of a 2-lane main- line roadway are 28 ft apart Upstream End of Channelizing Line on Right-Hand IN, OK, PA, VT, WI, PR--downstream end of the paved Side of Mainline Roadway (34 agencies) gore. The following points (measured upstream from the upstream end of the paved gore) are explicitly specified in the design Extension of Channelizing Line on Left-Hand Side standards for the upstream end of the channelizing line on the of Entrance Ramp (26 agencies) right-hand side of the mainline roadway: The design standards consistently show the channelizing line AL, FL, GA, IL, IN, IA, KS, LA, MA, MI, MN, MS, MO, extension on the left-hand side of an entrance ramp extending MT, NY, ND, OK, OR, TX, VT, VA, WY, PR--0 ft to the downstream end of the paved gore (where the left-hand NH--5 ft side of the ramp reaches the edge of the mainline roadway) WV--25 ft when a tapered acceleration lane is used. HI--40 ft DE--less than 50 ft (the point on the right edge line where The following widths are used for the channelizing line a perpendicular line would line up with the upstream extensions on the left-hand side of entrance ramps when a end of the gore striping on the ramp) tapered acceleration lane is used: AZ, MD, PA, TN--50 ft NC--where the paved shoulders portion of the gore starts CA, CO, IA, MT, NC, ND, WY--4 in. NE, NYC--unspecified distance prior. GA--5 in. AZ, NH--6 in. Use Versus Non-Use of Chevrons The following patterns are used for the channelizing line Within Paved Gore (44 agencies) extensions on the left-hand side of entrance ramps when a The design standards for four agencies (FL, OK, TN, and PR) tapered acceleration lane is used: show that the use of chevrons within the paved gores of CA--7-ft segments with 17-ft gaps entrance ramps is required. The design standards for Ten- AZ, CO, GA, HI, IL, IA, MT, NH, NC, ND, OH, TN, UT, nessee note that if the gore area is so short that at least five chevrons cannot be placed within the gore, the chevrons are WV, WY--10-ft segments with 30-ft gaps. omitted from the gore area. The design standards for New York show a partial barrier The design standards for three agencies (KY, MD, and line (a 6-in.-wide solid line on the gore side and a 6-in.-wide VA) show that the use of chevrons within the paved gores of broken line with 10-ft segments and 30-ft gaps on the ramp entrance ramps is optional. side) being used to extend the channelizing line on the left- hand side of the entrance ramp. The design standards for 36 agencies (AL, AZ, CA, CO, CT, DE, GA, HI, IL, IA, KS, LA, MA, MI, MN, MS, MO, MT, NE, Use Versus Non-Use of Channelizing Line NH, NY, NC, ND, OH, OR, PA, RI, SC, TX, UT, VT, WA, on Right-Hand Side of Mainline Roadway WV, WI, WY, and NYC) state or show that chevrons are not (42 agencies) used within the paved gores of entrance ramps. The design standards for 26 agencies (AL, AZ, DE, FL, HI, The design standards for Indiana state that chevrons are not IN, KS, LA, MD, MA, MI, MS, MO, MT, NE, NH, NC, OK, used within the paved gores of entrance ramps when a parallel