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Publication Number: FHWA-HRT-13-047
Date: August 2013

 

Simulator Study of Signs for A Complex Interchange and Complex Interchange Spreadsheet Tool

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APPENDIX C. DESCRIPTION OF SURVEY SITES USED IN DEVELOPING THE SPREADSHEET TOOL

This appendix contains descriptions of each of the 28 interchanges used in developing the complex interchange spreadsheet tool. The descriptions each contain an aerial photograph, a brief description of the interchange's location and routes, and a summary of the characteristics used in the spreadsheet.

Information for site AZ-1 is as follows:

Figure 80. Photo. Aerial view of site AZ-1. This figure shows an aerial photo of the interchange of I-10 with I-17/US-60 in Phoenix, AZ. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 80. Photo. Aerial view of site AZ-1. (50)

Table 49. Characteristics of AZ-1.
Variable NB SB EB WB
Study length (ft) 9,010 9,590 13,755 12,665
Number of concurrent routes 2 2 1 1
Number of levels 4 4 4 4
Number of missing movements 0 0 0 0
Number of ramps 4 4 5 4
Exit ramps per mile 1.17 1.10 1.15 0.83
Entrance ramps per mile 1.17 1.10 0.77 0.83
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.59 0.55 0.00 0.42
Multilane exit ramps per mile 0.59 0.55 0.38 0.42
Optional/shared exit lanes per mile 0.59 1.10 0.77 0.42
Exit only lanes per mile 1.17 1.10 0.77 0.83
Score 355 505 490 470
Overall score 455

Information for site AZ-2 is as follows:

Figure 81. Photo. Aerial view of site AZ-2. This figure shows an aerial photo of the interchange of I-10 with SR 51 and LP 202 in Phoenix, AZ. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 81. Photo. Aerial view of site AZ-2. (51)

Table 50. Characteristics of AZ-2.
Variable NB SB EB WB
Study length (ft) 9,450 10,555 5,555 10,455
Number of concurrent routes 1 1.125 1 1
Number of levels 4 4 4 4
Number of missing movements 0 0 0 0
Number of ramps 4 8 2 7
Exit ramps per mile 1.68 1.50 1.90 1.52
Entrance ramps per mile 0.56 2.00 0.00 2.02
Left exits per mile 0.56 0.50 0.95 0.51
Left entrances per mile 0.00 1.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.95 1.01
Multilane exit ramps per mile 0.56 0.50 0.95 0.00
Optional/shared exit lanes per mile 1.68 0.50 1.90 0.00
Exit only lanes per mile 0.56 1.50 1.90 1.52
Score 440 605 370 620
Overall score 508.75

Information for site AZ-3 is as follows:

Figure 82. Photo. Aerial view of site AZ-3. This figure shows an aerial photo of the interchange of I-17 with SR 69 in Prescott, AZ. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 82. Photo. Aerial view of site AZ-3. (52)

Table 51. Characteristics of AZ-3.
Variable NB SB EB WB
Study length (ft) 46,355 46,360 6,945 4,305
Number of concurrent routes 1 1 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 2 4 2 2
Exit ramps per mile 0.11 0.23 0.76 1.23
Entrance ramps per mile 0.11 0.23 0.76 1.23
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.11 0.00 0.00 0.00
Multilane exit ramps per mile 0.00 0.00 0.00 0.00
Optional/shared exit lanes per mile 0.11 0.11 0.00 1.23
Exit only lanes per mile 0.00 0.11 0.76 0.00
Score 154 230 270 300
Overall score 236.25

Information for site DE-1 is as follows:

Figure 83. Photo. Aerial view of site DE-1. This figure shows an aerial photo of the interchange of I-95 with SR 1/SR 7 and Churchmans Road in Wilmington, DE. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 83. Photo. Aerial view of site DE-1. (53)

Table 52. Characteristics of DE-1.
Variable NB SB EB WB
Study length (ft) 6,300 6,642 16,405 19,255
Number of concurrent routes 2 2 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 5 3 4 3
Exit ramps per mile 2.51 0.79 0.64 0.55
Entrance ramps per mile 1.68 1.59 0.64 0.27
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.79 0.00 0.27
Multilane exit ramps per mile 0.00 0.79 0.00 0.00
Optional/shared exit lanes per mile 0.84 0.79 0.00 0.00
Exit only lanes per mile 1.68 0.79 0.64 0.55
Score 375 325 170 170
Overall score 260

Information for site DE-2 is as follows:

Figure 84. Photo. Aerial view of site DE-2. This figure shows an aerial photo of the interchange of I-95/I-295 with US-202/SR 141 in Wilmington, DE. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 84. Photo. Aerial view of site DE-2. (54)

 

Table 53. Characteristics of DE-2.
Variable NB SB EB WB
Study length (ft) 4,855 3,625 10,320 17,405
Number of concurrent routes 2 2 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 1 0
Number of ramps 5 4 2 3
Exit ramps per mile 2.18 4.37 0.51 0.30
Entrance ramps per mile 3.26 1.46 0.51 0.61
Left exits per mile 1.09 1.46 0.00 0.00
Left entrances per mile 0.00 0.00 0.51 0.30
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.51 0.30
Multilane exit ramps per mile 0.00 0.00 0.51 0.30
Optional/shared exit lanes per mile 1.09 2.91 0.51 0.00
Exit only lanes per mile 1.09 1.46 0.51 0.61
Score 465 435 335 420
Overall score 413.75

Information for site DE-3 is as follows:

Figure 85. Photo. Aerial view of site DE-3. This figure shows an aerial photo of the interchange of I-295 with SR 13/US-40 in Wilmington, DE. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 85. Photo. Aerial view of site DE-3. (55)

Table 54. Characteristics of DE-3.
Variable NB SB EB WB
Study length (ft) 3,085 1,990 10,010 9,180
Number of concurrent routes 2 2 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 5 4 4 3
Exit ramps per mile 1.71 5.31 1.05 0.58
Entrance ramps per mile 6.85 5.31 1.05 1.15
Left exits per mile 1.71 2.65 0.00 0.00
Left entrances per mile 5.13 2.65 0.53 0.58
Number of exit ramps with multiple destinations per mile 0.00 2.65 0.00 0.58
Multilane exit ramps per mile 1.71 0.00 0.00 0.58
Optional/shared exit lanes per mile 1.71 0.00 0.00 0.00
Exit only lanes per mile 1.71 5.31 1.05 1.15
Score 465 465 360 390
Overall score 420

Information for site GA-2 is as follows:

Figure 86. Photo. Aerial view of site GA-2. This figure shows an aerial photo of the interchange of I-85/SR 403 with I-285 in Atlanta, GA. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 86. Photo. Aerial view of site GA-2. (56)

Table 55. Characteristics of GA-2.
Variable NB SB EB WB
Study length (ft) 12,215 12,090 11,530 9,065
Number of concurrent routes 2 2 1 1
Number of levels 3 3 3 3
Number of missing movements 0 0 0 0
Number of ramps 4 4 4 3
Exit ramps per mile 0.86 0.87 0.92 0.58
Entrance ramps per mile 0.86 0.87 0.92 1.16
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.43 0.44 0.46 0.00
Multilane exit ramps per mile 0.43 0.87 0.92 0.00
Optional/shared exit lanes per mile 0.43 0.87 0.46 0.00
Exit only lanes per mile 0.86 0.87 1.37 0.58
Score 415 415 350 300
Overall score 370

Information for site GA-3 is as follows:

Figure 87. Photo. Aerial view of site GA-3. This figure shows an aerial photo of the interchange of I-85/SR 403 with SR 316 in Atlanta, GA. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 87. Photo. Aerial view of site GA-3.(57)

Table 56. Characteristics of GA-3.
Variable NB SB EB WB
Study length (ft) 17,450 16,095 8,285 13,920
Number of concurrent routes 2 2 1 1
Number of levels 2 2 2 2
Number of missing movements 0 1 0 0
Number of ramps 4 4 2 4
Exit ramps per mile 0.91 0.33 0.00 1.52
Entrance ramps per mile 0.30 0.98 1.27 0.00
Left exits per mile 0.30 0.00 0.00 0.76
Left entrances per mile 0.00 0.33 0.64 0.00
Number of exit ramps with multiple destinations per mile 0.30 0.00 0.00 0.00
Multilane exit ramps per mile 0.61 0.00 0.00 0.00
Optional/shared exit lanes per mile 0.61 0.00 0.00 0.76
Exit only lanes per mile 0.91 0.33 0.00 0.76
Score 435 250 200 380
Overall score 316.25

Information for site GA-4 is as follows:

Figure 88. Photo. Aerial view of site GA-4. This figure shows an aerial photo of the interchange of I-75/SR 401 with I-16/SR 404 in Macon, GA. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 88. Photo. Aerial view of site GA-4. (58)

Table 57. Characteristics of GA-4.
Variable NB SB EB WB
Study length (ft) 5,810 12,025 2,400 8,680
Number of concurrent routes 2 2 2 2
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 1 2 1 1
Exit ramps per mile 0.91 0.44 0.00 0.00
Entrance ramps per mile 0.00 0.44 2.20 0.61
Left exits per mile 0.00 0.44 0.00 0.00
Left entrances per mile 0.00 0.44 2.20 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.00 0.00
Multilane exit ramps per mile 0.91 0.00 0.00 0.00
Optional/shared exit lanes per mile 0.00 0.00 0.00 0.00
Exit only lanes per mile 1.82 0.44 0.00 0.00
Score 295 265 225 105
Overall score 222.5

Information for site IN-1 is as follows:

Figure 89. Photo. Aerial view of site IN-1. This figure shows an aerial photo of the interchange of I-80/I-94/US-6 with I-65 in Gary, IN. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 89. Photo. Aerial view of site IN-1.(59)

Table 58. Characteristics of IN-1.
Variable NB SB EB WB
Study length (ft) 16,330 15,650 24,575 10,605
Number of concurrent routes 1 1 3 3
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 4 4 3 4
Exit ramps per mile 0.65 0.67 0.43 0.50
Entrance ramps per mile 0.65 0.67 0.21 1.49
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.34 0.43 0.50
Multilane exit ramps per mile 0.32 0.00 0.21 0.50
Optional/shared exit lanes per mile 0.00 0.00 0.21 0.50
Exit only lanes per mile 0.97 0.67 0.43 0.50
Score 330 230 365 250
Overall score 293.75

Information for site IN-3 is as follows:

Figure 90. Photo. Aerial view of site IN-3. This figure shows an aerial photo of the interchange of I-69/SR 37/Binford Boulevard with I-465/US-421/US-31in Indianapolis, IN. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 90. Photo. Aerial view of site IN-3.(60)

Table 59. Characteristics of IN-3.
Variable NB SB EB WB
Study length (ft) 5,105 6,605 18,015 17,915
Number of concurrent routes 3 2.5 3 3
Number of levels 2 2 2 2
Number of missing movements 1 0 0 1
Number of ramps 3 2 3 3
Exit ramps per mile 1.03 0.80 0.59 0.29
Entrance ramps per mile 2.07 0.80 0.29 0.59
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.80 0.00 0.00
Multilane exit ramps per mile 0.00 0.80 0.00 0.29
Optional/shared exit lanes per mile 0.00 0.80 0.00 0.29
Exit only lanes per mile 1.03 1.60 0.59 0.29
Score 325 330 220 235
Overall score 277.5

Information for site IA-1 is as follows:

Figure 91. Photo. Aerial view of site IA-1. This figure shows an aerial photo of the interchange of I-80/I-35 with I-235/I-35 in Des Moines, IA. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 91. Photo. Aerial view of site IA-1.(61)

Table 60. Characteristics of IA-1.
Variable NB SB EB WB
Study length (ft) 15,105 15,775 18,159 17,100
Number of concurrent routes 1.333 1.333 1.25 1.25
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 3 3 4 4
Exit ramps per mile 0.35 0.33 0.58 0.62
Entrance ramps per mile 0.70 0.67 0.58 0.62
Left exits per mile 0.00 0.00 0.29 0.31
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.35 0.33 0.00 0.00
Multilane exit ramps per mile 0.35 0.33 0.00 0.00
Optional/shared exit lanes per mile 0.00 0.00 0.00 0.31
Exit only lanes per mile 0.70 0.67 0.58 0.31
Score 345 305 275 375
Overall score 325

Information for site IA-2 is as follows:

Figure 92. Photo. Aerial view of site IA-2. This figure shows an aerial photo of the interchange of I-380/SR and 27/US-218 with US-30/US-151/US-28 in Cedar Rapids, IA. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 92. Photo. Aerial view of site IA-2. (62)

Table 61. Characteristics of IA-2.
Variable NB SB EB WB
Study length (ft) 17,250 17,030 5,775 5,815
Number of concurrent routes 2 1.667 2 2.5
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 4 3 4 4
Exit ramps per mile 0.61 0.31 1.83 1.82
Entrance ramps per mile 0.61 0.62 1.83 1.82
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.31 0.00 0.00
Multilane exit ramps per mile 0.00 0.31 0.00 0.00
Optional/shared exit lanes per mile 0.31 0.31 0.00 0.00
Exit only lanes per mile 0.31 0.31 1.83 1.82
Score 255 245 295 270
Overall score 266.25

Information for site IA-3 is as follows:

 

Figure 93. Photo. Aerial view of site IA-3. This figure shows an aerial photo of the interchange of I-29 with I-129 and US-75/US-20 in Sioux Falls, IA. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 93. Photo. Aerial view of site IA-3. (63)

Table 62. Characteristics of IA-3.
Variable NB SB EB WB
Study length (ft) 18,055 17,625 14,595 15,290
Number of concurrent routes 1 1 2.333 2.333
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 4 2 2 3
Exit ramps per mile 0.58 0.30 0.72 0.35
Entrance ramps per mile 0.58 0.30 0.36 0.69
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.30 0.00 0.35
Multilane exit ramps per mile 0.00 0.00 0.00 0.35
Optional/shared exit lanes per mile 0.00 0.00 0.72 0.35
Exit only lanes per mile 0.58 0.30 0.00 0.35
Score 210 145 280 280
Overall score 228.75

Information for site MD-1 is as follows:

 

Figure 94. Photo. Aerial view of site MD-1. This figure shows an aerial photo of the interchange of I-95 with I-695 in Baltimore, MD. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 94. Photo. Aerial view of site MD-1. (64)

Table 63. Characteristics of MD-1.
Variable NB SB EB WB
Study length (ft) 13,450 6,520 7,770 7,755
Number of concurrent routes 1 1 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 3 3 2 3
Exit ramps per mile 0.79 1.62 0.68 1.36
Entrance ramps per mile 0.39 0.81 0.68 0.68
Left exits per mile 0.39 0.81 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.68 0.00
Multilane exit ramps per mile 0.00 0.00 0.68 0.00
Optional/shared exit lanes per mile 0.00 0.00 0.68 0.00
Exit only lanes per mile 0.79 1.62 1.36 1.36
Score 260 270 380 310
Overall score 305

Information for site NY-1 is as follows:

Figure 95. Photo. Aerial view of site NY-1. This figure shows an aerial photo of the interchange of I-95 with I-287 in Port Chester, NY. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 95. Photo. Aerial view of site NY-1. (65)

Table 64. Characteristics of NY-1.
Variable NB SB EB WB
Study length (ft) 15,700 15,730 14,165 9,500
Number of concurrent routes 1 1 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 4 2 3 5
Exit ramps per mile 1.01 0.34 0.75 1.11
Entrance ramps per mile 0.34 0.34 0.37 1.67
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.34 0.00 0.00
Multilane exit ramps per mile 0.00 0.00 0.00 0.00
Optional/shared exit lanes per mile 0.00 0.00 0.00 0.56
Exit only lanes per mile 1.01 0.34 0.75 0.56
Score 200 300 280 360
Overall score 285

Information for site NY-3 is as follows:

Figure 96. Photo. Aerial view of site NY-3. This figure shows an aerial photo of the interchange of US-44/SR 55 with US-9 in Poughkeepsie, NY. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 96. Photo. Aerial view of site NY-3. (66)

Table 65. Characteristics of NY-3.
Variable NB SB EB WB
Study length (ft) 3,270 2,820 10,055 10,150
Number of concurrent routes 1 1 2 2
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 6 6 2 2
Exit ramps per mile 3.23 5.62 0.53 0.52
Entrance ramps per mile 4.84 5.62 0.53 0.52
Left exits per mile 3.23 3.74 0.00 0.00
Left entrances per mile 3.23 3.74 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.00 0.00
Multilane exit ramps per mile 0.00 0.00 0.00 0.00
Optional/shared exit lanes per mile 1.61 1.87 0.00 0.00
Exit only lanes per mile 3.23 3.74 0.53 0.52
Score 490 470 235 195
Overall score 347.5

Information for site OH-1 is as follows:

Figure 97. Photo. Aerial view of site OH-1. This figure shows an aerial photo of the interchange of I-90 with I-77 in Cleveland, OH. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 97. Photo. Aerial view of site OH-1. (67)

Table 66. Characteristics of OH-1.
Variable NB SB EB WB
Study length (ft) 7,235 8,505 0 1,785
Number of concurrent routes 1 1 0 1
Number of levels 2 2 0 2
Number of missing movements 0 0 0 1
Number of ramps 5 4 0 3
Exit ramps per mile 2.92 0.62 0 8.87
Entrance ramps per mile 0.73 1.86 0 0.00
Left exits per mile 0.00 0.00 0 2.96
Left entrances per mile 0.00 0.00 0 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0 5.92
Multilane exit ramps per mile 0.00 0.00 0 2.96
Optional/shared exit lanes per mile 0.73 0.62 0 5.92
Exit only lanes per mile 2.19 0.00 0 5.92
Score 480 360 - 465
Overall score 435

- Indicates no score was generated because EB approach was not present.

Information for site OH-2 is as follows:

Figure 98. Photo. Aerial view of site OH-2. This figure shows an aerial photo of the interchange of I-71 with I-670 in Columbus, OH. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 98. Photo. Aerial view of site OH-2. (68)

 

Table 67. Characteristics of OH-2.
Variable NB SB EB WB
Study length (ft) 12,160 10,840 14,815 13,430
Number of concurrent routes 1 1 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 8 9 8 6
Exit ramps per mile 1.30 1.95 1.43 1.18
Entrance ramps per mile 2.17 0.97 1.43 1.18
Left exits per mile 0.43 0.49 0.71 0.39
Left entrances per mile 0.43 0.00 0.36 0.39
Number of exit ramps with multiple destinations per mile 0.00 0.49 0.36 0.39
Multilane exit ramps per mile 0.43 0.49 0.71 0.79
Optional/shared exit lanes per mile 0.87 0.97 0.36 0.79
Exit only lanes per mile 0.87 1.95 1.78 1.18
Score 700 520 680 610
Overall score 627.5

Information for site OH-3 is as follows:

Figure 99. Photo. Aerial view of site OH-3. This figure shows an aerial photo of the interchange of I-71 with I-71/US-52 in Cincinnati, OH. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 99. Photo. Aerial view of site OH-3.(69)

Table 68. Characteristics of OH-3.
Variable NB SB EB WB
Study length (ft) 8,410 7,945 6,485 8,530
Number of concurrent routes 1.5 1.25 1 1.6
Number of levels 3 3 3 3
Number of missing movements 0 1 1 0
Number of ramps 4 4 4 5
Exit ramps per mile 1.88 1.33 1.63 1.24
Entrance ramps per mile 0.63 1.33 1.63 1.86
Left exits per mile 0.00 0.66 0.00 0.62
Left entrances per mile 0.00 1.33 1.63 0.00
Number of exit ramps with multiple destinations per mile 0.63 0.66 0.81 0.62
Multilane exit ramps per mile 0.63 1.33 0.81 0.62
Optional/shared exit lanes per mile 1.26 0.66 0.00 0.00
Exit only lanes per mile 1.26 1.99 2.44 1.86
Score 565 730 625 495
Overall score 603.75

Information for site OR-1 is as follows:

 

Figure 100. Photo. Aerial view of site OR-1. This figure shows an aerial photo of the interchange of I-5 with I-405/US-30/Fremont Bridge in Portland, OR. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 100. Photo. Aerial view of site OR-1. (70)

 

Table 69. Characteristics of OR-1.
Variable NB SB EB WB
Study length (ft) 6,220 6,580 8,340 5,760
Number of concurrent routes 1 1 1.25 1.5
Number of levels 4 4 4 4
Number of missing movements 0 0 0 0
Number of ramps 3 3 4 4
Exit ramps per mile 1.70 0.80 1.90 0.92
Entrance ramps per mile 0.85 1.60 0.63 2.75
Left exits per mile 0.00 0.00 1.27 0.00
Left entrances per mile 0.00 0.00 0.63 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.80 0.63 0.00
Multilane exit ramps per mile 0.85 0.80 0.63 0.92
Optional/shared exit lanes per mile 1.70 0.00 1.27 0.92
Exit only lanes per mile 0.85 1.60 1.27 0.92
Score 380 370 465 415
Overall score 407.5

Information for site OR-2 is as follows:

Figure 101. Photo. Aerial view of site OR-2. This figure shows an aerial photo of the interchange of I-5 and US-30 with I-84/US-30 in Portland, OR. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 101. Photo. Aerial view of site OR-2.(71)

 

Table 70. Characteristics of OR-2.
Variable NB SB EB WB
Study length (ft) 1,275 9,715 0 5,885
Number of concurrent routes 1.333 1.333 0 2
Number of levels 3 3 0 3
Number of missing movements 0 0 0 0
Number of ramps 3 3 0 1
Exit ramps per mile 0.00 1.09 0 0.90
Entrance ramps per mile 4.14 0.54 0 0.00
Left exits per mile 0.00 0.00 0 0.00
Left entrances per mile 0.00 0.00 0 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.54 0 0.00
Multilane exit ramps per mile 4.14 0.00 0 0.90
Optional/shared exit lanes per mile 4.14 0.54 0 0.90
Exit only lanes per mile 4.14 0.54 0 0.90
Score 395 325 - 295
Overall score 338.33

- Indicates no score was generated because the EB approach was not present.

Information for site SC-1 is as follows:

Figure 102. Photo. Aerial view of site SC-1. This figure shows an aerial photo of the interchange of I-26/US-76 with I-126, US-76, and Bush River Road in Columbia, SC. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 102. Photo. Aerial view of site SC-1. (72)

 

Table 71. Characteristics of SC-1.
Variable NB SB EB WB
Study length (ft) 7,355 8,930 10,115 4,750
Number of concurrent routes 2 2 1 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 4 3 1 1
Exit ramps per mile 1.44 1.18 0.52 0.00
Entrance ramps per mile 1.44 0.59 0.00 1.11
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.52 0.00
Multilane exit ramps per mile 0.00 0.59 0.52 0.00
Optional/shared exit lanes per mile 0.00 0.59 0.00 0.00
Exit only lanes per mile 1.44 1.18 1.04 0.00
Score 345 315 240 50
Overall score 237.5

Information for site SC-2 is as follows:

Figure 103. Photo. Aerial view of site SC-2. This figure shows an aerial photo of the interchange of I-185 and I-385 with I-385 and US-276 in Mauldin, SC. The study limits along each route were drawn on the aerial photograph.
©2011 Google Earth®
Figure 103. Photo. Aerial view of site SC-2.(73)

 

Table 72. Characteristics of SC-2.
Variable NB SB EB WB
Study length (ft) 22,720 16,200 16,055 14,460
Number of concurrent routes 1 1 1 1
Number of levels 3 3 3 3
Number of missing movements 1 1 0 0
Number of ramps 4 3 3 4
Exit ramps per mile 0.70 0.65 0.33 0.73
Entrance ramps per mile 0.23 0.33 0.66 0.73
Left exits per mile 0.00 0.00 0.00 0.00
Left entrances per mile 0.00 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.65 0.33 0.37
Multilane exit ramps per mile 0.00 0.00 0.00 0.37
Optional/shared exit lanes per mile 0.46 0.33 0.00 0.37
Exit only lanes per mile 0.23 0.33 0.33 0.73
Score 260 255 200 370
Overall score 271.25

Information for site SC-3 is as follows:

Figure 104. Photo. Aerial view of site SC-3. This figure shows an aerial photo of the interchange of I-77 with US-21 in Rock Hill, SC. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 104. Photo. Aerial view of site SC-3.(74)

 

Table 73. Characteristics of SC-3.
Variable NB SB EB WB
Study length (ft) 20,390 19,460 0 0
Number of concurrent routes 1 1 0 0
Number of levels 2 2 0 0
Number of missing movements 0 0 0 0
Number of ramps 2 2 0 0
Exit ramps per mile 0.26 0.27 0 0
Entrance ramps per mile 0.26 0.27 0 0
Left exits per mile 0.00 0.00 0 0
Left entrances per mile 0.00 0.00 0 0
Number of exit ramps with multiple destinations per mile 0.26 0.27 0 0
Multilane exit ramps per mile 0.00 0.27 0 0
Optional/shared exit lanes per mile 0.26 0.27 0 0
Exit only lanes per mile 0.00 0.27 0 0
Score 115 270 - -
Overall score 192.5

- Indicates no score was generated because EB and WB approaches were not present.

Information for site VA-1 is as follows:

Figure 105. Photo. Aerial view of site VA-1. This figure shows an aerial photo of the interchange of I-95/I-395 Connector with I-495 in Springfield, VA. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 105. Photo. Aerial view of site VA-1. (75)

 

Table 74. Characteristics of VA-1.
Variable NB SB EB WB
Study length (ft) 8,850 11,130 22,230 21,005
Number of concurrent routes 1 1 1.5 1.25
Number of levels 4 4 4 4
Number of missing movements 0 0 0 0
Number of ramps 3 4 4 4
Exit ramps per mile 0.60 0.95 0.48 0.75
Entrance ramps per mile 1.19 0.95 0.48 0.25
Left exits per mile 0.00 0.00 0.00 0.25
Left entrances per mile 0.00 0.47 0.24 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.95 0.24 0.25
Multilane exit ramps per mile 0.60 0.95 0.48 0.25
Optional/shared exit lanes per mile 0.00 0.95 0.24 0.00
Exit only lanes per mile 1.19 1.42 0.95 1.01
Score 340 470 330 325
Overall score 366.25

Information for site VA-2 is as follows:

Figure 106. Photo. Aerial view of site VA-2. This figure shows an aerial photo of the interchange of I-395 with SR 27 in Washington, DC. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 106. Photo. Aerial view of site VA-2. (76)

Table 75. Characteristics of VA-2.
Variable NB SB EB WB
Study length (ft) 11,920 11,560 11,070 8,420
Number of concurrent routes 1 1 1 1.2
Number of levels 2 2 2 2
Number of missing movements 0 1 0 1
Number of ramps 6 5 10 12
Exit ramps per mile 1.77 0.46 1.91 2.51
Entrance ramps per mile 0.89 1.83 2.86 1.88
Left exits per mile 0.44 0.00 0.00 1.25
Left entrances per mile 0.00 0.46 0.48 0.00
Number of exit ramps with multiple destinations per mile 0.44 0.46 1.43 0.63
Multilane exit ramps per mile 0.00 0.00 0.95 0.63
Optional/shared exit lanes per mile 0.00 0.00 0.95 0.63
Exit only lanes per mile 1.77 0.46 1.91 3.14
Score 460 385 750 790
Overall score 596.25

Information for site VA-3 is as follows:

Figure 107. Photo. Aerial view of site VA-3. This figure shows an aerial photo of the interchange of I-664 with I-64, I-264, US-13, US-58, US-460, and SR 191 in Norfolk, VA. The study limits along each route were drawn on the aerial photograph.
©2010 Google Earth®
Figure 107. Photo. Aerial view of site VA-3.(77)

 

Table 76. Characteristics of VA-3.
Variable NB SB EB WB
Study length (ft) 23,105 19,080 8,165 10,960
Number of concurrent routes 1 1.143 2 1
Number of levels 2 2 2 2
Number of missing movements 0 0 0 0
Number of ramps 5 7 4 2
Exit ramps per mile 0.46 1.11 1.29 0.48
Entrance ramps per mile 0.69 0.55 1.29 0.48
Left exits per mile 0.00 0.00 0.00 0.48
Left entrances per mile 0.23 0.00 0.00 0.00
Number of exit ramps with multiple destinations per mile 0.00 0.00 0.00 0.00
Multilane exit ramps per mile 0.23 0.28 0.65 0.00
Optional/shared exit lanes per mile 0.00 0.00 0.00 0.00
Exit only lanes per mile 0.91 1.38 1.94 0.48
Score 330 415 345 210
Overall score 325

 

ACKNOWLEDGMENTS

The research reported herein was performed for FHWA by TTI. The authors wish to acknowledge the individuals who contributed to this research by participating in the simulation surveys, assisting with field study site selection, and serving as technical experts by providing feedback on which characteristics should be included in the spreadsheet tool.

The authors also wish to acknowledge those within TTI who assisted with the literature review and helped with data collection and reduction for either the simulator study or the decision tool. Those individuals include the following:

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