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19 CHAPTER THREE APPLICATIONS OF IN-PAVEMENT MARKER TECHNOLOGY This chapter details experiences from recent IPM system Some issues related to water penetration and subsequent elec- applications, including documentation of system and facility trical failures were reported with this system. Also, a recent characteristics, operation modes, installation and construc- ice storm required contractors to "blade" the streets, resulting tion methods, maintenance requirements, system costs, and in the accidental removal of the IPM system markers. perceived and measured effectiveness. Applications are categorized by their function: to warn, guide, regulate, or Costs for the original system, installed before the provide illumination for road users. Table 3 lists novel IPM 20002001 school year, totaled $38,000. The city of Edmond system applications, identified primarily through the trans- budgets $55,000 each year for school zone improvements, portation practitioner survey and the IPM system vendor which now include IPM systems, as well as signalized count- survey. down pedestrian crossings and real-time, radar-based driver feedback speed signs (T. Minnick, personal communication, Aug. 8, 2007). WARNING To measure the effectiveness of the IPM system in enhanc- With the primary intent to warn road users, IPM systems have ing school zone safety, vehicle speed data were collected been implemented--as an isolated system or in combination before the system was installed and seven months after the with other warning devices--in school zones, in construction activation of the system. The incidence of speeding in the zones, at highwayrail crossings, along horizontal curves, school zone was approximately 30% before the installation and in areas that experience frequent adverse weather. of the IPM system and dropped to 19% after the installation. Additionally, a survey was conducted to determine how par- ents, police, teachers, and bus and daycare van drivers reacted School Zones to the IPM system. The survey showed that 95% of the re- spondents had noticed the IPM system, 93% believed the As a natural outgrowth of pedestrian crosswalk applications, IPM system increases awareness of the school zone, and 89% IPM systems have recently been implemented to provide believed the system improves safety in the school zone supplemental warning in school zones. (Speeding . . . 2002). Risner Elementary School, Edmond, Oklahoma Construction Zones In 2000, the city of Edmond, Oklahoma, installed an IPM Various Locations--Iowa, Kansas, Missouri, system at the Orvis Risner Elementary School to augment and Nebraska flashing school zone beacons that are activated during spe- cific periods in the morning and afternoon. Yellow IPM sys- In 1999, a collaborative study of smart work-zone technology tem markers are placed along the double yellow centerline was performed by the State Departments of Transportation in through the school zone (see Figure 5). The first installation Iowa, Kansas, Missouri, and Nebraska (the Midwest Smart had the markers spaced at a distance of 50 ft; subsequent in- Work Zone Deployment Initiative) (Meyer 2000b). One of stallations have reduced the marker spacing to 25 ft. the technologies tested during the deployment initiative was an IPM system. The IPM system is activated 30 min before, and deacti- vated 10 min after, classes begin in the morning. In the after- During the deployment, the westbound lanes of I-70 in noon, the system is activated 10 min before, and deactivated Kansas were closed and two-way traffic was redirected to the 30 min after classes end. The system operates in constant two eastbound lanes, approximately 10 miles east of Salinas, flash mode when activated. Kansas. An IPM system was used to delineate the general traffic lanes and the crossover traffic lanes from the west- Because the times of operation are only during daylight bound side of I-70. The IPM system markers were installed hours, the city had engaged the system vendor to enhance the using a "temporary" asphalt adhesive at a distance of 50 ft luminous intensity of the markers in daylight conditions. apart for approximately 1,200 ft (M. Harrison, personal

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20 TABLE 3 SUMMARY OF NOVEL TECHNOLOGY APPLICATIONS Application Source Warning School zones Orvis Risner Elementary School; Edmond, Oklahoma Vendor survey Construction zones Various Locations; Kansas, Nebraska, Iowa, and Missouri Vendor survey Highway-rail Paramount Boulevard at Rosecrans Avenue; Paramount, Vendor survey crossings California Horizontal curves Interstate 95 at State Road 84; Fort Lauderdale, Florida Vendor survey I-126 at Greystone Boulevard; Columbia, South Carolina Transportation practitioner survey FM 127; Mount Pleasant, Texas Vendor survey US 59 at Loop 151 Flyover; Texarkana, Texas Vendor survey N200 between Overveen and Bloemendaa; Province of Noord- Vendor survey Holland, the Netherlands A4226 (Five Mile Lane); Vale of Glamorgan, Wales, United Vendor survey Kingdom Adverse weather I-526, Cooper River Bridge; Charleston, South Carolina Vendor survey Various Locations; Virginia Vendor survey Guidance Multiple-turn lanes SH 99 at Arch Road, Single-Point Urban Interchange; Stockton, Transportation California practitioner survey Wabash Avenue at Veterans Parkway; Springfield, Illinois. Vendor survey Merge locations Route 46; Totoda Burrow, Wayne Township, New Jersey Vendor survey Tunnels McClure Tunnel; Santa Monica, California Vendor survey Wilson Tunnel, Route 63 (Likelike Highway); Honolulu, Hawaii Transportation practitioner survey Tunnel #1, SR 20 between Newhalem and Diablo; Washington Internal leads Regulation Intersection stop Disneyland Drive near Disneyland Resort; Anaheim, California Vendor survey Bars 2nd Street at Adams Street; Coquille, Oregon Vendor survey West Alabama Street at the Galleria; Houston, Texas Vendor survey Various Locations along METRORail Line; Houston, Texas Internal leads Left-turn Various Locations along METRORail Line; Houston, Texas Internal leads restrictions Illumination Vehicle/truck Vandenberg Air Force Base; Santa Barbara County, California Vendor survey inspection points Environmentally SR A1A, Boca Raton, Florida Vendor survey sensitive areas N513 Highway; Castricum, Province of Noord-Holland, the Vendor survey Netherlands communication, July 2007). Amber lights were used to de- In addition to the IPM system, a safety warning system lineate the left edge, placed just beyond the edgeline, and (SWS) was deployed before activation of the IPM system. The white lights were used to delineate the right edge, also placed SWS warned drivers of the work zone through a recorded just beyond the edgeline. The lights operated in a steady-burn message transmitted from a radar signal to select radar mode (Meyer 2000a, b). detectors and other in-vehicle receivers. The evaluation was intended to determine if the use of the IPM systems, in combination with SWS, reduced speeds and improved lane-keeping in the work zone. Vehicle speeds through the work zone were collected: (1) before the imple- mentation of either system, (2) after the activation of the SWS, and (3) after the activation of the IPM system (in simultane- ous operation with the SWS). Following activation of the IPM system, a statistically significant decrease in the mean and 85th percentile speeds was observed. A nighttime speed reduction of more than 6 mph was recorded for both passenger cars and trucks. Additionally, a 7% decrease was noted for drivers exceed- FIGURE 5 School zone IPM system application in Edmond, ing the posted speed limit (29% to 22%). Researchers noted Oklahoma (Courtesy: SmartStud Systems). that the devices that were the most effective based on the

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21 quantitative data collected were the speed display and the hardwired (as compared with solar) IPM system (Meyer 2000a). Lane-keeping is also important in a construction zone be- cause it helps prevent lane crossovers and subsequent head- Rosecrans Avenue Railroad Crossing on collisions. The lane-keeping benefit of the IPM system was measured using pneumatic tubes placed partially in the Paramount Boulevard roadway. The tubes were configured in such a way to track whether a vehicle encroached on the centerline or right line by three feet, two feet, or one foot. If a vehicle did not activate any of these tubes, it was assumed that the vehicle was trav- eling in the middle of the designated lane. The percentage of vehicles within one foot of the inside edge decreased from 8.9% to 5.2%, indicating that vehicles were traveling closer to the middle of the lane while in the construction zone (Meyer 2000a). This reduction proved to be statistically FIGURE 6 Paramount Boulevard at Rosecrans Avenue, significant. Paramount, California. One challenge to IPM system use in construction zones is When the train approaches, it must receive a green indica- the ability to supply and route adequate power cables. The tion on the tracks before proceeding through the intersection. use of solar-powered IPM systems was investigated in this When the train has a green indication, all vehicle traffic ap- same study. Unlike the hardwired systems, the solar-powered proaches receive a red indication and the IPM markers begin IPM systems did not produce statistically significant results flashing with a red illumination. Typically, all rail activity because the lighting was reportedly too dim (E. Meyer, per- occurs during daylight hours; the illuminated markers appear sonal communication, July 26, 2007). bright enough for all approaches. Few operational issues were reported with the system HighwayRail Crossings based on four years of operation. Only one instance of an electrical short circuit was reported; 66 of the markers tem- Paramount Boulevard at Rosecrans Avenue, porarily lost power. Occasional power washing by city street Paramount, California crews is required for the system (B. Pagett, personal com- munication, July 23, 2007). The highwayrail crossing at the intersection of Paramount Boulevard and Rosecrans Avenue in Paramount, California, For this application, the IPM system was originally ap- is atypical because the railroad crosses diagonally across the proved by the California Public Utilities Commission and intersection and not just across one approach. The intersection FHWA as a demonstration project. The system cost between was too wide for regular railroad crossing gates and the typ- $55,000 and $60,000. ical railroad crossing lights would have visually blocked the existing traffic signal faces. Sight distance issues were caused by a building on one corner. An IPM system was identified as a suitable alternative warning device at this location (see Figures 6 and 7). Eighty-five red LED IPM system markers were used in the application. More markers were required here than at an intersection with a 90 degree railroad crossing because the markers must be seen from all four approaches. The rail line is a spur trap that services a refinery, with trains crossing once or twice per day (i.e., a daily delivery in and out). The trains do not travel at high speeds, but rather at approximately 5 mph. Traffic volumes at the intersection are high; approximately 30,000 vehicles per day eastbound and westbound and 20,000 vehicles per day northbound and southbound. Additionally, there are approximately 400 high FIGURE 7 At-grade highwayrail crossing IPM system school and middle school students who walk through this in- application, Paramount, California (Courtesy: LightGuard tersection each day. Systems, Inc.).

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22 No formal evaluation of IPM system effectiveness has been performed. Anecdotally, the Paramount city engineer noted that no crashes have occurred at the intersection since the in- stallation (predeployment crash data were not available) and that the school crossing guards have reacted positively to the system. Horizontal Curves In-pavement marker systems offer the potential for increased visibility over traditional RRPMs through horizontal curves. RRPMs function by reflecting light from a vehicle's head- lights. Hence, the entire extent of some horizontal curves cannot be illuminated by RRPMs. On the other hand, IPM markers can be designed to provide illumination from a wider range of viewing angles; giving a more consistent, complete, and clear indication of road curvature. A number of horizon- tal curve IPM system applications were identified. FIGURE 9 Horizontal curve IPM system application, Interstate 95 at State Road 84, Fort Lauderdale, Florida (Courtesy: Florida Department Fort Lauderdale, Florida of Transportation). In November 2004, the Florida Department of Transportation speed. As the driver slows, the chase sequence slows. The IPM (FDOT) installed an IPM system on the exit ramp from south- system markers extend through the entrance to SR 84 to pro- bound I-95 to westbound State Road (SR) 84. The intersec- vide added warning of the curvature at this location (G. Soles, tion has been the site of several crashes attributable to high personal communication, July 26, 2007). vehicle exit speeds from I-95 and the sharp, 90 degree turn required for traffic to enter onto SR 84 (see Figures 8 and 9). The IPM system at this location has experienced a num- ber of setbacks to effective operation. Lightning strikes, The IPM system is activated when a vehicle is detected maintenance crew familiarity with the IPM system, power traveling at 45 mph or greater on the I-95 exit ramp. The IPM supply issues, and pavement resurfacing activity have pre- system operates in a reverse chase sequence (i.e., toward the vented continuous successful operation for periods longer vehicle), giving a driver the sense that he is traveling at a faster than six months. The IPM system was struck by lightning twice within a two-month period, motivating the vendor to install addi- tional grounding for the system. Next, a maintenance crew, unfamiliar with the power supply system, reconnected the power supply incorrectly to a night timer causing the lights to function only at night. The lights were restored to 24-h function, but another storm caused an electrical malfunction in the system. The system was repaired and upgraded with addressable chips by the vendor; FDOT reported significant improvement in system performance after the installation of addressable chips. The IPM system was also compromised during recent Exit Ramp to road resurfacing activities. The contractor was provided a SR 84 map and verbal direction where the IPM system loops, lights, and wiring were installed, but the system was still acciden- tally damaged by the contractor's milling machine. In this in- stance, the system was very hard to repair because the milling damage to the cabling was under the surface and difficult to detect. After the system was restored following resurfacing, FIGURE 8 Exit ramp from I-95 to SR 84, Fort Lauderdale, another lighting strike hit. The system was restored but, in Florida. July 2007, was again reported as being without power.

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23 Unfortunately, no automatic feedback system is available to provide information regarding system failure or real-time status. Malfunctions are often reported to FDOT by the Florida Highway Patrol and Road Ranger motorist assistance program drivers. Despite the technical issues that the system has incurred, FDOT believes the system is very effective and important for enhancing safety on the exit ramp. According to FDOT, the IPM system markers are very sturdy and are capable of being driven over by semi-trucks with no apparent damage. FDOT has also received positive feedback from the public regard- ing the system. Once IPM system operation has stabilized (i.e., successfully operating continuously for at least six FIGURE 11 Horizontal curve IPM system application (daylight), months), FDOT will formally evaluate its effectiveness. Data Mount Pleasant, Texas (Courtesy: TxDOT Atlanta District). reflecting conditions before IPM system installation have been previously collected for comparison. Each marker cost approximately $55, with a total of 13 units installed ($715) and installation was performed by South I-126 at Greystone Boulevard, Columbia, Carolina DOT (SCDOT) personnel. The IPM system is likely South Carolina too new (installed one month ago at the time of this report) to report any operational or maintenance related issues or to At the exit ramp to Greystone Boulevard from I-126 near provide substantive perceptions of effectiveness. Personnel Columbia, South Carolina, road users were observed travers- from SCDOT did indicate that 2 of the 13 chevron signs on the ing a horizontal curve with excess speed, leading to frequent curve have been hit by vehicles since the recent installation of run-off-the-road crashes into traffic control devices intended the IPM system. No information was provided regarding the to warn the driver (e.g., chevron signing along the curve). An frequency of crashes prior to IPM system installation for com- IPM system was implemented at this location to increase the parison (A. Leaphart, personal communication, July 2007). visibility of the curve (see Figure 10). For a distance of 200 ft, IPM system markers were at- Farm-to-Market 127, Mount Pleasant, Texas tached directly to the surface of the roadway using butyl The Texas DOT (TxDOT) had a problematic horizontal curve pads. The markers consist of two LEDs for illumination, on Farm-to-Market (FM) 127 outside of Mount Pleasant, but also provide passive guidance through a reflector- Texas. The curve is in a rural area with no safety lighting; road ized lens (similar to an RRPM). The IPM system is solar- users were frequently leaving the road and running into traffic powered; each marker is activated internally by a photocell control devices intended to warn the driver (e.g., chevron and operates during low-light times. Once activated, the signing along the curve). To enhance curve delineation, IPM units flash at a rate of approximately 60 to 80 times per system markers were mounted on the chevron sign posts (a hole minute. was drilled in the chevron's pipe and the marker was bolted to the post using antitheft bolts) (see Figures 11 and 12). FIGURE 10 I-126 at Greystone Boulevard, Columbia, FIGURE 12 Horizontal curve IPM system application (night), South Carolina. Mount Pleasant, Texas (Courtesy: TxDOT Atlanta District).

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24 The original IPM system that was installed at this location was solar-powered. The observed luminous intensity was often less than desired owing to large trees in the area that were preventing the solar panels from receiving enough light to adequately charge the system. To remedy these issues, in 2006, the IPM system was modified and hardwired to an AC power source. Luminous intensity has appeared to improve following this modifica- tion; TxDOT personnel noted that during night operation the markers are "super bright," but can still be seen reasonably well during the day, because of the shadows cast from sur- rounding trees. The IPM system operates 24 hours per day and is activated FIGURE 13 Horizontal curve IPM system application (close-up when an upstream radar detector, located on an advance view), Texarkana, Texas (Courtesy: TxDOT Atlanta District). warning sign, detects a vehicle traveling faster than the posted advisory speed of 35 mph. When the system is acti- vated, the lights operate on a steady burn until the ambient vated, the IPM system markers on the chevron sign posts light is bright enough to turn off the photocell. flash with the advisory speed beacons. The IPM system at this location has experienced some The installation and equipment cost approximately $15,000 challenges since implementation, but TxDOT is working for this application. Personnel from TxDOT remarked that with the manufacturer to remedy issues with the system. One that the system is not a low-cost solution, but is applicable to challenge with this installation was the physical length the most critical problematic locations (C. Ibarra, personal (one-half mile) and the power requirements of each marker. communication, Aug. 3, 2007). Each marker requires 21 volts to operate, and ensuring enough voltage is available to illuminate the last sets of markers Other than the issues identified previously related to along the line was difficult because of power consumption power source (hardwired versus solar), no issues related to along the cable. In response, the manufacturer developed spe- installation, operation, or maintenance were reported for this cial power reduction modules that adjust the initial 33-volt system. A few incidents of vandalism (e.g., markers stolen) input to the required 21 volts per marker. At the end of the have occurred. half-mile installation, no additional power reduction is nec- essary to achieve the required 21-volt power. Personnel from Overall, TxDOT personnel assess the IPM system posi- TxDOT suggested that this installation would have been tively, but note that familiar road users do not reduce speeds easier if a power supply had been provided at each end of for the curve because the locals know how to traverse the the line. The IPM system cost $56,000 for an approximate curve. Operational impacts for unfamiliar motorists may be half-mile length of roadway, which included equipment and most important. No formal evaluation has been performed to installation. determine the effectiveness of the IPM system in improving safety at this site. U.S. 59 at Loop 151 Flyover, Texarkana, Texas After the TxDOT Atlanta District experienced perceived success with the IPM system application on FM 127, an ad- ditional candidate location was identified. The flyover from U.S. 59 onto Loop 151 in Texarkana, Texas, had a long his- tory of road users impacting the ramp barriers. This flyover ramp is also in a fog-prone area. For this installation, IPM system markers were installed on the right-side concrete barrier of the curve (see Figures 13 and 14). The installation is approximately one-half mile long. The markers were bolted directly to the barrier using antitheft bolts. The IPM system is activated by a photocell and is illuminated FIGURE 14 Horizontal curve IPM system application, when the ambient light begins to dim. Once the system is acti- Texarkana, Texas (Courtesy: TxDOT Atlanta District).

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25 A4226 (Five Mile Lane), Vale of Glamorgan, Wales, United Kingdom Five Mile Lane--a narrow rural roadway--is characterized by a high degree of curvature. In response to an elevated crash rate, several mitigating treatments were implemented including a speed limit reduction, deployment of mobile and permanent speed cameras, supplemental road markings and signage, and pavement resurfacing with high-skid-resistance material. In July 2002, an IPM system was installed to en- hance delineation on the centerline of this two-lane roadway (see Figure 17). It was noted that in the three years after the IPM system FIGURE 15 Horizontal curve IPM system application (aesthetic was installed, crash rates were reduced by 72% when com- view), Texarkana, Texas (Courtesy: TxDOT Atlanta District). pared with the three years prior to installation. It was believed that the increased visibility in the curved sections contributed to the reduction in crashes (Astucia Traffic Safety Systems A formal evaluation of the effectiveness of this IPM system 2007c). has not been done. Anecdotally, TxDOT personnel report fewer tire marks on the barriers at this location than before. Additionally, TxDOT personnel believe that the markers add Adverse Weather to the aesthetics of the flyover (see Figure 15) (C. Ibarra, per- sonal communication, Aug. 3, 2007). The effectiveness of IPM systems in enhancing safety and operations during adverse weather conditions has been the subject of international and domestic study. N200 between Overveen and Bloemendaa, Province of Noord-Holland, the Netherlands In a laboratory setting in Australia, Styles (2004a) consid- ered the activation performance of environmentally triggered Limited information was available regarding an IPM sys- IPM systems. Thirteen light-sensitive, five temperature- tem implemented in the Province of Noord-Holland along sensitive, and seven moisture-sensitive markers were tested N200 in the Netherlands. N200 is a four-lane, divided according to their response to fading light, fog, and low tem- roadway characterized by a high degree of curvature. IPM perature. Based on these tests, it was noted that the markers system markers are installed on the outside edge of each will perform their intended illuminating tasks: (1) before ice curve (see Figure 16). The benefits of this system are formation, (2) upon formation of moisture on their surface, purported to be increased safety and an energy reduction and (3) in advance of light intensity levels falling below levels of more than 90% when compared with conventional that are present with good street lighting. overhead illumination (Astucia Traffic Safety Systems 2007b). FIGURE 16 Horizontal curve IPM system application, Province of Noord-Holland, the Netherlands (Courtesy: Astucia Traffic FIGURE 17 Horizontal curve IPM system application, Wales, Safety Systems). United Kingdom (Courtesy: Astucia Traffic Safety Systems).