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From page 196... ... 196 A P P E N D I X E : F I N A L S T U D Y D E S I G N S Final Study Designs Introduction This appendix describes the final study design for three of the four high-priority access management (AM) techniques identified in Table 83 of Appendix C Read the entire page →
From page 197... ... 197 Table 107. Performance relationships planned for development – driveway design. Read the entire page →
From page 198... ... 198 The presence of on-street parking can have an adverse effect on driver sight distance to the driveway, especially if the parking stalls are located near the driveway and are often occupied by parked vehicles. The presence of a bicycle lane generally improves driver sight distance and can mitigate the negative effect of on-street parking on sight lines. Read the entire page →
From page 199... ... 199 Data Collection Plan This section describes the data collection plan for driveway design. The plan is focused on the collection and reduction of data needed to develop relationships describing the effect of driveway design on pedestrian and bicycle performance. Read the entire page →
From page 200... ... 200 Sample Size. Consideration of sampling statistics and project resources indicated that data were needed for at least 20 sites. Read the entire page →
From page 201... ... 201  About 1/2 of the sites should have a marked bicycle lane on the major street (and the others should have no marked lane) ;  At least 1/3 of the sites should have driveway left-turn prohibition on the major street (and the others should allow left turns into and out of the driveway) Read the entire page →
From page 202... ... 202 Data Reduction. Data reduction procedures were developed and documented. Read the entire page →
From page 203... ... 203 collected using two camcorders. The desired data were extracted from the videotape recordings during replay in the office. Read the entire page →
From page 204... ... 204 The research addressed right-turn deceleration lane presence at signalized intersections in urban areas. The addition of a right-turn lane is anticipated to change the safety and operation of the aforementioned five travel mode/performance categories. Read the entire page →
From page 205... ... 205 Category Data Element Data Need by Travel Mode Ped Bike (ops. only) Read the entire page →
From page 206... ... 206 the "before" condition. A second testbed was based on the "before" condition intersections but they included right-turn deceleration lanes to represent the "after" condition. Read the entire page →
From page 207... ... 207 Category Data Element Values Combinations Presence of turning roadway and triangular channelizing island no 1 Curb return radius 25 ft. 1 Presence of marked bicycle lane yes 1 Intersection skew angle 0 degrees (no skew) Read the entire page →
From page 208... ... 208 Table 112. Characteristics of the right-turn lane test bed – right-turn deceleration. Read the entire page →
From page 209... ... 209 The VISSIM simulation model was used in this project because it has the capability of simulating cars, pedestrians, bicycles, transit, and trucks. The plan for calibrating this model is discussed in a later section. Read the entire page →
From page 210... ... 210 together, the results can be compared to obtain information about the relative performance of the two techniques. Objectives and Scope The objective of this study was to develop operations and safety performance relationships describing the effect of TWLTLs and NTMs on select non-passenger-car travel modes on urban street segments bounded by signalized intersections. Read the entire page →
From page 211... ... 211 Table 114. Data elements possibly affecting performance – TWLTL vs. Read the entire page →
From page 212... ... 212 relationships describing the effect of TWLTL presence and NTM presence on bicycle, transit, and truck performance. The plan consists of two components. Read the entire page →
From page 213... ... 213 The values of the independent variables in the testbed were then changed, in conformance with the experimental design, to form supplemental input data sets. The test bed used for this study was based on the street segments used for model calibration, as described in a later section. Read the entire page →
From page 214... ... 214 Table 115. Characteristics of the TWLTL test bed – TWLTL vs. Read the entire page →
From page 215... ... 215 Table 116. Characteristics of the NTM test bed – TWLTL vs. Read the entire page →
From page 216... ... 216 length case, one scenario will include two right-in-right-out access points and two full-movement access points. A second scenario will include three right-in-right-out access points and three full-movement access points. Read the entire page →
From page 217... ... 217 Database Elements Data elements that may influence the effects of median type on transit and truck safety are listed in Table 114. Performance measures that should also be measured during the study period are identified in the following list. Read the entire page →
From page 218... ... 218  One-half of the sites should have a TWLTL and the other 1/2 should have a NTM. Study Design A wide variety of data was planned for assembly. Read the entire page →
From page 219... ... 219 Site Sample Size Consideration of sampling statistics and project resources indicate that calibration data were needed for at least eight sites. Four of the sites would be urban arterial street segments (one site is one direction of travel) Read the entire page →
From page 220... ... 220 Study Design VISSIM Calibration Field Data Description Field data were collected at the selected sites for the purpose of calibrating key parameters in the simulation model. One global set of calibration parameters was obtained from the collective set of sites. Read the entire page →
From page 221... ... 221 Application Category Data Element Data Need by Travel Mode Data Collection Approach Auto Ped Bicycle Transit Truck Right-turn-on-red allowance Needed in general (independent of mode) Video or timing sheets Control device Major street speed limit Needed in general (independent of mode) Read the entire page →
From page 222... ... 222 Subject Driveway 1 Major Street Camera 1 Bike Lane Camera 2 Subject Driveway 2 Bike Lane Bike Lane Intersection 1 Camera 4 Bike Lane Bike Lane Intersection 2 Camera 3 Sensor 1 Sensor 2 Sensor 3 Sensor 4 For a given travel mode, one "vehicle" class was established for each of the parameter sets established. A speed distribution was obtained from the data for each of these classes. Read the entire page →
From page 223... ... 223 Camera 4 Bike Lane Bike Lane Intersection 2 Sensor 4 Subject Driveway 2 Bike Lane Bike Lane Camera 3 Sensor 3 Figure 8. Camera location for intersection data collection – VISSIM calibration. Read the entire page →
From page 224... ... 224 Figure 7 illustrates this setup with two mid-segment driveways for one direction. Additional cameras were needed for longer sites. Read the entire page →
From page 225... ... 225 Simulation Data Description The field data needed to calibrate the SSAM software tool are identified in Table 118. These data include four different types of conflict for each of the truck and transit travel modes of interest. Read the entire page →
From page 226... ... 226 site-by-site basis. The process was repeated for a range of values for TCC and PET. Read the entire page →

From page 196...

... 196 A P P E N D I X E : F I N A L S T U D Y D E S I G N S Final Study Designs Introduction This appendix describes the final study design for three of the four high-priority access management (AM) techniques identified in Table 83 of Appendix C