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Appendix B Findings From Other NCHRP Datasets
NCHRP Project 3-37 â Merge Data Collection Sites The following plots contain data in averaged in 15 minute bins collected at merge sites as part of NCHRP Project 3-37. The data is presented in three different ways: ⢠Each 15-minute period classified as stable or unstable flow ⢠Each 15-minute period classified as being on a 2-, 3-, or 4-lane (one- way) freeway ⢠Each 15-minute period classified as having a low, moderate, or high entry ramp volume. Within each of these classifications, separate charts are provided for data in each LOS. Notes on the charts: ⢠LOS was measured upstream of the merge ramp and determined by the Project 3-37 researchers ⢠âSpeed between rampsâ is the minimum average speed measured by detectors located downstream of the merging ramp
Stable or Unstable Flow Sorted By: LOS A and B 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Stable Flow LOS C 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Stable Flow
LOS D 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Stable Flow Unstable Flow LOS E 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Stable Flow Unstable Flow LOS F 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Stable Flow Unstable Flow
Number of Freeway Lanes Sorted By: LOS A and B 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway LOS C 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway 4 Lane Freeway
LOS D 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway 4 Lane Freeway LOS E 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway 4 Lane Freeway LOS F 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway
Ramp Volume Sorted By: LOS A and B 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310) LOS C 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310)
LOS D 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310) LOS E 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310) LOS F 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to downstream EX Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310)
NCHRP Project 3-37 â Diverge Data Collection Sites The following plots contain data in averaged in 15 minute bins collected at diverge sites as part of NCHRP Project 3-37. The data is presented in three different ways: ⢠Each 15-minute period classified as stable or unstable flow ⢠Each 15-minute period classified as being on a 2-, 3-, or 4-lane (one- way) freeway ⢠Each 15-minute period classified as having a low, moderate, or high exit ramp volume. Within each of these classifications, separate charts are provided for data in each LOS. Notes on the charts: ⢠LOS was measured upstream of the diverge ramp (between the merge and diverge ramps) and determined by the Project 3-37 researchers ⢠âSpeed between rampsâ is the minimum average speed measured by detectors located downstream of the merging ramp
Stable or Unstable Flow Sorted by: LOS B and C 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps Stable Flow LOS D 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps Stable Flow Unstable Flow LOS E 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps Stable Flow
Number of Freeway Lanes Sorted by: LOS B and C 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway 4 Lane Freeway LOS D 0 10 20 30 40 50 60 70 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway 4 Lane Freeway LOS E 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps 2 Lane Freeway 3 Lane Freeway
Ramp Volume Sorted by: LOS B and C 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310) LOS D 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310) LOS E 0 10 20 30 40 50 60 70 0 5000 10000 15000 20000 Distance to upstream EN Sp ee d B et w ee n R am ps Low Vol Ramp (112-500) Mid Vol Ramp (508-918) High Vol Ramp (930-2310)
NCHRP Project 3-75 â Speed of all vehicles in weaving section (between ramps) The following plots contain data in averaged in 15 minute bins collected at as part of NCHRP Project 3-75. Each graph contains the complete set of data collected by the Project 3-75 researchers.
Sorted by # of Upstream Lanes 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps 2 Lanes 3 Lanes 4 lanes 5 Lanes 6 Lanes Sorted by On-Ramp Volume 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps Lowest Low High Highest Sorted by Off-Ramp Volume 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps Lowest Low High Highest
Sorted by Total Ramp Volume (on and off) 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps Lowest Low High Highest Sorted by Interchange Density 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps 1.33 to 1.50 2.17 to 2.50 2.67 to 3.83 Sorted by Weaving Type 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps Type A Type B Type C
Site Notes 2 - 2 lane exit Sky03 - cloverleaf Sky06 - 2 lane entry Sky09 - 2 lane exit Sky10 - 2 lane entry and 2 lane exit Sorted by Site 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps 1 Emeryville, CA (NGSIM 1) 2 Portland, OR 4 Los Angeles, CA (NGSIM 2a) Sky01 Miami, FL Sky03 Baltimore, MD Sky04 Baltimore, MD Sky05 Phoenix, AZ Sky06 Phoenix, AZ Sky07 Phoenix, AZ Sky08 Portland, OR Sky09 Portland, OR Sky10 Portland, OR Sorted by FFS 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps 56 62 65 67 68 70 71
NCHRP Project 3-75 â Reduction in free-flow speed of all vehicles in weaving section (between ramps)
Sorted by # of Upstream Lanes 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d R ed uc tio n B et w ee n R am ps 2 Lanes 3 Lanes 4 lanes 5 Lanes 6 Lanes Sorted by On-Ramp Volume 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d R ed uc tio n B et w ee n R am ps Lowest Low High Highest Sorted by Off-Ramp Volume 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d R ed uc tio n B et w ee n R am ps Lowest Low High Highest
Sorted by Total Ramp Volume (on and off) 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d R ed uc tio n B et w ee n R am ps Lowest Low High Highest Sorted by Interchange Density 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d R ed uc tio n B et w ee n R am ps 1.33 to 1.50 2.17 to 2.50 2.67 to 3.83 Sorted by Weaving Type 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d R ed uc tio n B et w ee n R am ps Type A Type B Type C
Site Notes 2 - 2 lane exit Sky03 - cloverleaf Sky06 - 2 lane entry Sky09 - 2 lane exit Sky10 - 2 lane entry and 2 lane exit Sorted by Site 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps 1 Emeryville, CA (NGSIM 1) 2 Portland, OR 4 Los Angeles, CA (NGSIM 2a) Sky01 Miami, FL Sky03 Baltimore, MD Sky04 Baltimore, MD Sky05 Phoenix, AZ Sky06 Phoenix, AZ Sky07 Phoenix, AZ Sky08 Portland, OR Sky09 Portland, OR Sky10 Portland, OR Sorted by FFS 0.0 10.0 20.0 30.0 40.0 50.0 0 500 1000 1500 2000 2500 3000 Ramp Spacing (Base Length) Sp ee d B et w ee n R am ps 56 62 65 67 68 70 71
