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From page 50... ... TCRP Web-Only Document 53 46 CHAPTER 4: MODELING/SIMULATION OF LIGHT RAIL OPERATING CONDITIONS: NORTH FIRST STREET FROM EAST BROKAW ROAD TO TRIMBLE ROAD INTRODUCTION Objectives: The objective of this study was to develop a micro-simulation model for the Light Rail corridor on North Frist St. from East Brokaw Road to Trimble Road in San Jose, California in order to analyze the simulated intersection safety under existing and suggested conditions (increasing LRV operating speed from 35 mph to 45 mph) Read the entire page →
From page 51... ... TCRP Web-Only Document 53 47 The VISSIM™ model consists internally of two distinct components: the traffic simulator and the signal state generator. These components are constantly communicating detector calls and signal status to each other through an interface. Read the entire page →
From page 52... ... TCRP Web-Only Document 53 48 Figure 14. VISSIM Network Model N First Street at Trimble Rd N First Street at Component N First Street at Charcot Ave N First Street at Karina Ct N First Street at E Brokaw Rd Northbound LRT Stop #1 Northbound LRT Stop #2 Southbound LRT Stop #1 Southbound LRT Stop #2 Southbound LRT Stop #3 Read the entire page →
From page 53... ... TCRP Web-Only Document 53 49 crossing ungated intersections. A linear distribution was assigned, which ranged from 34.5 to 35.5 mph. Read the entire page →
From page 54... ... TCRP Web-Only Document 53 50 122 913 130 39 800 261 118 1018 122 222 425 69 22 1011 44 48 12 123 14 22 29 21 597 26 527 758 93 37 593 107 203 216 131 383 62 81 8 1025 8 31 0 147 600 256 255 930 224 186 918 463 314 840 60 53 330 295 23 303 61 43 958 305 194 701 140 238 919 153 35 568 70 30 36 43 3 15 3 34 1158 82 192 322 39 55 178 61 495 519 117 768 113 8 13 375 12 5 0 354 1089 18 120 231 85 385 1072 329 542 672 83 106 660 309 PM Peak AM Peak adequate lane changing distance, the routing decisions were placed according to the observed driver behavior in the model, and adjusted so that vehicles had adequate time to make the decision to change lanes to reach their desired destination. Because origin-destination data was not obtained, as it is not crucial to the purpose of this study, routing decisions were placed following each intersection, so that all of the source links feed the destination links proportionately. Read the entire page →
From page 55... ... TCRP Web-Only Document 53 51 Vehicle Types and Compositions Based on the available data and observations recorded and made in the field, a system wide composition was assigned to all input links which included 96% Cars, 3% Trucks, and 1% Buses. Independent bicycle volumes were assigned, as were pedestrian volumes at each intersection. Read the entire page →
From page 56... ... TCRP Web-Only Document 53 52 BASE CONDITION ANALYSIS Following the development of the base condition model in VISSIM, trajectory files were output for processing in SSAM. Five 5-hour simulations were run per peak period, with peak hour volumes input for each of the five hours. Read the entire page →
From page 57... ... TCRP Web-Only Document 53 53 Crossing Rear End Lane Change N First St at E Brokaw 2407 11 2287 109 N First St at Karina Ct 523 0 486 37 N First St at Charcot Ave 1337 3 1295 39 N First St at Component Dr 1020 8 986 26 N First St at Trimble Rd 1824 4 1742 78 Type of Conflict Intersection Total Conflicts AM Peak Period Conflicts (5 simulations of 5 hours each) Crossing Rear End Lane Change 1 432 5 409 18 2 499 1 482 16 3 486 4 458 24 4 490 1 470 19 5 500 0 468 32 Total 2407 11 2287 109 Average 481 2 457 22 St. Read the entire page →
From page 58... ... TCRP Web-Only Document 53 54 Crossing Rear End Lane Change N First St at E Brokaw 2942 6 2831 105 N First St at Karina Ct 1235 4 1147 84 N First St at Charcot Ave 1465 4 1365 96 N First St at Component Dr 465 4 446 15 N First St at Trimble Rd 1781 8 1714 59 Type of Conflict Intersection Total Conflicts PM Peak Period Conflicts (5 simulations of 5 hours each) Crossing Rear End Lane Change 1 579 0 559 20 2 577 1 556 20 3 605 1 583 21 4 595 2 574 19 5 586 2 559 25 Total 2942 6 2831 105 Average 588 1 566 21 St. Read the entire page →
From page 59... ... TCRP Web-Only Document 53 55 ALTERNATIVE ANALYSIS The tasks below were the focus of the alternatives that were developed and analyzed: Task 7. Code an alternative speed increase for 40 mph and optimize signal timing (left-turn phase sequence and offsets) Read the entire page →
From page 60... ... TCRP Web-Only Document 53 56 travel times, the additional time spent accelerating and decelerating from higher speeds was taken into consideration. Figure 18 shows the values assigned in adjusting the detector parameters. Read the entire page →
From page 61... ... TCRP Web-Only Document 53 57 Intersection with N First St Detector Number (Assigned In VISSIM model) Track Direction Existing Distance to Intersection Existing Travel Time Proposed Travel Time (40 mph) Read the entire page →
From page 62... ... TCRP Web-Only Document 53 58 No Significant Change Significant Decrease Significant Increase Legend vehicle speed (four volume alternatives, two speed alternatives, and two peak periods) , there were no recorded conflicts involving Light Rail Vehicles. Read the entire page →
From page 63... ... TCRP Web-Only Document 53 59 No Significant Change Significant Decrease Significant Increase Legend AM 40 mph 0 Percent AM 40 mph 10 Percent AM 40 mph 15 Percent AM 40 mph 20 Percent AM 45 mph 0 Percent AM 45 mph 10 Percent AM 45 mph 15 Percent AM 45 mph 20 Percent Existing AM (35 mph) -1.01 -5.208 -7.406 -9.887 -1.031 -4.988 -5.852 -10.308 AM 40 mph 0 Percent -4.435 -6.891 -9.562 0.053 -4.179 -5.202 -10.155 AM 40 mph 10 Percent -3.917 -7.755 5.134 0.769 -2.22 -9.414 AM 40 mph 15 Percent -5.105 7.972 5.244 0.075 -5.527 AM 40 mph 20 Percent 10.568 8.74 3.697 1.549 AM 45 mph 0 Percent -4.91 -5.659 -11.783 AM 45 mph 10 Percent -2.742 -11.693 AM 45 mph 15 Percent -3.117 Existing AM (35 mph) Read the entire page →
From page 64... ... TCRP Web-Only Document 53 60 No Significant Change Significant Decrease Significant Increase Legend Figure 20. PM Peak Hour Conflicts t-test PM 40 mph 0 Percent PM 40 mph 10 Percent PM 40 mph 15 Percent PM 40 mph 20 Percent PM 45 mph 0 Percent PM 45 mph 10 Percent PM 45 mph 15 Percent PM 45 mph 20 Percent Existing PM (35 mph) Read the entire page →
From page 65... ... TCRP Web-Only Document 53 61 No Significant Change Significant Decrease Significant Increase Legend Figure 7. (Continued) PM Peak Hour Conflicts t‐test PM 40 mph 0 Percent PM 40 mph 10 Percent PM 40 mph 15 Percent PM 40 mph 20 Percent PM 45 mph 0 Percent PM 45 mph 10 Percent PM 45 mph 15 Percent PM 45 mph 20 Percent Existing PM (35 mph) Read the entire page →
From page 66... ... TCRP Web-Only Document 53 62 Figure 21. AM Peak Hour Total Conflicts Read the entire page →
From page 67... ... TCRP Web-Only Document 53 63 Figure 22. AM Peak Hour Rear-end Conflicts Read the entire page →
From page 68... ... TCRP Web-Only Document 53 64 Figure 23. AM Peak Hour Lane Change Conflicts Read the entire page →
From page 69... ... TCRP Web-Only Document 53 65 Figure 24. PM Peak Hour Total Conflicts Read the entire page →
From page 70... ... TCRP Web-Only Document 53 66 Figure 25. PM Peak Hour Crossing Conflicts Read the entire page →
From page 71... ... TCRP Web-Only Document 53 67 Figure 26. PM Peak Hour Rear-end Conflicts Read the entire page →
From page 72... ... TCRP Web-Only Document 53 68 Figure 27. PM Peak Hour Lane Change Conflicts Read the entire page →
From page 73... ... TCRP Web-Only Document 53 69 Critical Observations and Changes In the processing of conflicts involving automobiles, pedestrians, and bicycles (there were no LRV conflicts recorded) , it is important to note the changes made to alternative conditions that may influence conflicts, as well as observations made in all of the models which may explain increases and decreases in conflicts between alternatives. Read the entire page →
From page 74... ... TCRP Web-Only Document 53 70 existing conditions results, in that East Brokaw St. and Trimble Road have the greatest number of conflicts and risky behavior. Read the entire page →
From page 75... ... TCRP Web-Only Document 53 71 models with a 10% increase in cross-street volumes and left-turn demand, there was a significant increase in total conflicts, rear-end conflicts, and lane-change conflicts. Read the entire page →
From page 76... ... TCRP Web-Only Document 53 72 occurred, it was either on a cross-street, or upstream from the intersection at which the spillback occurred. There were no instances observed of excessive queues backing onto the light rail crossings. Read the entire page →
From page 77... ... TCRP Web-Only Document 53 73 (27) Read the entire page →
From page 78... ... TCRP Web-Only Document 53 74 Figure 29. AM Peak Delays and Queues for Scenario with 45 mph LRV and 20% Turning Volume Increase vs. Read the entire page →
From page 79... ... TCRP Web-Only Document 53 75 Figure 30. PM Peak Delays and Queues for Scenario with 45 mph LRV and 20% Turning Volume Increase vs. Read the entire page →
From page 80... ... TCRP Web-Only Document 53 76 Figure 31. PM Peak Delays and Queues for Scenario with 45 mph LRV and 20% Turning Volume Increase vs. Read the entire page →
From page 81... ... TCRP Web-Only Document 53 77 PRELIMINARY CONCLUSIONS The results of the simulation did not demonstrate any change or significant evidence of an increase in LRV-related conflicts that are associated with increasing the operating speed of light rail vehicles. Likewise, the increase in the number of crossing type conflicts did not demonstrate a statistical significance among the various scenarios associated with increases in LRV speeds and traffic volumes. Read the entire page →

From page 50...

... TCRP Web-Only Document 53 46 CHAPTER 4: MODELING/SIMULATION OF LIGHT RAIL OPERATING CONDITIONS: NORTH FIRST STREET FROM EAST BROKAW ROAD TO TRIMBLE ROAD INTRODUCTION Objectives: The objective of this study was to develop a micro-simulation model for the Light Rail corridor on North Frist St. from East Brokaw Road to Trimble Road in San Jose, California in order to analyze the simulated intersection safety under existing and suggested conditions (increasing LRV operating speed from 35 mph to 45 mph)