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From page 150... ... 150 A P P E N D I X D : I N I T I A L S T U D Y D E S I G N S Initial Study Designs Introduction This appendix documents the initial study designs developed for each of the 20 AM techniques identified in Table 74 (of Appendix C) Read the entire page →
From page 151... ... 151 Table 84. Study design for traffic signal spacing. Read the entire page →
From page 152... ... 152 Performance Measures The performance measures are listed in Table 84. These performance measures will be obtained from the aforementioned data sources. Read the entire page →
From page 153... ... 153 Table 85. Study design for access point spacing. Read the entire page →
From page 154... ... 154 As a second choice, crash data may be acquired for a large number of locations where different unsignalized intersection spacing can be found. These data will then be evaluated to determine if there are sufficient mode-specific crashes to quantify a performance relationship. Read the entire page →
From page 155... ... 155 Table 86. Study design for corner clearance. Read the entire page →
From page 156... ... 156 Performance Measures The performance measures for the transit and truck travel modes are listed in the last column of Table 86. These performance measures will be obtained from the aforementioned data sources. Read the entire page →
From page 157... ... 157 Table 87. Study design for non-traversable median. Read the entire page →
From page 158... ... 158 Performance Measures The performance measures are listed in the last column of Table 87. These performance measures will be obtained from the aforementioned data sources. Read the entire page →
From page 159... ... 159 Table 88. Study design for closing existing median openings. Read the entire page →
From page 160... ... 160 Safety Data Source Reported crashes will be the source for safety data. A number of corridors will be identified and studied that have had median openings closed in the recent past These data will then be evaluated to determine if there are sufficient pedestrian-, transit-, and truck-related crashes to quantify a performance relationship. Read the entire page →
From page 161... ... 161 Table 89. Study design for replacing a full median opening with a median designed for left turns from the major roadway. Read the entire page →
From page 162... ... 162 Safety Data Source Simulation-based conflicts will be the first-choice source for safety data. The same testbed assembled for the operations data will be used to acquire the safety data. Read the entire page →
From page 163... ... 163 Table 90. Study design for installation of a continuous TWLTL on an undivided highway. Read the entire page →
From page 164... ... 164 volume is unlikely to be available or cost-effective to measure so adjacent land use will be used as a surrogate for this volume. Performance Measures The performance measures are listed in the last column of Table 90. Read the entire page →
From page 165... ... 165 Table 91. Study design for median U-turns as an alternative to direct left turns. Read the entire page →
From page 166... ... 166 turns will be added to the testbed to represent the "after" condition. Key independent variables that may influence the effects of this access management technique on operations are listed in Table 91. Read the entire page →
From page 167... ... 167 Table 92. Study design for installation of a right-turn deceleration lane. Read the entire page →
From page 168... ... 168 Safety Data Source Simulation-based conflicts will be the first-choice source for safety data. The same testbed used for the operations data will be used to acquire the safety data. Read the entire page →
From page 169... ... 169 Table 93. Study design for installation of a continuous right-turn lane. Read the entire page →
From page 170... ... 170 Safety Data Source Reported crashes will be the source for safety data. A number of street segments will be identified and studied that in the recent past have had a continuous right-turn lane installed. Read the entire page →
From page 171... ... 171 Table 94. Study design for consolidate driveways. Read the entire page →
From page 172... ... 172 needed to assess the strength of the connection between the conflict measures obtained from simulation and crash frequency or severity. If a strong connection is not identified in the literature, then some project resources may be needed to establish the relationship using crash data. Read the entire page →
From page 173... ... 173 Table 95. Study design for channelizing driveways to discourage or prohibit left turns. Read the entire page →
From page 174... ... 174 Safety Data Source Simulation-based conflicts will be the first-choice source for safety data. A simulation testbed will be established using several prototype unsignalized intersections formed by a public road and one or two driveway approaches. Read the entire page →
From page 175... ... 175 Table 96. Study design for intersection spacing on interchange crossroad. Read the entire page →
From page 176... ... 176 crashes to quantify a performance relationship. Pedestrian and bicycle volume are unlikely to be available or cost-effective to measure so adjacent land use will be used as a surrogate for these volumes. Read the entire page →
From page 177... ... 177 Table 97. Study design for installation of median barrier with no direct left-turn ingress or egress. Read the entire page →
From page 178... ... 178 Safety Data Source Simulation-based conflicts will be the first-choice source for safety data. The same testbed assembled for the operations data will be used to acquire the safety data. Read the entire page →
From page 179... ... 179 Table 98. Study design for moving the sidewalk crossing of a driveway away from the roadway. Read the entire page →
From page 180... ... 180 Safety Data Source It will be necessary to collect field data in order to evaluate the safety effects of this access management technique. The same sites used for the operations data source will also be used as the safety data source, and in this case the sites will be examined with respect to their safety performance characteristics. Read the entire page →
From page 181... ... 181 Table 99. Study design for requiring access on collector instead of a nearby highway. Read the entire page →
From page 182... ... 182 independent variables that may influence the effects of this access management technique on operations are listed in Table 99. Safety Data Source Simulation-based conflicts will be the first-choice source for safety data. Read the entire page →
From page 183... ... 183 Table 100. Study design for relocation or reorientation of an access point. Read the entire page →
From page 184... ... 184 Safety Data Source Simulation-based conflicts will be the first-choice source for safety data. The same testbed assembled for the operations data will be used to acquire the safety data. Read the entire page →
From page 185... ... 185 Table 101. Study design for removing curb parking. Read the entire page →
From page 186... ... 186 crashes to quantify a performance relationship. Pedestrian volume is unlikely to be available or costeffective to measure so adjacent land use will be used as a surrogate for this volume. Read the entire page →
From page 187... ... 187 Table 102. Study design for installation of a roundabout. Read the entire page →
From page 188... ... 188 simulation and crash frequency or severity. If a strong connection is not identified in the literature, then some project resources may be needed to establish the relationship using crash data. Read the entire page →
From page 189... ... 189 Table 103. Study design for improve driveway sight distance. Read the entire page →
From page 190... ... 190 Safety Data Source Field data will also be necessary to evaluate safety. The same sites used for the operations data source will also be used as the safety data source. Read the entire page →
From page 191... ... 191 Table 104. Study design for driveway design. Read the entire page →
From page 192... ... 192 pedestrian-related and bicycle-related crashes to quantify a performance relationship. This option may require a relatively large amount of project resources. Read the entire page →
From page 193... ... 193 Table 105. Study design for TWLTL vs. Read the entire page →
From page 194... ... 194 Safety Data Source Reported crashes will be the source for safety data. A number of corridors will be studied that have either a TWLTL or a non-traversable median. Read the entire page →
From page 195... ... 195 Table 106. Study design for corner clearance (revised) Read the entire page →

From page 150...

... 150 A P P E N D I X D : I N I T I A L S T U D Y D E S I G N S Initial Study Designs Introduction This appendix documents the initial study designs developed for each of the 20 AM techniques identified in Table 74 (of Appendix C)