Universities Join Forces to Test Resiliency of Bridge Design

In a study published in the Journal of Structural Engineering, Texas A&M University and the University of Colorado-Boulder researchers have conducted a comprehensive damage and repair assessment of a still-to-be-implemented bridge design using a panel of experts from academia and industry. The researchers said the expert feedback method offers a “unique and robust” technique for evaluating the feasibility of bridge designs that are still at an early research and development phase.

[Photo courtesy of Texas A&M University.]

“Bridges, particularly those in high-seismic regions, are vulnerable to damage and will need repairs at some point,” explained Dr. Petros Sideris, assistant professor in Texas A&M’s Zachry Department of Civil and Environmental Engineering, in a blog post.

“Now the question is what kind of repairs should be used for different types and levels of damage, what will be the cost of these repairs and how long will the repairs take — these are all unknowns for new bridge designs,” he added. “We have answered these questions for a novel bridge design using an approach that is seldomly used in structural engineering.”

Most bridges are monolithic systems made of concrete poured over forms that give the bridges their shape: a design strong enough to support their own weight and other loads, such as vehicle traffic. However, Sideris said if there is an unexpected occurrence of seismic activity, such structures could crack and remedying that damage would be exorbitantly expensive.

To overcome such shortcomings, Sideris and his team – with funding from the National Science Foundation – developed a new design called a hybrid sliding-rocking bridge. Instead of a monolithic design, these “sliding rocking” bridges are made of columns containing limb-inspired joints and segments. Hence, in the event of an earthquake, the joints allow some of the energy from the ground motion to diffuse while the segments move slightly, sliding over one another rather than bending or cracking.

Yet despite potential benefits of this design, no data existed about how it would behave in real-world situations. That is where the new testing procedure developed by Texas A&M and the University of Colorado-Boulder comes into play.

“To find the correct repair strategy, we need to know what the damages look like,” Sideris said. “Our bridge design is relatively new and so there is little scientific literature that we could refer to. And so, we took an unconventional approach to fill our gap in knowledge by recruiting a panel of experts in bridge damage and repair.”

Sideris, Dr. Abbie Liel at the University of Colorado-Boulder, and their respective research teams recruited a panel of eight experts from industry and academia to determine the damage states in experimentally tested hybrid sliding-rocking segment designed columns. Based on their evaluations of the observed damage, the panel provided repair strategies and estimated costs for repair.

The researchers then used that information to fix the broken columns, retested the columns under the same initial damage-causing conditions and compared the repaired column’s behavior to that of the original column through computational investigations.

The panel found that columns built with their design sustained less damage overall compared to bridges built with conventional designs. In fact, the columns showed very little damage even when subject to motions reminiscent of a powerful once-in-a-few-thousand-years earthquake. Furthermore, the damage could be repaired relatively quickly with grout and carbon fibers, suggesting that no special strategy was required for restoration. “Fixing bridges is a slow process and costs a significant amount of money, which then indirectly affects the community,” explained Sideris. “Novel bridge designs that may have a bigger initial cost for construction can be more beneficial in the long run because they are sturdier. The money saved can then be used for helping the community rather than repairing infrastructure.”

After Bush Fire, Arizona DOT Pivots to Address Extreme Weather

When combined with fire-ravaged terrain, heavy rain creates a whole new set of highway maintenance issues.

[Above photo courtesy of Arizona DOT.]

Take California, for starters. Already in the midst of fighting several major wildfires, the state is already gearing up for potentially damaging weather/terrain scenarios that can develop due to post-fire conditions.

The California Department of Transportation dealt with one such situation three years ago when a mudslide covered portions of U.S. 50 following several heavy and wet winter storms.

In Arizona, the infamous Bush Fire in June – a human-triggered inferno that burned more than 193,000 acres of desert and vegetation in Tonto National Forest near the northeast suburbs or Phoenix ― left behind dry, rocky terrain that could not handle the rushing waters of a monsoon, since the fire melted away vital ground cover.

Thus the need arose to craft a faster response effort to address those specific conditions. As a result, the Arizona Department of Transportation created an emergency action plan that dispatches specialized highway crews that can deal with the impact that heavy rain causes on fire-scorched terrain.

Photo courtesy of Arizona DOT

Part of the good news, explained Kevin Duby, statewide road weather manager for the agency, is that the Arizona DOT created this response plan at minimal cost plan by piggybacking off an initiative of the Federal Highway Administration’s Pathfinder Program. An offshoot of the Every Day Counts innovation recognition initiative, the Pathfinder Program, keeps travelers informed, and improves safety, mobility and the movement of goods during storms via enhanced collaboration between federal, state, and local agencies.

“We utilized previous plans obtained by research on the topic, which resulted in better use of time and cost savings for taxpayers,” said Duby.

With the help of the National Weather Service or NWS, the Arizona DOT identified “areas of the watershed where problems could arise and cleaned out the drainage ditches,” Duby emphasized, noting that no major construction was necessary because cleared culverts were already in place.

“They can accommodate the water in the normal flow from the steep slopes of the Mazatzal Mountains,” he said; a range known locally as the Four Peak Mountains.

Duby added that the Arizona DOT “already had a great relationship” with NWS via several groups from within the agency, from regional districts to operations to public relations.

The depth of those collaborations proved more advantageous and timelier than originally imagined.

“The plan was completed on July 28,” Duby said. “Then about a week later we had a mudslide on State Route 188,” which connects the towns of Globe and Payson, near Roosevelt Lake, which had been identified as a flood problem area.

“We worked with NWS to come up with protocols when a storm was imminent,” Duby noted. “One was for the NWS to call our traffic operations center,” to warn representatives of the impact of the rain.

At that juncture, the traffic operations center and public information offices broadcast the information on social media. Once the flooding occurred, the Arizona DOT executed its plan and was able to respond quickly with heavy equipment in a pre-staging area. That included vehicles such as loaders, skid-steers, and backhoes; as well as barriers and portable message boards. The agency also identified alternate highway routes – notably State Route 87 and U.S. 60.

Photo courtesy of Arizona DOT

“Part of the initiative is to be proactive about getting messages out to the travelling public, with the best information we can offer,” Duby pointed out.

While he said there is also an estimated cost savings aside from avoiding the commuter delays due to the Arizona DOT’s approach, it also helped alleviate the environmental issues that are part of any major weather event.

Without the efforts of the parties involved, “taking care of that sudden real world event would have been more complicated,” explained Duby. “We had to be sure that all three Arizona DOT districts are in sync, because they all have separates staffs,” adding that Phoenix and Flagstaff – about two hours away – both have NWS offices, so keen communication between the two proved critical.

Today, the focus is on taking what’s been learned from the Bush Fire and the mudslide and use that information to prepare for the next potential weather disaster. “We’ve refined our approach and that’s making traveling safer for our citizens,” Duby emphasized.

ETAP Podcast: Hawaii DOT’s Ed Sniffen

In this episode of the Environmental Technical Assistance Program or ETAP podcast, host Bernie Wagenblast interviews Ed Sniffen (seen above), deputy director for highways at the Hawaii Department of Transportation, regarding how his agency is focused on improving infrastructure resilience.

Sniffen also serves as the chair of the Committee on Transportation System Security and Resilience for the American Association of State Highway and Transportation Officials. The mission of the TSSR committee is to coordinate national response efforts, identifies best practices, and fills research gaps to promote resilient and secure transportation systems across the country. To listen to the podcast, click here.

State DOTs on the Front Lines of Storm Preparations

State department of transportation crews along the Gulf Coast prepared for the arrival of two potentially dangerous storms this week – highlighting the key ways state DOTs protect critical infrastructure and the residents it serves during severe weather events.

[Above photo courtesy of Louisiana DOTD.]

Crews in Texas, Louisiana, and Mississippi cleared storm drains and ditches, lowered light masts, paused highway construction projects and pre-positioned barricades, signs, and portable dams to prepare for the impact of hurricanes Marco and Laura – even as forecasts for the intensity and paths those storms changed almost hourly.

“Hurricanes are part of living here,” explained Sarah Dupre, a public information officer with the Texas Department of Transportation.

“We’re treating it just like one big storm,” added Rodney Mallet, communications director for the Louisiana Department of Transportation and Development.

Photo courtesy of Louisiana DOTD

Part of Louisiana’s preparations means removing tolls on the Louisiana Highway 1 Bridge to accommodate a mandatory evacuation of Grand Isle, the state’s only inhabited barrier island. The Louisiana DOTD also pre-positioned dozens of school buses and motor coaches in other vulnerable areas throughout south Louisiana to aid with potential evacuations.

By Sunday, Mississippi Department of Transportation crews had removed computerized traffic light controllers from major intersections south of Interstate 10 and set the traffic signals to all-flash mode, noted Katey Roh, a public information officer with the agency. That action protects the controllers from floodwaters, while the controllers “flash mode” helps move potential evacuation traffic better than allowing the signals to run on regular cycles.

Although Mississippi does not have a contraflow plan – a situation in which vehicles travelling on a main road in one direction must use lanes normally used by traffic travelling in the opposite direction – it works closely with Louisiana DOTD’s contraflow plan. That plan uses all northbound and southbound traffic lanes on Interstate 55 and Interstate 59 to evacuate the greater New Orleans area into central and north Mississippi. As of Tuesday morning, neither Louisiana nor Texas had implemented a contraflow plan.

“Contraflow is a last resort,” explained TxDOT’s Dupre. “Right now, our crews are preparing for evacuations, and we have dispatched courtesy patrols to help motorists.”

Those three state DOTs also stressed that personnel and equipment must be pre-staged in relatively safe locations to respond to the most vulnerable, low-lying areas in the wake of a storm’s passage. “The most important thing is to make sure our resources are in the right places,” Mississippi DOT’s Roh said. “We’ve been through a number of storms like this, and we know which areas tend to flood, so our first responders are ready to go.”

Caltrans Issues Final Two of 12 Climate Change Vulnerability Reports

The California Department of Transportation recently finalized and issued the last two of 12 district-based Climate Change Vulnerability Assessment Reports; studies designed to create a “comprehensive database” to help Caltrans evaluate, mitigate, and adapt to the effects of extreme weather events on the state transportation system.

[Above photo courtesy of Caltrans.]

“The completed assessments cover all 58 counties in the state and give California a comprehensive evaluation of climate change effects on the State Highway system,” explained Toks Omishakin, director of Caltrans, in a statement. “We are now integrating the findings into our planning process to better protect California’s citizens, economy and transportation investments.”

The final two reports cover Caltrans coastal district 1 and coastal district 5 and examine the potential impact of rising average temperatures, higher sea levels, storm surge, and precipitation on California’s transportation system – climate change trends that the agency said, in turn, increase incidences of flooding, drought, wildfires, coastal erosion and mudslides.

Caltrans said that understanding the impact of climate change helps the agency assess physical climate risk to the transportation system and work towards adapting infrastructure to be more “resilient” to those impacts. For example, the agency’s 12 climate reports project that by the year 2085:

  • Sea levels will rise 5.5 feet along the California coast—affecting 130 miles of State Highway by accelerating soil erosion and cliff retreat.
  • Increased severity and frequency of wildfires could threaten more than 7,000 miles of state highway.
  • High temperatures on the central coast and in the northwest part of the state could rise by 6 to 12 degrees, increasing drought and wildfire potential.

Caltrans began publishing those climate change reports in December 2018 partly in response to Executive Order B-30-15 issued by outgoing Gov. Edmund G. Brown Jr. (D), which mandated the integration of climate change analysis into transportation investment decisions.

FEMA Issues COVID-19/Hurricane Response Guidance

The Federal Emergency Management Agency has issued a 59-page document that provides Federal, state, local, tribal, and territorial or SLTT officials – along with those of private sector and non-governmental organizations (NGO) – guidance on how to respond to both the COVID-19 pandemic and hurricanes simultaneously.

“As SLTT partners continue to prepare for hurricane season and other emergent incidents, emergency managers should review and adjust existing plans – including continuity of operations (COOP) plans – to account for the realities and risks of COVID-19 in their prioritization of life-saving and life-sustaining efforts,” FEMA said in the document.” All reviews and adjustments to plans should factor-in FEMA’s planned operational posture, social distancing measures, CDC [Centers for Disease Control] guidance, and SLTT public health guidance.”

To ensure that operational decisions are made at the lowest level possible, FEMA is organizing to prioritize resources and adjudicate accordingly, if needed:

  • At the incident level, Federal Coordinating Officers (FCO – in consultation with regional Administrators – will work to address incident requirements using available resources. FCOs will proactively manage and identify risks and communicate new requirements to Regional Response Coordination Center or RRCCs as they arise.
  • At the regional level, the RRCCs will coordinate with FEMA personnel deployed to SLTT emergency operation centers and adjudicate resource requests until operational control is ready to be transitioned to the FCO at the incident level, when designated, and will adjudicate resources within their area of operation and coordinate with other RRCCs and the National Response Coordination Center (NRCC) as required.
  • At the national level, the NRCC will coordinate with the regions on requirements and adjudicate resources to address national priorities.

Hawaii DOT Studies Potential Flooding Impact on Infrastructure

The Hawaii Department of Transportation is looking at a range of studies that examine how the potential for sea level rise (SLR) due to climate change could impact transportation infrastructure. 

The most recent study, published in March of 2020 examined how direct marine inundation – which is when sea water levels rising above the current land levels – could affect Hawaii’s infrastructure but also at the impact of groundwater inundation, known as GWI.

GWI describes flooding that occurs as groundwater is lifted above the elevation of the ground surface and buried infrastructure; a difficult flooding type to manage since groundwater flooding cannot be stopped by coastal barriers such as sea walls. 

That study – conducted by researchers at the University of Hawaii at Mānoa School of Ocean and Earth Science and Technology – predicts that sea level rise will likely cause large percentages of Hawaiian land area to be impacted GWI, with Shellie Habel, lead author of the study, noting that the results “highlight the need to readjust our thinking regarding the flooding that accompanies sea level rise.”

Ed Sniffen, Hawaii DOT’s deputy director for highways and chair of AASHTO’s Committee on Transportation System Security and Resilience, estimated in a previous report that it would cost around $15 billion to protect all of the state’s coastal highways from the rising seas. The figure assumed $7.5 million for every mile of road that will need to escape erosion in the next 50 to 100 years and $40 million for every mile of bridge.

The agency began a vulnerability study in December 2019 to develop a comprehensive inventory of “potential extreme weather impacts” to Hawaii’s highway system; impacts that include GWI, SLR, and other natural disasters such as rockfalls and landslides.

Photo courtesy of Hawaii DOT

That’s in addition to a statewide assessment of SLR impacts conducted in 2017, which resulted in the Hawaii Sea Level Rise Vulnerability and Adaptation Report. That report predicted a 3.2-foot rise in global sea levels by 2100, one that could be reached as early as year 2060 under more recently published scenarios. Chronic flooding with 3.2 feet of SLR could result in approximately 25,800 acres of land in the Hawaii unusable, with roughly 34 percent of that potentially lost land containing a large amount of highway infrastructure in Maui, Oahu, and Kauai alone.

Currently, over 38 miles of major roads could be chronically flooded across the Hawaiian Islands, ranging from residential roads to sections of coastal highways such as Kamehameha Highway on Oahu. 

And much of that flooding could be from GWI rather than just direct marine inundation, thus not stoppable by traditional sea walls, which is why the Hawaii DOT is looking closely at creative engineering mitigation strategies for all flooding mechanisms for highways and bridge foundations.

Part of the agency’s flood mitigation planning is based on a study conducted for the Hawaii DOT by the University of Hawaii – called State Coastal Highway Program Report – released in August 2019. That report uses a new, detailed formula developed by the university to rank nearshore roads in order of urgency. Most of its suggested mitigation efforts focus on either “hardening” the roads and bridges or relocating them all together to higher ground. 

As a result, for the next two decades or so, the Hawaii DOT plans to strengthen and maintain the roadways as they are in place. For the future, it is also looking at elevating roadways and even relocating highways further inland and tunneling through parts of mountains to make that happen.  For instance, elevating the highway on Oahu’s Windward side could involve raising the road as high as nine feet. An alternative solution would be to relocate the highway further inland which would likely include tunneling through parts of the Koolau mountains at greater cost, the agency noted.

Recordings Available for AASHTO COIVD-19 Virtual Panels

The American Association of State Highway and Transportation Officials recently made recordings available of its weekly series of COVID-19 “virtual panels” held in April.

The AASHTO Committee on Transportation System Security & Resilience, through its Resilient and Sustainable Transportation Systems or RSTS Technical Assistance Program, sponsored those panels, which focused COVID-19 response and recovery issues faced by state departments of transportation.

The panels featured COVID-19 updates from the Federal Highway Administration, Transportation Security Administration, and Department of Homeland Security as well as from other state and local transportation agencies, followed by a question and answer session.

The panel recordings and materials can be accessed by clicking here.

AASHTO Committee Sponsors COVID-19 Panel Series

The American Association of State Highway and Transportation Officials Committee on Transportation System Security is sponsoring a series of “virtual panel discussions” to help state department of transportation leaders stay up-to-date on the latest news regarding the COVID-19 pandemic.

The panels will feature updates from the Federal Highway Administration, Transportation Security Administration, and Department of Homeland Security regarding the latest transportation implications of the COVID-19 outbreak. State DOT leaders will also get updates from other state and local transportation agencies from across the country, with an opportunity for open discussion.

The panels are also envisioned to serve as a “support group” for state DOTs facing COVID-19 emergency situations. But they are also forums for gathering and learning from the transportation impacts of the current pandemic and how they can be applied to future emergencies, including natural disasters such as hurricanes.

Another discussion thread will deal with how to improve multi-agency partnerships and emergency response efforts – especially in terms of building multi-agency ties before, and not during, emergency efforts. There will also be an emphasis on fine-tuning continuing of operations or COOP plans to help state DOTs maintain transportation systems during disease pandemics, as managing contagion outbreaks requires different protocols compared to COOP plans for wildfires, hurricanes, and the like.

The virtual panel series will be hosted weekly for the month of April. Additionally, a survey of state DOT needs or areas of interest regarding COVID-19 response and recovery will be launched at the April 8 session. Feedback collected will be used to inform subsequent sessions and additional technical assistance in response to the immediate and near-term response needs identified by state and local transportation agencies.

For registration details, please use the links below:

  • Wednesday, April 8, from 3:00 p.m. to 4:00 p.m. Eastern: click here.
  • Wednesday, April 15, from 3:00 p.m. to 4:00 p.m. Eastern: click here.
  • Wednesday, April 22, from 3:00 p.m. to 4:00 p.m. Eastern: click here.

The Ray: Fast Lane to Innovation

Imagine a highway that uses technology to track motor vehicles along an18-mile span ― that uses existing vehicle infrastructure to transmit radio data, as well as rest areas with testing zones and solar-powered charging stations.

Incorporating those features and others are part of the approach of the Georgia Department of Transportation long the said stretch of Interstate 85 via The Ray, which runs along the Ray C. Anderson Memorial Highway – so named for the late LaGrange, Georgia, native and businessman who promoted sustainability as a key aspect of future transportation projects.

The Ray – a high tech arterial roadway that lies south of Atlanta’s Hartsfield-Jackson Airport – begins at the Georgia/Alabama state line and ends in LaGrange at Exit 18. It’s a “future-forward infrastructure” project made possible by what’s known as a P4 – a public-private-philanthropic partnership.

Allie Kelly

What the state “has done with its partners in the advanced technology sector is learn from an 18-mile living laboratory that’s completely open to the public,” said Allie Kelly, executive director of The Ray. “It’s not a test track at a university, but a real-world environment that’s used by the 11.5 million drivers.”

The idea behind The Ray noted Kelly, “is to make highway transportation safer. Russell [McMurry, Georgia DOT commissioner] and I always talk about roughly 38,000 Americans who die in traffic crashes every year. They’re why we’ve worked together on various innovations” to make highway travel safer. 

One way to accomplish that goal, she explained, is to make testing easily accessible. And free.

“In 2016, we installed a drive-thru tire safety test station at Mile Marker 1 at a Federal Highway Administration rest area along The Ray’s northbound lane,” Kelly pointed out, highlighting the use of WheelRight technology at a tire safety station, which allows drivers to cruise over testing equipment “at 10 miles per hour or less”

She added that the technology evaluates tire pressure, tire tread depth, temperature, weight in motion and looks for damage on your tire sidewalls before printing out a report, all in about 10 seconds. “And it works on every vehicle type – aside from motorcycles,” Kelly noted.

She also noted that the Georgia DOT has built a dozen projects along The Ray since 2015, including the aforementioned connected vehicle infrastructure for radio data, which Kelly called “the biggest data pipeline the U.S. has ever seen, where we will have 105 million connected cars by 2022 sending out data packets at a rate of 10 times per second.”

The roadway also features a solar-powered electric vehicle charging station; a solar road called Wattways; and a megawatt solar array at the Exit 14 Diamond interchange, 40 feet from the pavement.

Russell McMurray, Georgia DOT Commissioner

Georgia DOT’s McMurray said such innovations are the result of “a case-by-case cost-sharing concept, with The Ray as a frequent financial partner,” in addition to private industry donating materials. 

He said other states are taking notice of Georgia’s approach.

“While Georgia is definitely leading the way in innovative partnerships like Georgia DOT’s partnership with The Ray, one example I can cite is the Massachusetts Department of Transportation Solar Energy Program,” McMurry noted. “[It] focuses on ground mount solar [photovoltaic] generation facilities within state highway layouts throughout Massachusetts. The goal is to create energy savings by procuring electricity at a favorable rate, generate revenue by using unused state land and support the Commonwealth’s green and clean economy.”

There are various facets to what is being accomplished via The Ray that include not only data collection and energy creation, but environmental aspects, too – such as the evaluation of different types of plants-pollinators and native species. For instance, the solar farm covers a natural habitat with native grasses and flowers, among others.

From environmental and safety standpoints, “all of the shredded tires on an interstate from blowouts and are very dangerous and they are often the byproduct of loss of life,” Kelly said. “While this effort is about safety, we’re also wasting two billion gallons of fuel every year because we can’t get our tire’s air pressure right.”

On that note, she added that “the big winners” traveling The Ray are fleets. “School buses, city transit buses and 18-wheelers coming out of ports can use every weigh station on I-85,” Kelly pointed out. “That’s how we correct those tire issues that are leading to tire failure, wasted, fuel, and dangerous crashes.” 

While made with sadness and frustration, Kelly emphasized there is hope in that observation, as well.

“The technology we need to make improvements exists,” she stressed. “We just need to start using it.”