a bridge too far~ctm
Lehigh University researchers’ novel approach combining climatology, hydrology, structural engineering, and risk assessment could help communities fortify bridges against scour caused by extreme weather
Lehigh University
Climate change will ultimately affect our bridges. But to what extent?
That is the essential question addressed by Lehigh University researchers David Yang and Dan M. Frangopol in a paper recently published in the ASCE Journal of Bridge Engineering.
“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains,” says Yang, a postdoctoral research associate in civil and environmental engineering at the P.C. Rossin College of Engineering and Applied Science. “For this paper, we’re looking at increased temperature as well as increased precipitation and their impact on bridge safety. The challenge here was that we didn’t know how to quantify those impacts to predict scour risk.”
Scour is the primary source of bridge failure in the United States. It’s created when floodwaters erode the materials around a bridge’s foundation, creating scour holes that compromise the integrity of the structure.
For their paper, Yang and Frangopol, a professor of civil engineering and the Fazlur R. Khan Endowed Chair of Structural Engineering and Architecture, had to fill the gap between the climate data and the structural safety quantification. They did so by using hydrologic modeling to convert climate simulation data to flow discharge data in the Lehigh River. The Lehigh River is a 109-mile long tributary of the Delaware River that runs through the city of Bethlehem, Pennsylvania, where Lehigh University is located.
“We took a holistic approach,” says Yang. “It started with a global climate model that was downscaled to regional hydrology, then we used structural engineering to get the failure probability of a structure in a future flooding event. From that, we could assess, does this structure failure pose certain risks to a community? So our model included these four steps of climatology, hydrology, structural engineering, and risk assessment.”
It’s the first paper to date that has combined all four steps to quantitatively look at the effect of climate change on bridges, he says.
In developing their model, the pair considered different climate futures and global climate models provided by the Intergovernmental Panel on Climate Change. To estimate the foundation depth of older bridges spanning the Lehigh River–information that is often unavailable–they developed a method to back-calculate the depth based on condition ratings from the National Bridge Inventory. They also took a regional and life-cycle approach to their analysis.
Frangopol is world renowned for his pioneering work in life-cycle engineering, which uses computational analysis to determine the long-term value and risk associated with infrastructure investments. In 2019, he was awarded the George W. Housner Structural Control and Monitoring Medal in recognition of his groundbreaking work and leadership in the field. This is one of many awards and honors bestowed on Frangopol from several professional organizations. Indeed, Frangopol, as part of a research team consisting of his former and current PhD students, will receive the 2019 State of the Art of Civil Engineering Award during the upcoming annual convention of the American Society of Civil Engineers (October 10-13, 2019) in recognition of their paper, “Bridge Adaptation and Management under Climate Change Uncertainties: A Review.” It’s the third time Frangopol will receive this prestigious award.
Taking such a regional and life-cycle approach, says Yang, was a novelty for this paper. “Bridges have a lot of microenvironments, and if you only look at one bridge, it’s really hard to capture the trend and get the increased risk from climate change,” he says. “So we broadened this analytical horizon both spatially and temporally to capture long-term trends.”
Of the eight conclusions Yang and Frangopol reached with their model, the most surprising was the extent to which the frequency of flooding may change.
“We realized that a 20-year flood may now become a 13-year flood at the end of the century, so that frequency nearly doubled,” says Yang. “This is why climate change may induce an increased risk to infrastructure.”
Perhaps their most important conclusion involves the question of mitigation. Specifically, what engineering measures should be deployed to reduce risk, and in which bridges.
“The reality is that budgets are limited,” says Frangopol, who is also affiliated with Lehigh’s Institute for Data, Intelligent Systems, and Computation (I-DISC) and the Institute for Cyber Physical Infrastructure and Energy (I-CPIE). “So it’s important to be able to determine, what is the priority here? You need to know the location of the bridge. For some communities, the failure of a bridge could be disastrous. For others, a bridge may not be as critical. This model helps you make that kind of decisions because risk is not only based on safety but also on the consequences of failure. You might have two bridges at the same probability of failure, but the consequences of that failure could be very different.”
Focusing on bridges along the Lehigh River was an obvious choice given their location, but both Yang and Frangopol are eager to share this model, not only locally, but with all communities looking to assess their infrastructure.
“We were inspired to do this research in part because historically Bethlehem was hit by multiple floods since 1902, and they had a significant impact on the community, so flooding is a significant hazard throughout the Lehigh River watershed,” says Yang. “We wanted to devise something that the community can use to become adaptive to future climate change,” says Frangopol.
###
The research reported in this paper was supported by the U.S. National Science Foundation Grant CMMI 1537926 “Life-Cycle Management of Civil Infrastructure Considering Risk and Sustainability,” (2015-2020) with Dr. Dan Frangopol as the sole Principal Investigator.
Related Links:
- Lehigh University Faculty Profile: Dan M. Frangopol
- ASCE Journal of Bridge Engineering: “Physics-Based Assessment of Climate Change Impact on Long-Term Regional Bridge Scour Risk Using Hydrologic Modeling: Application to Lehigh River Watershed”
- Rossin College News Center: “Frangopol awarded 2019 George W. Housner Structural Control and Monitoring Medal”
- NSF Award Abstract: “Life-cycle Management of Civil Infrastructure Considering Risk and Sustainability”
- 2019 ASCE Convention
- ASCE State-of-the-Art of Engineering Award
“The most common causes of bridge failure are structural and design deficiencies, corrosion, construction and supervision mistakes, accidental overload and impact, scour, and lack of maintenance or inspection.” (Biezma and Schanack, 2007).
Strangely, no mention of Global Warming/Climate Change.
My thoughts on reading the title of this article was to think about the Firth of Forth bridges.
The Forth Bridge has stood for more than a century and taken loads more than double original design at speeds greatly in excess of the speeds capable when it was designed. Add in being rammed by large ships and being bombed, It continues to perform its original function superbly.
The Forth road bridge (mark1) was effectively condemned within 10 years of completion.
Road bridge (mark2) has not been standing long enough to draw any conclusions.
Where in this little tale does “climate change” come into the story?
“The Forth road bridge (mark1) was effectively condemned within 10 years of completion”
But is still carrying traffic after 55 years of use. It takes maintenance to keep it functioning, which is hardly a surprise. Road bridge 2 was intended as a backup in case bridge 1 needed really major repairs, like replacing the main cables, which would take it out of service for a few years. Which it hasn’t yet.
“The Forth road bridge (mark1) was effectively condemned within 10 years of completion”
Seems that it was ineffectively condemned.
Exactly so. We don’t have to worry about scouring a century from now. We have to worry about lack of maintenance right now. link America’s bridges are crumbling.
There’s also shoddy construction and poor design to worry about.
“Climate
changewillultimatelyalways affect our bridges.”Fixed it for him.
Right — climate change my arse. And any decent engineer knows corrosion from road salt (used in cold weather!) and lack of both maintenance (paint) and proper/regular inspections are why bridges fail.
Just another case of grant-seeking.
exactly.
See my comment below. These professors are merely seeking rent from the climate scam.
Jumping on the gravy train.
Corrosion on bridges and overpasses from winter road salt is the major threat to their structural integrity, not some marginally increased scour on the footings/casements.
If anything more rainfall in the springtime helps to wash and flush the salt from the structures and into the rivers and out to sea.
Beng135. Good comment. I was thinking that this guy should do what I do when I don’t have any helpful ideas, I mow the yard.
No manmade object lasts forever.
Scouring is totally dependent on water flow and river sedimentation, nothing else. Many factors affect those, and they are never stagnant.
Mountains are brought down by the weather.
Shameless research grant grubbing.
The most common cause of bridge destruction is removal. Small bridges, like those studied, will become obsolete and be replaced long before the end of the century. even for larger bridges, we see far more videos of dramatic bridge demolition than stories of bridge collapse.
What a load of tosh
“… We know climate change will increase the frequency and intensity of natural hazards …… For this paper, we’re looking at increased temperature …”
No looking at decreased temperatures due to a climate changing to a cooler one? So why not skip the middleman labeling and go straight to the point by calling the global warming issue? …. Oh, wait ….
Dont see David Yang addressing this (examples below) ice Mr yang
https://youtu.be/eoC8M4L_YSg
https://youtu.be/BjZBvhQ77_A
https://youtu.be/6DxG9yOS1dQ
“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains,” says Yang
We do?
Of course we hear it everyday in the Propaganda Press and pop culture passes this certainty around like the collection plate at a revival meeting, hallelujah.
Why they even write it into scripted Prime Time Network Comedies, yet “everybody knows” there is nothing funny about Man Made Global Warm…aahhh climate change. which is more than enough justification to pay the subscription increase in a monthly Netflix subscription.
that’s when I stopped reading. The rest is b’sht!
Repeating something over and over doesn’t make it true. Especially in engineering!
They “know climate change” causes all these events when the IPCC doesn’t even know for certain. It would be useful if they would at least check the empirical data on these events before stating they “know” about the future. Is this research just more fruit from a poisoned tree?
So Mr Yang, would you like a large amount of grant money to spend?
Yes, “we” do.
“We” being those who ignore the facts.
All hail the omniscient models.
So really all of these studies anymore are just models tuned to milk grant monies.
Bingo!
“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains,” says Yang…
Like when, Yang?
An Engineer‟s Critique of Global Warming „Science‟
— Questioning the CAGW* theory —
http://rps3.com/Files/AGW/EngrCritique.AGW-Science.v4.3.pdf
This article, by an engineer, is excellent!
Burt Rutan isn’t just your ordinary garden variety engineer.
That is quite a link!
+1
Another of those “we knows” that seems they don’t even give rudimentary acknowledgement to other studies.
“There was low confidence due to limited evidence, however, that anthropogenic climate change has affected the frequency and magnitude of floods.”
“Numerous studies leading up to and after AR5 have reported a decreasing trend in the global number of tropical cyclones and/or the globally accumulated cyclonic energy (Emanuel, 2005; Elsner et al., 2008; Knutson et al., 2010; Holland and Bruyère, 2014; Klotzbach and Landsea, 2015; Walsh et al., 2016)”
https://www.ipcc.ch/sr15/chapter/chapter-3/
“Fire is an essential Earth system process that alters ecosystem and atmospheric composition. Here we assessed long-term fire trends using multiple satellite data sets. We found that global burned area declined by 24.3 ± 8.8% over the past 18 years. ”
http://science.sciencemag.org/content/356/6345/1356
It appears the professors started with global climate model, the accuracy of climate change models has been suspect over the last 20 years as they overstate the amount of warming vs. what has actually occurred, and then downsize an inaccurate model to a regional hydrological model. I guess that gives their study some basis, but it’s more like a foundation on shifting sand at a beach.
Once again, an effort to conflate weather to a changing climate (which has been changing for eons). It may have some relevance over 500 to 1000 years, assuming they have the direction of climate change correct, not so much for the typical 75 to 100 year design life. I’d think collecting more historical data as we move forward and changing design intensities associated with durations and frequencies will be more accurate and provide better factors of safety.
“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains,” says Yang, a postdoctoral research associate in civil and environmental engineering at the P.C. Rossin College of Engineering and Applied Science.
The level of idiocy of these pseudo-scientists is much worse than I thought.
I hope this clown will never bild anything, for the sake of the population.
Acid sea is going to eat through the bridge foundations.. right?
After the extra heat weakens it because when engineering bridges you build them to such exacting tolerances that even a fraction extra of anything and down they come 🙂
How are they going to transform Iron into Steel for strong bridges without Coal?
It all depends where you are on your perception of the risk. Bridge scour in the UK concern focusses on scour of sand and gravels, in Taiwan for example where there are heavy Typhoon events they are concerned about movement of rock blocks the size of small houses!
Extreme chunky scouring!
Those will “erode” a foundation pretty fast.
From the article: ““Bridges have a lot of microenvironments, and if you only look at one bridge, it’s really hard to capture the trend and get the increased risk from climate change,” he says”
He is assuming such a thing as human-caused climate change exists. There is no evidence this is the case. He is assuming too much, which is a common failing of people who believe in, or promote, human-caused climate change. Human-caused climate change is a speculation, and this study, and all studies of this kind, are built on that basic speculation. If the basic assumptions are wrong, then that makes all subsequent studies, based on those assumptions, wrong.
Human-caused climate change = A House of Cards.
House of Cards
https://en.wikipedia.org/wiki/House_of_cards
“A house of cards (also known as a card tower or a card castle) is a structure created by stacking playing cards on top of each other pyramidally. “House of cards” is also an expression that dates back to 1645[1] meaning a structure or argument built on a shaky foundation or one that will collapse if a necessary (but possibly overlooked or unappreciated) element is removed.”
end excerpt
liked for the posting not for the content of their “study”
as more than mentioned already we know is irking me as a widespread fasls claim heard daily and utterly rubbish
claimants usually know jackschitt Ive noticed.
might be better to spend money on really needed older bridge repairs than this rubbish
The great thing about climate change is that whatever research you do, you can now add the phrase “climate change” to the title and publish it as “climate change impact research”. That greatly increases your funding possibilities. Some of the titles can get strange but it doesn’t seem to bother anyone. Pls see ….
https://tambonthongchai.com/2018/06/21/climate-change-impacts1/
Great list, sir! Yes, a few of those titles made me smile this morning.
I must admit I stopped reading here: ‘“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains,” says Yan’
Why don’t we study the impact of graft, corruption, and bad management on bridge maintenance? This has a much greater impact on our current reality than does climate change, though I will admit that a new ice age is likely to play havoc with our infratructure, bridges included.
What worried me was the comment that a change from a 20 year to a 13 year flood frequency had ‘almost doubled’ the frequency. I would like a bit more accuracy than that.
Yep, heavy hyperbole there. Almost exactly a 1/3rd increase is ‘almost doubled?’
And I don’t know of anyone who looks at 20 yr floods for anything. 10, 25, 50, and 100 are the standards. Engineering post-docs should know better.
If I applied for a grant to study:
“The Impact of the Reduction of the Adhesive Co-efficient of Fairy Floss to Adhere to a Wood Paddle Due to Climate Change”
What would be my chances be of getting approval?
Simply adding “Due to Climate Change” at the end of any idiotic research proposal virtually guarantees a grant.
Bingo
What a novel idea – take a subject, any subject whatsoever, pick your fave climate model or models, and spice them up with alarmist “thought”, combine them, and presto, you’ve got a “study”. And you get paid to do it. It’s genius. Have they done one yet showing how “climate change” will stunt children’s growth yet? Dibs! I call dibs. I want on that gravy train.
You can have that one, but I want:
“Climate change causes deforestation, ermm.. due to increased toxicity of squirrel turds, uhhh.. because CO2 chemically alters nuts”.. yeah
Add latent feminist, and you have a winner.
/sarc
Well the UK has seen multiple bridge failures, mostly of old stone structures, landslips, a seaside railway embankment washed out, a near failed dam and other infrastructure impacts since 2000, in places where extreme one day rain events or prolonged heavy/exceptional rain have brought flooding.
That’s the climate impact we already see on the UK
(Things affected I mentioned above have been in place since the mid 19th century or earlier without previous flood/weather damage)
If anything has changed, it’s CO2 that caused the change.
Even when it hasn’t changed, just declare that it has and insult anyone who disagrees.
Come on Griff it was the extra CO2 which being so heavy clearly caused the problem.
“Things affected I mentioned above have been in place since the mid 19th century or earlier without
previous flood/weather damagesufficient maintenance”There, fixed it for ya
“climate impact we already see on the UK” Stuff and nonsense giffiepoo. Utter falsehoods spoken by delusional climate religion groupies.
Nothing whatsoever to do with science, weather or climate.
A) Somehow giffiepoo conflates “multiple bridge failures” with old stone structures, landslips, seaside rail embankment, a near failed dam (whatever “near failed” is supposed to mean), and other infrastructure…
B) giffiepoo fails to explain why his alleged bridges that are designed to easily weather annual temperature changes of over 50°F (10°C), 100 year and 500 year storms including gale force wind speeds, and 100 year floods.
Somehow an alleged temperature increase well under 2°C, and a very slight atmospheric increase of carbon dioxide causes these failures.
Keeping in mind that storm severity has decline during the global warming mantra years…
giff does not see an “climate impact” in the UK; it preaches belief and dooms not engineering challenges that are already covered by any reputable engineer.
So let us now when all the New Stuff is affected and not that which was installed around the turn of the last century
Why didn’t you name one example? Oh I can name some…like this one, built (for the second time) in the 1700s https://en.wikipedia.org/wiki/Tadcaster_Bridge
The thought never occurred to you that things which “have been in place since the mid 19th century or earlier” get more vulnerable with age? You’re going to pretend they are good as new when 100+ years old? You’re going to pretend that there’s no cumulative damage or issues?
It’s a good thing you never tried your hand at studying engineering.
Really? Why? Explain!
I get fed up with this kind of evidence-free statements. Doesn’t (almost) every single sentence in a scientific require some sort proof/evidence/argument/reference?
“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains,”
Bullshit
What is next?
Building 7 collapsed because of climate change?
More ice is bad and less is good.
Either way…design for reality and plan maintenance accordingly.
If we continue to see rising temperatures we can expect lower maintenance costs ON EVERYTHING exposed to cold weather.
The only good thing that might come from colder weather is greater public distrust of Climate related experts….something that’s already running pretty high.
Turns out that Chicken Little is not the best publicist.
“We know climate change will increase the frequency and intensity of natural hazards like hurricanes, heat waves, wildfires, and extreme rains” Bullshit.
“Climate change” to cause increased drug use and homelessness. Dibs on that, too. Hey, there’s plenty for everybody.
Running water causes scour, more running water causes more scour. Academia wins again…