Each year in April, National Work Zone Awareness Week is held to bring national attention to motorist and worker safety and mobility issues in work zones. Since 1999, the Federal Highway Administration (FHWA) has worked with the American Association of State Highway and Transportation Officials (AASHTO) and the American Traffic Safety Services Association to coordinate and sponsor the event. This year’s theme is “Work Zone Safety: We’re All In This Together.”

Researchers at the Texas A&M Transportation Institute (TTI) are dedicated to improving motorist safety, worker safety and traveler mobility in all types of highway work zones. “Each year in Texas, there are approximately 15,000 crashes and more than 100 people killed in highway construction and maintenance zones,” says TTI Work Zone and Dynamic Signs Program Manager Jerry Ullman. “Among the leading causes are excessive speed and the failure to remain alert while driving.”

According to the Texas Department of Transportation (TxDOT), Texas has seen a decline in work zone fatalities for two consecutive years because of increased safety measures and public outreach efforts.  While work zone fatalities and crashes have declined significantly, there is still work to do.

• Four out of every five work zone fatalities are motorists traveling through the work zone.
• Forty-five percent of all work zone fatalities for 2010 were 35 years old or younger.
• In 2010, 61 percent of work zone fatalities were male.
• Of the 100 work zone fatalities in 2010, 54 were drug and alcohol-related.

Texas motorists encounter a large number of work zones in place across the state.  One prime example of these types of efforts is the massive rebuilding effort of 90 miles of Interstate 35 through the TxDOT Waco District in central Texas.  TTI researchers are working closely with TxDOT and contractors in developing ways to maximize safety and mobility within this corridor during reconstruction.

TTI also maintains the National Work Zone Safety Information Clearinghouse, which is the largest online resource for roadway construction safety. The clearinghouse is a joint effort of the American Road and Transportation Builders Association, FHWA and TTI.

Visitors to the National Work Zone Safety Information Clearinghouse website “are expected to find a wealth of information related to work zone safety including crash data, expert contacts, laws and regulations, safety standards, agency practices, news articles, research publications, training courses, videos, and safety products,” says TTI Research Librarian Hong Yu, who maintains the website. “If they do not find what they need on our website, they can also contact us for a customized research service or post a question on our clearinghouse listserv.”

Since the site went online in 1998, the clearinghouse has assisted more than 1.3 million users from every state and 33 countries with a variety of topics related to safety issues in work zones.

“Certainly the decreased in work zone fatalities is encouraging,” says Ullman. “We have all come together to make a real difference in continuing to make work zones safer.”

Safety in work zones is no different. The biggest threat to work-zone safety occurs when motorists and workers come into conflict — when a car strays into a work-zone area, for example, putting all involved at risk.

Of course, the safest solution is to always use positive protection to separate motorists and workers while work is ongoing. But that’s not always possible in today’s economic environment. Cash-strapped states have to optimize how resources are spent on their transportation networks.

Though the Texas Department of Transportation (TxDOT) has had procedures in place for assessing the need for positive protection for years, those guidelines relied on specific assumptions about where intrusions might occur. The agency decided it needed more comprehensive guidelines, so a team led by Jerry Ullman, manager of the Texas A&M Transportation Institute’s Work Zone and Dynamic Message Sign Program, conducted a project to develop the needed guidelines.

“I feel that our real contribution in this project lies in generalizing the potential location of the worker or equipment throughout a given work-zone area,” says Ullman. “This makes our model more realistic and, therefore, more accurate when applied to real-world situations.”

Researchers looked at the number of vehicles traveling in a corridor to estimate the probability that a motorist-worker conflict would occur. Using those data, Ullman and his team compared the cost of installing and maintaining traffic barriers with the societal costs associated with injuries and deaths resulting from crashes. From there, they came up with specific break-even recommendations for when Texas should introduce positive protection to work zones.

Put simply, the study showed that the closer the work area is to the travel lanes, the more justified positive protection is. That’s because there’s a higher probability, with a closer proximity of motorist to worker, for conflict to occur. As the distance between the travel lanes and the work-zone area increases, the cost benefit of installing protective barriers decreases at lower volumes.

Researchers also found that steel and mobile barriers can be cost-effective alternatives for short-duration mobile operations with workers on foot in high-volume, high-speed corridors. Truck-mounted attenuators were also found to be very cost effective, offsetting their costs in less than a year of use in most cases.

“Through this project, the researchers were able to determine when and under what conditions barrier protection is justified,” says Research Engineer Wade Odell of TxDOT’s Office of Research and Technology Implementation. “This is significant in that the contractor can provide motorists with proper protection in a work zone and still provide the protection cost effectively.”

This Issue

Partners in Transportation Research

Volume 48, Number 3
September 2012
Issue Overview

On this page:

• For More Information

“Positive protection” refers to the addition of equipment (e.g., traffic barriers) to the work-zone environment to minimize or prevent motorist-worker conflict.

For more information:

Jerry Ullman
(979) 845-9908
j-ullman@tamu.edu

]]> http://tti.tamu.edu/2012/09/01/providing-positive-protection-for-work-zones/feed/ 0 http://tti.tamu.edu/2011/09/01/tti-studies-increased-crash-rates-along-the-dfw-connector/ http://tti.tamu.edu/2011/09/01/tti-studies-increased-crash-rates-along-the-dfw-connector/#comments Thu, 01 Sep 2011 14:35:16 +0000 Tobey http://tti.tamu.edu/?p=6873 Take a dynamic work zone that can change daily. Add distracted drivers. What do you get? That’s what the Texas Department of Transportation wanted to know. Jason Crawford, manager of the Texas Transportation Institute’s North Texas Region, began looking for answers.

What he and his team of researchers discovered is that more drivers are turning their attention away from driving while passing through a construction zone. The roadway in question is a $1 billion project known as the DFW Connector, which skirts the northwest side of the Dallas/Fort Worth International Airport. Over 200,000 motorists pass through it daily.

TTI researchers were asked to evaluate the work zone because of higher-than-normal crashes, especially at night and on weekends. A statistical review separated injury crashes from non-injury crashes. That analysis showed that injury crashes occurred less frequently than the national work zone average, while property damage crashes happened more often.

Researchers concluded that the higher night and weekend crash numbers were the result of driver distraction, since drivers failed to notice traffic flow changes resulting from lane and total freeway closures. Crawford notes, “There can’t be any lane closures during the day. All of the work that happens above traffic lanes or impacts highway lanes occurs overnight or on the weekends.”

Crawford describes the construction area as “one where you have a lot of merging traffic. You also have a lot of weaving traffic. There are temporary lane shifts the contractor has in place. If you’re not really paying attention and the lane shifts, you could sideswipe someone.”

Cell phones may be adding to the complexity of navigating the work zone. Average cell use while driving in the Dallas/Fort Worth area is 6 percent, according to National Highway Traffic Safety Administration estimates. TTI researchers noted 12 percent usage in the DFW Connector work zone. Researchers feel that cell phone use could be a contributing factor to increased property damage crashes, although data did not allow them to make a causal link.

“We’re trying to get drivers to slow down and pay attention. The landscape for that construction project can change almost on a daily basis as you’re going through. There are crashes. And, the rate of cell phone usage is twice what you’d normally see,” Crawford says.

The study determined that drivers do not accurately perceive the safety risks involved with distracted driving in a complex construction zone like the DFW Connector.

The contractor has already acted on the findings. “Since we came out with the cell phone study, the contractor has implemented a number of coordinated campaigns, through banners and bumper stickers,” says Crawford. “The campaigns encourage drivers to slow down and pay attention.” The banners state, “Please don’t text and drive. My Daddy Works Here,” and “Let us work safely. Drive 50 mph!”

“They’re trying to increase awareness, not only for their guys, but also for the motoring public,” Crawford explains.

The study also recommends changes to lane-shift locations and markings, lighting practices and site maintenance to make the DFW Connector the safest work zone possible.

This Issue

Safety Is No Laughing Matter

Volume 47, Number 3
September 2011
Issue Overview

On this page:

• For More Information

For more information:

Jason Crawford
(817) 462-0534
jcrawford@tamu.edu

]]> http://tti.tamu.edu/2011/09/01/tti-studies-increased-crash-rates-along-the-dfw-connector/feed/ 0 http://tti.tamu.edu/2010/12/01/tti-in-the-media/ http://tti.tamu.edu/2010/12/01/tti-in-the-media/#comments Wed, 01 Dec 2010 15:58:23 +0000 Chris Sasser http://tti.tamu.edu/?p=1009 Over the past year, TTI experts answered tough questions on a variety of state and national transportation issues. Over 2,500 newspaper articles, broadcast television spots and professional journals — with a potential reach of over 725 million readers and viewers nationwide — mentioned the Institute or its experts. Here are a few excerpts of TTI‘s media coverage over the last fiscal year.

For more information, please contact Rick Davenport at (979) 862-3763 or r-davenport@tamu.edu.

The Wall Street Journal

Sept. 10, 2010, “Deaths in crashes decline amid gains in car safety”

“The focus on engineering and enforcement has taken us to this point,” said Quinn Brackett, a safety researcher with the Texas Transportation Institute. Now, he added, “We need to focus on a paradigm shift away from occupant protection toward crash avoidance.”

Austin-American Statesman

June 13, 2010, “Going, going, going, going green: Impact is multiplied when entire fleets embrace alternative fuels, improved efficiency”

“Due to economic competition and the perpetual drive to reduce operating costs, freight shippers and carriers already have significant incentive to minimize fuel costs and thereby (greenhouse gas) emissions, which are second only to labor costs and increasingly volatile,” said Annie Protopapas, an associate research scientist with the Texas Transportation Institute at Texas A&M University. “In the long term, they do realize substantial cost savings.”

Reader’s Digest

Oct. 1, 2009, “Unlocking gridlock”

“We can’t get rid of traffic, but we can shorten commutes by operating our roads better ‘ clearing wrecks faster and timing lights more efficiently.”

Tim Lomax,
Texas Transportation Institute

Kansas City Star

Aug. 14, 2010, “Wrecks point up work-zone risks”

About a third of all work-zone crashes in Missouri can be attributed to inattentive driving, and the second-leading contributing factor is following too closely. Both were cited in last week’s bus crash. … “It’s one of the very reasons that it’s hard to guard work zones against serious crashes,” said Gerald Ullman, senior research engineer at the Texas Transportation Institute. “We can put up all the signs we want, and all the bells and whistles,” Ullman said. “What we can’t control is did they see it. That’s why we’re so concerned about distracted driving in work zones.”

The Washington Post

Feb. 7, 2010, “Racking up miles? Maybe not.”

Within a few years, a driver who pulls up to the gas pump may pay two bills with a single swipe of the credit card: one for the gas and the other for each mile driven since the last fill-up. … But getting the public and its elected officials to accept that idea maybe a tough sell. …

“Technology is not the limiter,” said Ginger Goodin, a senior research engineer at the Texas Transportation Institute who did a major study on pricing. “The decision is in the policy arena. It’s entirely up to lawmakers and their constituents.”

The Arizona Republic

Aug. 19, 2010, “HAWK lights to help reduce pedestrian deaths in metro Phoenix”

The Texas Transportation Institute has done two studies of the HAWK (High Intensity Activated Crosswalk) system and found they work. Last year, the institute studied Tucson HAWK lights and found there were 69 percent fewer accidents involving pedestrians and 29 percent fewer crashes overall at the HAWK sites, said Kay Fitzpatrick, a senior research engineer with the institute.

This Issue

Working Across Transportation Solutions

Volume 46, Number 4
December 2010
Issue Overview

On this page:

• The Wall Street Journal
• Austin-American Statesman
• Reader’s Digest
• Kansas City Star
• The Washington Post
• The Arizona Republic

For more information:

Rick Davenport
(979) 862-3763
r-davenport@tamu.edu

]]> http://tti.tamu.edu/2010/12/01/tti-in-the-media/feed/ 0 http://tti.tamu.edu/2010/09/01/the-forgiving-roadside-tti-research-facilities-are-vital-to-protecting-your-loved-ones/ http://tti.tamu.edu/2010/09/01/the-forgiving-roadside-tti-research-facilities-are-vital-to-protecting-your-loved-ones/#comments Wed, 01 Sep 2010 20:56:43 +0000 Chris Sasser http://tti.tamu.edu/?p=1281

Cable barriers installed on a stretch of IH 20 in Texas. Cable barriers have proven very cost effective in reducing head-on collisions across traffic lanes while slowing down vehicles with minimal impact on their occupants.

It’s five times safer to travel on our nation’s roadways today than it was five decades ago. For every 100 million miles Americans traveled in 1960, five people died. Today, the rate has dropped to just over one death per 100 million miles.

“As a nation 50 years ago, we decided that killing tens of thousands of people a year was unacceptable,” says Roger Bligh, manager of Texas Transportation Institute’s (TTI) Roadside Safety Program. “That’s why the concept of the `forgiving roadside’ was developed.”

In the 1960s, TTI led the safety movement on the new Interstate Highway System by conducting crash tests on signs, guardrails and crash cushions at its Proving Ground Research Facility, the Institute’s crown jewel for improving roadside safety.

TTI‘s technological innovations can now be seen on virtually every mile of roadway in Texas. Since TTI researchers created the earliest versions of the slip-base breakaway signs in the 1960s, more than 2,000 crash tests have been conducted at the Proving Ground, which recently gained accreditation by the American Association for Laboratory Accreditation for “technical competence in the field of mechanical testing.” Today, the facility also includes the Center for Transportation Computational Mechanics, where analysts run computer simulations to evaluate potential roadside safety solutions before performing the actual crash.

Perhaps TTI‘s most recognizable contribution to the forgiving roadside is the ET2000® guardrail end treatment. Developed in 1991, over half a million units have been installed throughout the United States and around the world. The ET2000® absorbs energy from a crash by deflecting the guardrail away from the impacting vehicle.

Recently, TTI helped develop and crash-test more forgiving median barriers made of cables rather than concrete. Concrete barriers continue to serve an important role in separating traffic on urban highways with narrow medians, but cable barriers have proven very cost effective in reducing head-on collisions across traffic lanes while slowing down vehicles with minimal impact on their occupants. The result has been a dramatic decrease in cross-median collision fatalities where cable median barriers have been implemented in the United States.

“Passenger vehicles can hit the cable, and most of the time they just drive off,” explains Marla Jasek, director of transportation operations for the Texas Department of Transportation Yoakum District.

But the forgiving roadside doesn’t maintain itself. Crews work to improve and repair roadways while drivers speed by, creating danger for both workers and drivers. An estimated 1,000 people are killed and 45,000 are injured in United States roadway work zones each year.

Portable concrete barriers are an integral part of the work-zone safety equation, shielding motorists and protecting workers. TTI continues to develop new barrier alternatives that offer designers safe and effective solutions for restricted work-zone sites. The new X-bolt connection reduces the deflection of free-standing barriers to less than 2 feet, and a drop-pin anchorage system permits portable concrete barriers to be installed along the edge of a bridge deck.

TTI research in work-zone safety includes its award-winning National Work Zone Safety Information Clearinghouse.

TTI is also promoting work-zone safety through its award-winning National Work Zone Safety Information Clearinghouse (http://www.workzonesafety.org), the world’s largest Internet resource on all things related to work-zone safety. The clearinghouse is a project of the American Road and Transportation Builders Association and is operated in cooperation with the U.S. Federal Highway Administration and TTI. Since the site went online in 1998, it has assisted half a million users from every state and 27 countries with a variety of topics related to safety issues in work zones.

“We have all come together to make a real difference in making work zones safer,” says Jerry Ullman, manager of TTI‘s Work Zone and Dynamic Message Signs Program.

Commentary on Safety

by Mary McDonough
Roadway Departure Program Manager
Federal Highway Administration

“Roadway departure” refers to vehicles crossing a center or edge line or otherwise leaving a roadway. Crashes from roadway departure account for over half of U.S. fatalities. Causes of leaving the roadway include use of alcohol and cell phones, speeding and distracted driving. Some die from these crashes. Many more suffer incapacitating, lifelong injuries. They and those who know them are profoundly changed by these events.

What most people don’t realize is that the deadliest place to drive isn’t a busy freeway or a high-speed interstate. It’s a two-lane rural road. Horizontal curves, pavement drop-offs, narrow lanes, and trees and poles next to the roadway — all pose serious dangers on these roads.

Roadside safety countermeasures have dramatically improved in recent decades. Guardrail end treatments, breakaway signs, cable median barriers and other technological innovations keep millions safe when they depart the roadway. And more safety measures to reduce crashes and their severity are being developed.

The Federal Highway Administration’s policy and guidance includes performance testing for roadside hardware devices before they’re installed. Formal acceptance of crashworthy devices is our responsibility, and external partners with the highest standards of quality, such as the researchers at the Texas Transportation Institute (TTI) Proving Ground, greatly assist us in that mission. TTI has helped raise the bar of excellence for other researchers. The Institute’s consistently reliable, proactive approach to device testing has helped save thousands of lives, not only in Texas but across the nation.

Our greatest hope is that you never use the safety features installed on roadways. No matter how well we do our jobs, the best way to avoid injury is for you, the individual, to be a consciously competent driver (and passenger). So stay safe, stay alert, and be cautious, especially on two-lane roads. Ultimately, safety is the responsibility of each and every one of us.

This Issue

Solving the Transportation Puzzle

Volume 46, Number 3
September 2010
Issue Overview

On this page:

• Commentary on Safety
• For More Information

“As a nation 50 years ago, we decided that killing tens of thousands of people a year was unacceptable. That’s why the concept of the ‘forgiving roadside’ was developed.”Roger Bligh, manager of TTI’s Roadside Safety Program

But the forgiving roadside doesn’t maintain itself. Crews work to improve and repair roadways while drivers speed by, creating danger for both workers and drivers. An estimated 1,000 people are killed and 45,000 are injured in U.S. roadway work zones each year.

For more information:

Gene Buth
(979) 845-6159
g-buth@tamu.edu

]]> http://tti.tamu.edu/2010/09/01/the-forgiving-roadside-tti-research-facilities-are-vital-to-protecting-your-loved-ones/feed/ 0 http://tti.tamu.edu/2010/03/01/work-zone-up-ahead-other-states-call-tti-for-work-zone-research/ http://tti.tamu.edu/2010/03/01/work-zone-up-ahead-other-states-call-tti-for-work-zone-research/#comments Mon, 01 Mar 2010 18:59:45 +0000 Chris Sasser http://tti.tamu.edu/?p=1534

A mobile arrow panel alerts motorists to an upcoming lane merge.

Traffic operations, such as improving the safety and efficiency of work zones, are coast-to-coast priorities. Texas Transportation Institute (TTI) researchers journey outside the Lone Star State whenever — and wherever — duty calls. Three recent work zone projects have been part of TTI‘s effort to help sponsors nationwide.

Intrusion Countermeasures

Orange-and-white drums do not always prevent motorists from veering into a highway work zone area. These dangerous driving situations, called intrusions, caught the attention of the California Department of Transportation (Caltrans). So when Caltrans decided to evaluate strategies and devices other than barriers to reduce intrusions, TTI‘s Jerry Ullman took the wheel.

“The common belief is that all intrusions are caused by the driver losing control and veering into the work zone,” says Jerry Ullman, senior research engineer. “But the research shows a lot of intrusion problems are the result of deliberate driver disregard for traffic control.”

Jerry Ullman’s team researched the chain of events that lead to intrusions and brainstormed countermeasures that could be used to alter those chains, such as closer spacing of drums, placing barricades crosswise more frequently in closed lanes, and providing law enforcement presence upstream and within the work zone. The project, now in its final stages, will provide guidance for which countermeasures should be used under certain roadway conditions and the cost-effectiveness of each.

Improving Road Restriping Safety

One emerging technology for work zones and incident traffic control is the truck-mounted changeable message sign (TMCMS). These signs provide drivers with information on upcoming problems and actions to take. They are smaller than typical changeable message signs and have less character space and character height but are mobile.

A few states, such as Wyoming and Texas, have begun using TMCMSs, but there is limited research on how to establish effective messages for the smaller-format signs during active work operations. The Wyoming Department of Transportation (WYDOT) wanted to use TMCMSs for striping projects but needed guidance on applicable situations and appropriate messages. So WYDOT teamed up with TTI‘s Brooke Ullman, an expert on changeable message signs.

“The key is not to overload drivers. Drivers have limited time to read, comprehend and react to TMCMS messages. The message must be concise but get the point across,” says Brooke Ullman, assistant research engineer. “TMCMSs are great technology when used effectively.”

Brooke Ullman’s team surveyed WYDOT field personnel to identify the main hazards associated with mobile operations and potential ways the TMCMS could be used to help mitigate those hazards. After assessing driver reaction to several of the more promising messages, the researchers recommended TMCMS message sets for mobile operations for WYDOT to consider.

“Mike Gostovich, state traffic engineer for WYDOT (now retired), told me he is amazed with the depth and usefulness of the information provided by TTI in the report. Mike asked me to send copies of the report to each of our transportation districts, and each district is now budgeting funds to purchase at least one, and perhaps more, truck-mounted changeable message signs,” says Michael Patritch, research manager at WYDOT. “From project completion to implementation, the results of the study can be measured in mere days.”

Utility Operations Merging Taper Length

A utility crew performing maintenance on a streetlight requires a temporary work zone.

Conditions such as lighting, sight distance, traffic volume and speed all factor into the effectiveness and risk associated with temporary traffic control for utility work. Research on merging taper lengths — the practice of using cones to slowly merge two lanes of traffic into one — has been very limited.

Utility companies in Florida, in order to follow federal guidelines on merging taper lengths, sometimes spend 30 minutes to set up cones to spend 5 minutes changing a lightbulb. This time inefficiency led the Florida Department of Transportation (FDOT) to call TTI for research on using shorter merging taper lengths for short work duration activities, while also minimizing risk to the worker and motorist.

“As engineers, we can’t lose sight of the fact that we have to balance both the workers’ safety and the safety of the motoring public. We can’t leave the worker exposed without visual cues for the motorist, but on the other hand, we could endanger the motorist by leaving something in the lane,” says LuAnn Theiss, an associate research engineer with TTI.

Theiss’s team recommends that operations that last more than 15 minutes should utilize merging taper lengths that meet federal requirements. However, for utility crew operations lasting 15 minutes or less, the large bucket truck and flashing lights appear to provide sufficient cues to drivers.

“We were very glad to have the TTI team do this research for us,” says Jim Mills, a roadway design engineer with FDOT. “It was much-needed research that hasn’t been addressed anywhere. More research is needed, but it certainly provided us with information that will be used to improve our work zone standards.”

This Issue

Improving Our Transportation Operations

Volume 46, Number 1
March 2010
Issue Overview