Tennessee Fights Roadway Departure Crashes

Transcription

1 Vol. 29/No. 1/Spring 2015 Tennessee Fights Roadway Departure Crashes by Matt Cate, P.E. The Federal Highway Administration (FHWA) defines a roadway departure crash as one in which a vehicle crosses an edge line or a center line, or otherwise leaves the traveled way. If this sounds like a broad definition, it is. Roadway departure (RD) crashes encompass a variety of crash scenarios, including collisions between vehicles traveling in opposite directions on the same roadway, vehicles striking terrain and drainage features, and collisions with fixed objects such as trees and utility poles. These crashes represent a significant percentage of highway fatalities in the United States. With this in mind, a number of resources have been committed to the fight against RD. This article will highlight these resources at both the national and state levels and discuss several events and resources available through TTAP to help you combat RD crashes in your local community. State and National Statistics Nationally, RD was involved in 51% of the nation s 29,867 fatal crashes in Among these RD fatal crashes, 24% involved a vehicle leaving the right side of the roadway, 17% involved a vehicle crossing the roadway centerline or median, and 10% involved a vehicle leaving the left side of the roadway. Many of these crashes involve a collision with a fixed object adjacent to the roadway. Nationally, In this issue... trees and traffic barriers combine to account for almost half of all fatal crashes where collision with a fixed object is listed as the first harmful event. In Tennessee, RD is involved in an even-higher percentage of fatal crashes. In 2013, 623 of 995 roadway fatalities (63%) resulted from RD. Trees, ditches, and embankments accounted for more than half of the state s fixed object fatalities in The impact of RD crashes becomes even more evident when examining trends in serious injury crashes. While lane departure deaths have declined slightly since 2008, serious injuries resulting from lane departure crashes have increased from 2,480 in 2008 to 3,146 in 2012 (an increase of almost 27%). Strategies to Prevent Roadway Departure Crashes In an effort to reduce the rate and overall occurrence of fatalities and injuries on our nation s roads, FHWA developed its Focused Tennessee Fights Roadway Departure Crashes... 1 From the Director... 2 HFST Demonstration Event Planned in September... 5 And the Winter has left us... 6 continued on page 3 1

2 RoadTalk is a publication of the Tennessee Transportation Assistance Program (TTAP). TTAP is part of a nationwide Local Technical Assistance Program (LTAP) financed jointly by the Federal Highway Administration (FHWA) and Tennessee Department of Transportation (TDOT). The views, opinions, and recommendations contained within this newsletter are those of the authors and do not necessarily reflect the views of FHWA and TDOT / ROAD ctr.utk.edu/ttap Dr. David B. Clarke, P.E, Director (dbclarke@utk.edu). Frank Brewer, Training Coordinator (fbrewer1@utk.edu) Matt Cate, P.E, Technical Assistance Coordinator (mcate@utk.edu) Dr. Airton G. Kohls, Engineer (akohls@utk.edu) Daniel Herman, Technician (dherman2@utk.edu) Spence Meyers, Database,Website & Technical Assistance (meyers@utk.edu) Jenny Jones, RoadTalk Editor (gohjones@utk.edu) Mollie Mitchell, Administrative Specialist (mmitche6@utk.edu) Diana Webb, Course Registration (dwebb21@utk.edu) The University of Tennessee does not discriminate on the basis of race, sex, color, religion, national origin, age, disability, or veteran status in provision of education programs and services or employment opportunities and benefits. This policy extends to both employment by and admission to the University. The University does not discriminate on the basis of race, sex, or disability in the education programs and activities pursuant to the requirements of Title VI of the Civil Rights Act of 1964, Title IX of the Education Amendments of 1972, Section 504 of the Rehabilitation Act of 1973, and the Americans with Disabilities Act (ADA) of Inquiries and charges of violation concerning Title VI, Title IX, Section 504, ADA, the Age Discrimination in Employment Act (ADEA), or any of the other above referenced policies should be directed to the Office of Equity and Diversity; 1840 Melrose Avenue; Knoxville, TN ; telephone (865) (TTY available). Requests for accommodation of a disability should be directed to the ADA Coordinator at the Office of Human Resources Management; 600 Henley Street; Knoxville, TN PA# R From the Director As I write this, April showers are hard at work, hopefully bringing May flowers. I know they re making my grass grow! It s obviously been a rough winter, judging from the craters I m dodging on my travels around the state. I can t recall seeing this many potholes since the late 1970s. A lot of them seem to be the result of overlays de-bonding and breaking away. Our pavements definitely have a lot of problems that need to be addressed during this year s maintenance season! There s been a lot of pavement distress research conducted over the years. Given the magnitude of the pothole problem, we haven t gotten enough solutions into practice. With that said, I d like to make you aware of several new TTAP initiatives that are now in the early stages of development. First, TTAP will partner with TDOT and FHWA to develop and conduct demonstrations of innovative products and technologies. TTAP has always supported FHWA s Every Day Counts initiatives, which highlight innovations. During 2014, TTAP sponsored a demonstration of the Safety Edge pavement treatment. We think such demonstrations are an important and highly effective means of technology transfer. If new practices aren t publicized, implementation will be slow at best. Our next demonstration, now being scheduled, will showcase High-Friction Surface Treatments (HFST). HFSTs can be applied at relatively-low costs using hand tools, dramatically increasing surface friction at locations including curves and intersection approaches where wet-weather crashes are common. Please let us know if you have suggestions for a product demonstration. We ll seriously consider them. Our second planned initiative is development of a series of technical materials that will highlight common topics of interest or importance to Tennessee s local roadway agencies. The TTAP produced Work Zone flipbook has been extremely popular over the years. We plan for the new guides to draw from numerous sources and place the information in a concise, easy-to-understand format. They will incorporate Tennessee-specific regulations, policies, and examples. Where appropriate, guides will highlight techniques and practices suited to our conditions. Thinking outside the box, we are seriously considering the use of YouTube and/or apps suitable for tablets and smartphones as distribution media, rather than being limited to print format. These have some exciting possibilities, as most of you are aware. At any rate, stay tuned. We would love to hear suggestions from you about what you need and what formats would be most useful. That s it for now. As always, if we can help, please don t hesitate to call or . TTAP looks forward to assisting you. Stay cool! 2

3 Tennessee Fights Roadway Departure Crashes, continued from page 1 Approach to Safety. As a part of this program, FHWA has made RD one of three emphasis areas for which states may receive additional technical assistance, training, and data analysis. Tennessee is currently a RD focus state. FHWA also developed a Roadway Departure Strategic Plan (2013) to help guide its own activities and interactions with state DOTs. This 2013 plan establishes overturning crashes, opposite direction crashes, and roadside tree and shrub crashes as its primary points of emphasis. FHWA has also supported the development and implementation of a number of countermeasures against RD. Included among these strategies are: pavement-related improvements such as the Safety Edge, high friction surface treatments, and rumble strips and stripes; increased nighttime visibility via retroreflective traffic signs and pavement markings horizontal curve safety through improved delineation FWHA has included several of these treatments on its list of Proven Safety Countermeasures. Longitudinal rumble strips and stripes on two-lane roads, enhanced delineation and friction for horizontal curves, and the Safety Edge are RD countermeasures included on the current list. Finally, FHWA is emphasizing systemic safety improvements as a way to proactively address a number of highway safety concerns, including RD. The systemic approach to safety allows state and local agencies to proactively apply safety treatments across the transportation network by assessing risk rather than reactively providing improvements after crashes occur. This flexibility is especially important given the seemingly random nature of many RD crashes. The Tennessee Department of Transportation (TDOT) has also taken steps to address RD crashes on our state s roadways. The 2014 Tennessee Strategic Highway Safety Plan (SHSP) features RD prominently in its Infrastructure Improvements Emphasis Area Plan. In the period from 2008 to 2012, RD-related fatalities and serious injuries (44.5%) were by far the most prevalent crash type by infrastructure category, well ahead of intersections (26.1%), railroad crossings (0.1%), and other (29.2%). The 2014 SHSP identifies several strategies to decrease the occurrence and severity of RD crashes over the next five years, including: the use of road safety audits development and implementation of a Roadway Departure Action Plan o centerline, edge line and shoulder rumble strips and stripes o signs (including advisory speed plates) and pavement markings o reflectorized snowplowable pavement markers o alignment and object delineation o cable barrier installation o asphalt pavement safety edge installation the use of high-friction surface treatments implementation of a shoulder-widening program continuation of TDOT s Local Roads Safety Initiative (LRSI) The plan also designates TTAP as an outlet for training and information specific to the Infrastructure Improvements Emphasis Area. By including these emphasis areas and countermeasures in the SHSP, TDOT can use Highway Safety Improvement Program (HSIP) funds to implement improvements at locations where crash data or systemic risk analysis indicate a higher than average likelihood of crashes. How Can TTAP Help You Address Roadway Departure Crashes? As Tennessee s Local Technical Assistance Program (LTAP) center, one of TTAP s primary tasks is to provide training, technology transfer, and technical assistance resources that help local agencies to improve roadway safety. We want to take this opportunity to highlight several of these resources and to preview an upcoming event that will showcase one of the key RD countermeasures. Training TTAP s training program includes a number of workshop titles that address roadway departure continued on page 4 3

4 Tennessee Fights Roadway Departure Crashes, continued from page 3 crashes by providing information on safety data analysis and countermeasures, roadway maintenance and design, and traffic operations. Each of these classes addresses one or more elements of the roadway that may affect the probability of RD crashes. Included in this list are: Highway Safety Analysis (June 2, Knoxville) Road Safety 365: Everyday Safety for Local and Rural Roads (July 7, Nashville) Roadside Safety Standards (August 4, Nashville) Traffic Signs and Pavement Markings Road Safety Audits Traffic Sign Retroreflectivity Geometric Design for 2-Lane Roads and Streets Drainage System Maintenance Fundamentals of Traffic Control Dates and locations are shown for classes scheduled in the remainder of Many of the other workshops will be offered again in All training titles are available upon request - please contact Frank Brewer, TTAP Training Coordinator, for additional information regarding this process. Technical Assistance TTAP provides free technical assistance to any local agency in Tennessee. The scope of this assistance can range from a single phone call or to one or more on-site visits depending on the type and complexity of the issue being evaluated. TTAP s staff includes three engineers who are available to help you address a specific concern or condition at a real-world location. TTAP s technical assistance efforts typically focus on providing lowcost safety improvements such as signs, markings, and delineators to address safety issues. TTAP s technical assistance program also incorporates an equipment loan program, including access to a Safety Edge show made available through FHWA (see sidebar). To learn more about TTAP s technical assistance program, visit our website at or contact Matt Cate at mcate@utk.edu. Safety Edge Shoe Available for Use by Tennessee Local Agencies If you attended the August 2014 Safety Edge Open House and Demonstration event co-hosted by TTAP, FHWA, and TDOT, you are already familiar with the basics of the Safety Edge, its benefits, and the equipment required to create it during paving projects. If not, please visit the TTAP website ( ttap/safety.php) to see pictures, video, and materials from the event held in Nashville. You may also wish to visit FHWA s Safety Edge website ( gov/everydaycounts/technology/safetyedge/intro.cfm) to see research reports, national crash statistics, case studies, and more. Whether or not you attended the event in Nashville, TTAP has a Trans Tech Shoulder Wedge Maker ( available for use by any Tennessee city or county agency who wants to use the safety edge on new construction or resurfacing projects. To learn more about this opportunity or to request use of the device, please contact Matt Cate at or mcate@utk.edu. 4 continued on page 5

5 Tennessee Fights Roadway Departure Crashes, continued from page 4 Technology Transfer Technology transfer, or T2, is the third and final area in which TTAP provides support to Tennessee s local transportation agencies. Our T2 program includes the RoadTalk newsletter, video and publication libraries, the TTAP website, and special events such as the August 2014 Safety Edge Open House and Demonstration. We constantly strive to bring you information on new safety technology and resources, as well as focusing on the tried and true techniques that any agency can use to improve safety on its roadways. As Dr. Clarke mentions in his From the Director column, TTAP will increase its focus on special events and reference materials that have been developed or customized for our in-state audience of local officials. The next of these T2 events will be a High Friction Surface Treatments (HFST) Open House and Demonstration to be held in Nashville in September. Watch the TTAP website, your inbox, and future issues of RoadTalk for more information on these special events and publications. Roadway Departure Resources on the Web FHWA Roadway Departure website: dot.gov/roadway_dept/ 2014 Tennessee Strategic Highway Safety Plan: docs/shsp pdf FHWA Roadway Departure Countermeasures: safety.fhwa.dot.gov/ roadway_dept/rdctrm.cfm NHTSA Fatality Analysis Reporting System website: HFST Demonstration Event Planned in September The High Friction Surface Treatments Open House and Demonstration will provide an opportunity for Tennessee s highway superintendents, public works directors, engineers, and other transportation officials to learn more about the benefits of HFST in reducing the occurrence of crashes at horizontal curves, intersections, and other locations where surface friction is critical. This event will be held in Nashville with a preliminary target date in the early part of September. This event is a partnership between the Tennessee Department of Transportation (TDOT), the FHWA Tennessee Division, and TTAP. The primary goal of the HFST demonstration is to raise awareness of High Friction Surface Treatments among Tennessee s local agency staff members and decision makers. Through discussions with participants, we also hope to identify any existing obstacles that may prevent or reduce the opportunities for local agencies to use HFST. The event will include discussion of the benefits, costs, application, and maintenance of HFST, a firsthand look at a finished HFST installation, and a demonstration of tools and materials used to apply the surface treatment. Watch the TTAP website and your inbox for additional details as the event agenda and date are finalized in the coming months. 5

6 And the Winter has left us.. Source: Airton Kohls and NCHRP 463 Pavement Patching Practices The 2015 Winter left behind plenty of headaches to our transportation system in TN. As TTAP traveled around the State we were able to experience firsthand what was left of our roads after all the sleet, ice and snow. It was amazing to see all the tree damage in the Cumberland Plateau as well as navigating through the series of potholes in West TN. In the last Roadtalk we had an article on debris management and for the current newsletter my focus will be on pointing you to resources on pothole patching. Appropriately, NCHRP (National Cooperative Highway Research Program) has just released Synthesis 463 on Pavement Patching Practices. Despite advances in material selection and pavement design, pavement distresses and failures still occur (Figure 1). When they do so, on a small scale, or in fairly isolated locations patching is the most common maintenance technique used to restore pavement functionality. While actual figures are difficult to obtain, it is safe to assume that well over $1 billion is spent each year to maintain roadways in the United States. In 1999, it was estimated that more than $1 billion was spent annually in the United States on pothole and costs have increased since then. With such a large expenditure of tax dollars, it is important to ensure that the funds are spent in a cost effective manner and that the investments in patching result in improved pavement performance and longer service lives. NCHRP 463 presents the current state of the practice regarding pavement patching practices and updates the information available on patching practices to enable agencies to make informed decisions about their own patching policies and procedures. It is intended Figure 1. Continuous pavement deterioration due to poor initial patching practices. (R. McDaniel) to document the state of the practice for patching relatively small-scale defects or distresses in both asphalt and concrete pavements. Large-scale patches, wedge and level (or level-up patching), and pre-overlay patching are not the focus. In particular, the document examines the following: Current programs for repair and patching; Pavement distress factors that identify a good candidate for repair and patching; Performance information under different conditions such as season, time available, and traffic; Repair and patching materials and associated performance for both asphalt and concrete pavements; Review of public and private repair and patching specifications, including quality measurement practices such as smoothness and density control for asphalt patching and opening strength for concrete patches; 6 continued on page 7

7 And the Winter has left us..., continued from page 6 Repair and patching design and construction practices for manual and automated repairs; Traffic control requirements and practices for pavement repair and patching; Repair and patching equipment, including types of automated equipment; Methodology to track and report on patches, such as Global Positioning System (GPS) and geographic information system (GIS) mapping tools and maintenance management condition assessment systems or processes; Unit cost information; and Ongoing research and future needs. The main focus of this document is on reactive, manually installed patches over relatively small areas; however, some information was also gathered on planned and machine fabricated patches. The focus is also on patching that is intended to serve traffic for some time, whether temporarily or permanently, and does not include patches placed immediately before placement of an overlay. Distresses Suitable for Repair by Patching For the most part, the definitions of the distress terms used herein correspond to those in the Distress Identification Manual for the Long-Term Performance Program DIM - ( gov/publications/research/infrastructure/pavements/ ltpp/reports/03031/03031.pdf). Many states use this manual and therefore are familiar with the terminology. In asphalt pavements, the most common distresses that can be repaired by patching include potholes, deterioration around cracks, delaminations, rutting, or raveling. The DIM does not include deterioration around a crack as a distress, but does include high severity cracking, which could describe this type of deterioration. In this document, the term delamination refers to the separation of one layer of an asphalt pavement from the underlying layer; some refer to this as peeling. In the DIM, this would be categorized as a pothole. One distinguishing feature of a delamination versus a pothole is that a delamination has a flat bottom at the top of the underlying layer, whereas a pothole is bowl-shaped. Figures 2 and 3 illustrate potholes and delaminations, respectively. To learn about the latest information on patch preparation, patch material, placement methods and much more please go to onlinepubs/nchrp/nchrp_syn_463.pdf and download NCHRP 463 Pavement Patching Practices. Figure 2 Potholes caused by poor drainage (Source: Cornell Local Roads Program, CLRP). Figure 3 Delamination of surface layer (Source: CLRP). 7

8 Tennessee Transportation Assistance Program Center for Transportation Research The University of Tennessee 309 Conference Center Building Knoxville, TN Ph. (865) /(800) 252-ROAD Fax. (865) Web. Non-Profit Org. U.S. Postage PAID Permit No.481 Knoxville, TN TALK TO TTAP We are always looking for your comments, ideas and suggestions to help make the TTAP Program more useful to you. Please fill out and fax the form below to TTAP at (865) or mail to TTAP; Suite 309 Conference Center Building, Knoxville, TN Please send me more information on the following articles mentioned in this newsletter. 2. Please list any additional training workshops you would be interested in attending. 3. Please list topics for videos you would like TTAP to obtain. 4. Please list any other ideas or suggestions on how TTAP could assist you. 5. Please list your name and organization to verify for TTAP s mailing list. Name Address Title Organization Phone Fax Are you currently on TTAP s mailing list? yes no Do you wish to be on the mailing list? yes no 8