At-Grade Intersections Near Highway-Railroad Grade Crossings

The design of at-grade intersections near highway-railroad grade crossings is challenging because of the interaction between the two geometric features. Their designs can have a critical effect on safety and operation at both features. These guidelines provide information helpful in the following specific areas: traffic control devices, signal interconnection, channelization, high-profile or "hump" crossings, and illumination.

2001

Texas leads the nation in both the number of at-grade crossings and the number of incidents at those crossings. A large number of design and operational elements intended to provide information to the driver or control the driver's behavior are present in at-grade crossings and intersections. For this reason, at grade intersections near highway-railroad grade crossings can cause driver confusion and add to traffic safety concerns. Current design guidelines address at-grade intersection design and highway-railroad grade crossings, but generally do not address the case where the two are in close proximity. This project was initiated to identify items that should be considered in designing at-grade intersections near highway-railroad grade crossings.

The coordination of highway-railroad grade crossing warning signals with nearby traffic signals is of vital importance due to potential safety consequences. Interconnections between traffic signals in close proximity to railroad crossings provide an important safety function by allowing the railroad warning system to preempt the normal traffic signal operation and provide special phasing to clear vehicles queued over the railroad tracks, prohibit others from joining the queue, and maintaining traffic flow for non-conflicting traffic movements. In Michigan, there are approximately 200 interconnected highwayrailroad grade crossings that are all under regulatory control of the Michigan Department of Transportation. The MUTCD provides guidance concerning the use of preemption where the signalized intersection is within 200 feet of a railroad crossing. There is however, minimal guidance for locations where intersections are more than 200 feet beyond the railroad crossings. Some of these locations experience queuing problems due to high traffic volumes. The purpose of this research was to compile and review literature and current practices related to interconnected traffic signals and preemption in order to determine solutions for providing safe and efficient timings for the traffic signals and nearby highway-railroad grade crossing warning signals. A series of highway-railroad intersection configuration templates was developed as a part of this research. A set of guidelines was also developed with accompanying software to provide additional assistance for identification of possible interconnection locations that could utilize preemption concepts. The guidelines also assist in the determination of signal timing parameters for the phasing and timing design required as a part of the concept.

2017

For this proposal, a highly qualified team has been assembled with two professionals from a university (SUNY Buffalo) and a consulting company (KLD), respectively. To conduct the research task, the research team combines expertise of traffic signal control and railway safety. A brief summary of the qualifications of the two key members of the research team and their relevant research experience is given below.

Path Research Report, 2010

Reports on an in-depth study of problems associated with grade crossings configured with an adaptive trolley signal priority (ATSP) system. The system is designed for large-scale field implementation of the ATSP System and consists of three subsystems: an onboard subsystem , a roadside control subsystem and a central control subsystem. Laboratory design testing was conducted on the proposed ATSP system prior to a preliminary field operational testing (FOT) of the system in San Diego. These tests are used to demonstrate the applicability of the FOT. The proposed system utilizes the QuicNet/4 central control system as used in the San Diego Transportation Management Center (TMC) and Type 170 controllers at the roadside. Overall performance of the proposed ATSP system was not as successful as expected. Additional issues are observed and studied as they impact the San Diego trolley and roadway operation. Identified issues are summarized and recommendations provided to further improve the system performance. An additional FOT is recommended to confirm findings and resolve newly identified issues in use of the adaptive signal priority system design. The recommendations cover six aspects: signal transition, signal progression, dwelling time prediction, arrival time prediction at stations, integration of priority decision with prediction, and the automatic vehicle location (AVL) system.

Although many different railroad grade crossing control products are available, the most challenging limitation to traditional grade crossing systems is their inability to deliver consistent warning times in response to varying train speeds and station stops (particularly nearside stops). As a result, rail-roadway crossings often generate conflicts and congestion for motorist traffic and sometimes delay trains.

Challenges and Advances in Sustainable Transportation Systems, 2014

A number of injuries and fatal collisions have occurred at certain highway-rail grade crossings that are located immediately adjacent to highway intersections, driveways or interstate ramps. Some guide signage, pavement markings, and other traffic control devices present near or at the crossings in the past may have confused drivers and caused them to turn onto the railroad tracks, rather than at the nearby intersections, driveways or ramps. This research found the major contributing causes of incorrect turns onto railroad tracks includes (1) confusing signs and pavement markings near highway-rail crossings, (2) darkness and low visibility near or at highway-rail crossings, (3) following turn instructions from a GPS device onto railroad tracks, (4) skewed highway-rail grade crossings, and (5) driver distraction. Based on the findings from intensive literature review, historical crash data analysis, and field observations, a set of practical countermeasures was developed to prevent incorrect turns onto railroad tracks. The major recommended treatments for upstream of a highway-rail grade crossing include advance direction signage and striping. The recommended downstream treatments also consist of guide signs and striping. For the critical zone, treatments such as striping or dynamic envelope pavement markings, pavement gate markings, bollards, and illumination are recommended. Adequate illumination is essential for reducing the number of rail-vehicle crashes and stuck vehicle incidents due to incorrect turns at night. Finally, this research developed a simple and effective method to help quantify potential drivers that experience confusion or hesitation when they approach a highway-rail grade crossing. It provided a cost-effective method to evaluate the effectiveness of any implemented treatments to prevent incorrect turns onto railroad tracks.

2013

A number of injuries and fatal collisions have occurred at certain highway-rail grade crossings that are located immediately adjacent to highway intersections, driveways or interstate ramps. Some guide signage, pavement markings, and other traffic control devices present near or at the crossings in the past may have confused drivers and caused them to turn onto the railroad tracks, rather than at the nearby intersections, driveways or ramps. This research found the major contributing causes of incorrect turns onto railroad tracks includes (1) confusing signs and pavement markings near highway-rail crossings, (2) darkness and low visibility near or at highway-rail crossings, (3) following turn instructions from a GPS device onto railroad tracks, (4) skewed highway-rail grade crossings, and (5) driver distraction. Based on the findings from intensive literature review, historical crash data analysis, and field observations, a set of practical countermeasures was developed to prevent incorrect turns onto railroad tracks. The major recommended treatments for upstream of a highway-rail grade crossing include advance direction signage and striping. The recommended downstream treatments also consist of guide signs and striping. For the critical zone, treatments such as striping or dynamic envelope pavement markings, pavement gate markings, bollards, and illumination are recommended. Adequate illumination is essential for reducing the number of rail-vehicle crashes and stuck vehicle incidents due to incorrect turns at night. Finally, this research developed a simple and effective method to help quantify potential drivers that experience confusion or hesitation when they approach a highway-rail grade crossing. It provided a cost-effective method to evaluate the effectiveness of any implemented treatments to prevent incorrect turns onto railroad tracks.

Journal of Safety Research, 1988

The work investigated each level grade crossing along Iddo-Alagbado rail corridor of Lagos State of Nigeria, and prescribed improvements in bringing about safety. ECF and USDOT accident prediction models were used to evaluate the level crossing considered. Also, guidelines for highway-rail crossing improvement according to MUTCD were used to determine the adequate improvement needed at the level crossings. The major finding of this paper is that a majority of the at-grade rail crossings need some improvements to be in compliance with MUTCD standards. From the results obtained, two at-grade crossings were identified for additional traffic control devices or consolidation of TCDs while the third at-grade crossing was identified for grade separation, and/or additional traffic control devices beyond MUTCD standards.

Journal of transportation engineering, 2007

Flexible traffic separator systems, widely used to alert motorists to lane restrictions, have been suggested as relatively inexpensive, easily maintainable countermeasures to discourage motorists from driving around the gates at highway-railroad grade crossings. A flexible traffic separator system was installed and evaluated at three crossings in central Florida using a before and after study. The effectiveness of the separators was determined by the number of vehicles driving around the gates, compared with the number of vehicles having a chance to do so. The effect was significant, in that a total of 25 out of 2,194 vehicles drove around the gates before the separator installation, whereas only one out of 1,246 vehicles was involved in this type of violation after the treatment. The presence of the traffic separators was not shown to have a significant effect on crossing actions of approaching motorists when the gates were descending. There was, however, some evidence that drivers were more inclined to enter the crossing when the gates were ascending after the train passage.