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Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Page 110
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Page 111
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Page 112
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Page 113
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
Page 113
Page 114
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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Page 115
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
×
Page 115
Page 116
Suggested Citation:"Appendix D: Testing Plan." National Academies of Sciences, Engineering, and Medicine. 2012. Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH. Washington, DC: The National Academies Press. doi: 10.17226/22822.
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TCRP Web-Only Document 53 105 APPENDIX D: TESTING PLAN

TCRP Web-Only Document 53 106 As stated in the amplified work plan for this research project, two of the objectives of the research are to:  “Identify potential supplemental safety measures for use with traffic signals in lieu of highway-light rail grade crossing flashing lights and gates where LRVs could operate at speeds in excess of 35 mph in a semi-exclusive public right-of-way”; and  “Test higher-speed LRV operation (above 35 mph) at selected locations using identified supplemental safety measures.” This chapter outlines the testing plan that could be implemented if the agency had agreed to participate. The testing plan provides an overview of the test, defines the roles and responsibilities of the participating agencies and the research team, and describes the details of the various components of the test. While the details of the test plan focus on testing in San Jose, it can be modified for application in other agencies. Overview of Test The goal of the test is to assess the impacts of higher LRV speeds through selected crossings, equipped with supplemental safety measures, along a 1-mile segment of the North First St. corridor in San Jose, CA. Maximum LRV speeds in this segment of the corridor are currently 35 mph. The test will include implementation of a number of supplemental safety measures at three “test” crossings and an increase in the maximum LRV speed to 40 mph in the corridor, but specifically through the test crossings. Test crossings include:  North First St. and Brokaw Rd.;  North First St. and Charcot Ave.; and  North First St. and Trimble Rd. All three intersections are being implemented with supplemental / alternative traffic control devices. Higher speeds will be tested at all three locations in the northbound and southbound directions. The testing period will extend from approximately September 2009 through May 2011. The supplemental safety devices will be tested with a 35 mph LRV speed limit for a 9-month period from approximately September 2009 through May 2010. Increased LRV speeds of 40 mph will be tested for a 12-month period from approximately June 2010 through May 2011. The test will be implemented by the VTA and the City of San Jose. A simultaneous evaluation of the test will be conducted by the SAIC team (the evaluation plan is described in the following chapter). Roles and Responsibilities The lead agency implementing the test will be the VTA. The VTA will be supported by the City of San Jose and the SAIC team throughout the test. This section lists the roles and responsibilities of each organization. Details of each aspect of the testing program are described in the following section. SAIC Team Roles and Responsibilities The SAIC team will assist the VTA and the City of San Jose in the following activities:

TCRP Web-Only Document 53 107  Prepare letter to FHWA requesting permission to experiment with alternative traffic control devices as well as an increase in LRV speeds to 40 mph. A copy of the letter can be found in Appendix B.  Prepare application package to the California Public Utilities Commission (CPUC) requesting permission to deviate from the 35 mph maximum LRV speed.  Specify traffic signal timing requirements to allow for an increase in LRV speeds from 35 to 40 mph. VTA Roles and Responsibilities The roles and responsibilities of the VTA include the following activities:  Install supplemental and alternative safety measures / traffic control devices at the test intersections within the specified timeframe;  Prepare and train operators for the increase in speed during the 1-year testing period;  Notify the public, as deemed necessary, of the demonstration test;  Make necessary infrastructure modifications to allow for the speed increase, for example:  Sign the tracks for 40 mph speed;  Relocate detectors as necessary; and  Assure sufficient stopping sight distance. City of San Jose Roles and Responsibilities The City of San Jose’s primary roles and responsibilities will be to:  Modify the signal timing as necessary to allow for higher speed LRT operations; and  Provide crash data to the SAIC team every 3 months throughout the testing and evaluation period. Details of Testing Program This section describes the details of the various aspects of the testing program. Supplemental Safety Measures and Alternative Traffic Control Devices The VTA is in the process of enhancing the safety of a number of crossings with a variety of supplemental safety measures and alternative traffic control devices. Specifically, these enhancements include:  Relocation of existing stop bars in left-turn lanes adjacent to LRT tracks 20’ back from the crosswalk (or existing location) to enhance the visibility of an approaching LRT vehicle by left-turning traffic;  Use of “KEEP CLEAR” pavement markings on left-turn lanes (between the relocated stop bar and the crosswalk / intersection) adjacent to the LRT tracks to reinforce stopping at the stop bar;  Installation of yellow painted channelization pavement markings and yellow pavement markers around the tracks on the near and far sides of the intersection to promote appropriate lane tracking through the intersection to limit inappropriate track intrusions;

TCRP Web-Only Document 53 108  Installation of California Type Q Markers along the tracks in the vicinity of the crossings to guide vehicles away from the tracks during left turns from both the parallel and cross- streets; and  Installation of an alternating Train Approaching (W10-7) / No Left Hand Turn blank-out sign for parallel left-turning vehicles to signify when LRT vehicles are approaching the crossing. Phase I of the VTA’s improvements includes nine intersections, three of which are located within the 1-mile test segment of the North First St. corridor:  North First St. and Brokaw Rd.;  North First St. and Charcot Ave.; and  North First St. and Karina Ct. The construction at all nine intersections is expected to be complete by September 2009. Phase II of the VTA’s improvements include installation of the safety improvements at a number of additional intersections, including one within the 1-mile test segment along North First St.:  North First St. and Trimble Rd. Phase II construction is expected to begin in the spring of 2010 and be complete by summer. The VTA has indicated that they can request that the intersection of North First St. and Trimble Rd. be moved to the beginning of the construction schedule to allow for the testing of the higher speeds to be implemented by summer 2010. Infrastructure Modifications The VTA will make the necessary infrastructure modifications to support an increase in train speeds from 35 to 40 mph. Examples of infrastructure modifications that may be necessary include:  Sign the tracks for 40 mph speed—currently the tracks are signed for a maximum speed of 35 mph. To indicate to the LRV operators when 40 mph speeds are permitted, the VTA may need to install new signs along the trackways. This will include replacing all speed signs currently used with the 35 mph zone with new signs associated with the 40 mph zone.  Relocate detectors as necessary—Current detection of light rail vehicles at all study intersections is based on a maximum speed of 35 mph, and uses track circuits in advance of each intersection. Therefore, changing the approach speed to 40 mph may require relocation of the track circuits in order to provide earlier detection.  Assure sufficient stopping sight distance—At a minimum, the current stopping sight distance for light rail vehicles is based on a 35 mph running speed. Changing the approach speed to 40 mph will require a longer stopping sight distance to stop safely in the event the light rail signal display on the approach and at the intersection are malfunctioning or the signal timing at the intersection is not working properly. Therefore, the VTA will need to check all track visual aids and stopping sight distances at each approach of the three intersections to ensure adequate stopping sight distance from a speed of 40 mph.

TCRP Web-Only Document 53 109 Signal Timing Modifications The SAIC team will work with the City of San Jose to determine signal timing requirements to support an increase in train speeds from 35 to 40 mph. Increasing the speed of trains to 40 mph at the study intersections will require a longer window of opportunity for trains to cross, thus requiring longer green time on North First St. Train operators should see a vertical bar signal several seconds before they enter the intersection, thus allowing the train to continue moving at 40 mph without any hesitation. This window of opportunity may require the vertical bar signal to be displayed at least 10 to12 seconds prior to the train arrival. Train movements can overlap with the through movements on North First St., but the left-turn movements must terminate before the train receives the vertical bar signal. The City of San Jose is currently developing new signal timing plans for North First St., and the SAIC team will coordinate the development of the signal timing plans with the City to accommodate a provision for the higher train speed. Currently, no change in cycle length or in the left-turn phase sequence at any of the three intersections is anticipated. Operator Training One of the biggest issues in early discussions with the VTA and the City of San Jose was train operator behavior and the variability in travel times between stations. The City of San Jose bases the signal timing in part on the average LRV travel times between stations. The City noted that there was a large variability between operators. The VTA noted that this variability is likely due to the signal priority given to the LRT (i.e., predictive priority) and that the operators are not guaranteed to receive a go bar when approaching a crossing. In response to this issue, as well as the general issue of raising the maximum speed above what has been customary, it will be necessary to provide some form of training to the operators. The VTA will provide this training to operators prior to the implementation of the test. Community Outreach Prior to the implementation of the test, it may be necessary to conduct public outreach to let local drivers know that the trains will be operating at slightly higher speeds. It will be up to the VTA to determine if community outreach is necessary, and if so, in what format. The VTA will be responsible for conducting the public outreach. Increase LRV Speeds to 40 MPH Figure 32 illustrates the North First St. corridor where the increase in LRV speeds will take place. The figure shows six test segments, three in the northbound direction and three in the southbound direction.

TCRP Web-Only Document 53 110 Figure 32. Graphical Representation of the Four Test Segments along the North First St. Corridor Test Segment 1 begins at the intersection of North First St. and Old Bayshore Hwy. and stretches north to the Karina station, a distance of about 2,000 feet. Northbound LRVs will leave the

TCRP Web-Only Document 53 111 Metro / Airport station, accelerating to 35 mph through the crossing at Old Bayshore Hwy. Once the train has passed through the crossing at Old Bayshore Hwy., the train operator can accelerate to 40 mph prior to and through the crossing at Brokaw Rd. Once through the crossing at Brokaw Rd., the train operator will begin decelerating in preparation to stop at the Karina station. As the required stopping distance from 40 mph is estimated to be approximately 400 feet3, the train operator will be able to maintain a speed of 40 mph for approximately 1600 feet. The 5 mph difference in speed over this distance equates to approximately 4 seconds of travel time savings between the two stations. Test Segment 2 begins at the northbound Karina station and stretches north to the Component station, a distance of about 2,950 feet. Northbound LRVs will leave the Karina station, accelerating to 40 mph prior to and through the crossing at Charcot Ave. At some distance downstream of the crossing at Charcot Ave., the train operator will begin decelerating in preparation to stop at the Component station. As the required distance to accelerate to 40 mph is estimated to be approximately 425 feet,4 and the stopping distance from 40 mph is estimated to be approximately 400 feet, the train operator will be able to maintain a speed of 40 mph for approximately 2,125 feet in this segment. The 5 mph difference in speed over this distance equates to approximately 5 seconds of travel time savings between the two stations. Test Segment 3 begins at the northbound Component station and stretches north to the Bonaventura station, a distance of about 2,100 feet. Northbound LRVs will leave the Component station, accelerating to 40 mph prior to and through the crossing at Trimble Rd. Once through the crossing at Trimble Rd, the train operator will begin decelerating in preparation to stop at the Bonaventura station. As the required distance to accelerate to 40 mph is estimated to be approximately 425 feet, and the required stopping distance from 40 mph is estimated to be approximately 400 feet, the train operator will be able to maintain a speed of 40 mph for approximately 1,275 feet. The 5 mph difference in speed over this distance equates to approximately 3 seconds of travel time savings between the two stations. Test Segment 4 begins at the southbound Bonaventura station and stretches south to the Component station, also a distance of about 2,100 feet. Southbound LRVs will leave the Bonaventura station, accelerating to 40 mph just as they pass through the crossing at Trimble Rd. At some point downstream of the crossing at Trimble Rd., the train operator will begin to decelerate in preparation to stop at the Component station. As the required distance to accelerate to 40 mph is estimated to be approximately 425 feet, and the required stopping distance from 40 mph is estimated to be approximately 400 feet, the train operator will be able to maintain a speed of 40 mph for approximately1,275 feet. The 5 mph difference in speed over this distance equates to approximately 3 seconds of travel time savings between the two stations. Test Segment 5 begins at the southbound Component station and stretches south to the Karina station, a distance of about 2,975 feet. Southbound LRVs will leave the Component station, accelerating to 40 mph prior to and through the crossing at Charcot Ave. At some point downstream of the crossing at Charcot Ave, the train operator will begin to decelerate in preparation to stop at the Karina station. As the required distance to accelerate to 40 mph is estimated to be approximately 425 feet, and the required stopping distance from 40 mph is 3 The estimated distance of 400 feet to decelerate from 40 mph is based on a deceleration rate of 3 mph per second (mphps). 4 The estimated distance of 425 feet to accelerate to 40 mph is based on an acceleration rate of 2.75 mphps.

TCRP Web-Only Document 53 112 estimated to be approximately 400 feet, the train operator will be able to maintain a speed of 40 mph for approximately 2,150 feet. The 5 mph difference in speed over this distance equates to approximately 5 seconds of travel time savings between the two stations. Test Segment 6 begins at begins at the southbound Karina station and stretches south to the Metro / Airport station, a distance of about 2,325 feet. Southbound LRVs will leave the Karina station, accelerating to 40 mph just as they pass through the crossing at Brokaw Rd. Approximately 700 feet downstream of the crossing at Brokaw Rd., the train operator will need to decelerate to 35 mph before entering the crossing at Old Bayshore Hwy. Therefore, the train operator will be able to maintain a speed of 40 mph for approximately 900 feet. The 5 mph difference in speed over this distance equates to approximately 2 seconds of travel time savings between the two stations.

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 Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH
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TRB’s Transit Cooperative Research Program (TCRP) Web-Only Document 53: Operation of Light Rail Transit through Ungated Crossings at Speeds over 35 MPH presents the findings of a micro-simulation modeling study that explored the impacts of higher light rail vehicle speeds on intersection safety.

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