Engineers from FPL and the VA Inspect 134-Year-Old Milwaukee Medical Center Building

The first building in what is now the Clement J. Zablocki Veterans Administration Medical Center (VAMC) in Milwaukee, Wisconsin, was originally approved for construction by President Abraham Lincoln just one month before the end of the Civil War, for the care of disabled soldiers. That structure was completed in 1869.

Originally called the National Home for Disabled Volunteer Soldiers and nicknamed the “Old Main,” the Zablocki VAMC now consists of 20 buildings.

Adam Senalik, FPL Engineer, visually inspecting the studs of a wall on the top floor of Building 7 at the Zablocki VAMC.

Last week, it was time for an inspection of Building 7 – the Soldiers’ Home. Like Buildings 2 and 5, it was built as a barracks for soldiers receiving care at the Milwaukee Soldiers Home. Consisting of three stories and a large basement foundation, the Soldier’s Home, designed by celebrated architect Henry Koch, was ready for business in 1888. Building 7 now supports the offices of the Compensated Work Therapy Department. New IT requirements require the VAMC to update the structural integrity of some of the older buildings.

Bob Ross, FPL Engineer, investigating the structural members in the wall system on the top floor of building 7. Note that the outer layers of the wall have been removed to expose the structural members.

To that end, Forest Products Laboratory Research General Engineers Bob Ross and Adam Senalik took the 90-minute drive to Milwaukee to join Erik Billstrom, on-site engineer for the VA, to carry out the necessary structural analyses.

Erik Billstrom, VA engineer, examines a large white pine timber in the high ceiling of the basement maintenance room and finds he is easily able to remove wood samples by hand.

According to Bob and Adam, FPL regularly receives requests for structural condition assessments, mostly dealing with historic wood structures, structural assessment, inspection, and assignment of allowable design values.

“We usually try to provide direct assistance to other Federal agencies and Departments,” said Bob. “This is especially true for the DoD and Veterans’ Administration.

“What matters most here,” added Bob, “is that this campus does good things for veterans.” The Zablocki VAMC serves more than 64,000 U.S. veterans every year.

Bob added that the book he coauthored, Wood and Timber Condition Assessment Manual, now in its second edition, summarizes structural condition assessment research currently used for wood and timber structures. The publication can be found at:  https://www.fpl.fs.fed.us/documnts/fplgtr/fpl_gtr234.pdf.  A previous FPL LabNotes article provides a summary of the manual here:  https://www.fpl.fs.fed.us/labnotes/?p=4599.

Bob Ross reveals a deteriorated nail from the basement ceiling

Starting on the third floor of building 7, the three engineers began to examine the condition of the walls and ceiling.

“It’s in pretty bad shape,” said Adam. “But about what we expected.” Previous engineering analyses had found that the structural beams were not designed for heavy weight. 

The group then climbed up into the dark attic above the third floor and removed a few samples of wood. The blackened strips of wood appeared as if they had been in a fire.

“Maybe they were at one time,” observed Bob. “Further analysis will tell us.”

Satisfied with their inspection and the samples they had acquired, the analysts moved down to the utility room on the basement level. Here, the late 19th-century origins of the building were even more apparent, with period arches and a brick wall that had survived more than a century of water damage. The wall appeared not unlike a medieval dungeon in its heavily “blurred” condition.

Erik set up and climbed a tall step ladder to examine a large white pine timber across the ceiling of the basement. He reached in and was able to effortlessly lift spacers out of the surrounding structure. Finally, the three engineers placed all their gathered samples into large, labeled plastic bags.

“It was a good inspection,” Adam concluded. “I only hope that this building can be saved.”

Reducing Wildfires through Better Utility Pole Inspections

They can pop up almost anywhere.

“They” are wildfires, which can result in loss of human life and lead to billions of dollars of property damage every year in the United States.

Hundreds of failures in electrical utility poles across the nation are one of the leading causes of these disasters. In Idaho alone, nearly 300 wildfires have been caused by utility pole failures in the past 15 years – an average of 20 wildfires every year.

Electrical utility pole failure is one of the leading causes of wildfires nationwide. The sheer number of poles involved makes regular inspections challenging – but the Forest Products Lab is finding new ways to carry out pole inspections quickly and easily. (Forest Service photo)
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FPL Scientist and UW-Madison Bring Science and Art Together

Alex Wiedenhoeft invention contributes to new Audubon Exhibit at the Chazen Museum of Art


Detail of Carolina Parrots from The Birds of America, John James Audubon. Photo courtesy of the Chazen Museum of Art

Alex Wiedenhoeft has contributed so much of his hard work and knowledge to the Forest Products Laboratory in the more than 20 years he has been with us. One of his most useful inventions is the XyloTron, a desktop device that provides high-resolution images of wood.

In his effort to make the XyloTron less costly and more portable, Alex also developed the XyloPhone, a small device that attaches to a smartphone and provides the same resolution as the much larger XyloTron.

In just a few months, the Xylophone has contributed greatly to the ability of scientists in the field to identify and photograph wood. But not just wood.

Artist Emily Arthur, associate professor in the UW-Madison art department, learned about the XyloPhone through her colleague Anne Pringle, professor of Botany at UW-Madison, who studies lichens and fungi in her lab. During Emily’s ongoing collaborative research with Robin Rider, curator of special collections, Memorial Library, the XyloPhone became a way to examine rare books and works on paper.

“I knew this device would be invaluable for the purposes of this research,” said Emily Arthur. “And I was right! Being able to examine the hand-colored engravings from The Birds of America at such a detailed level has revealed new information on the printing techniques that were used in its production between 1827-1838.”


Alex Wiedenhoeft demonstrates wood identification using the XyloTron system. He also developed the XyloPhone as a smaller, more portable device that attaches to a smartphone, but with the same remarkable scanning ability. Photo by Andrew Averil, Hardwood Floors Magazine

The focus of the exhibit at the Chazen Museum of Art is not just the gorgeous creations of the renowned naturalist, John James Audubon, but in particular the methods that formed a tradition of exactitude in engraving that lies behind the work of printmakers like Robert Havell, Jr.

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FPL Scientist Reflects on 20 Years with the Lab

Charles Frihart – or Chuck, as he prefers to be called – has just retired after 20 years with the Forest Products Laboratory. Before that, he worked in industry even longer. The total experience has left him with a unique perspective.

“Before FPL, I spent most of my time in New Jersey,” Chuck reminisced. Even though he lived and worked there for most of his career, Chuck says that he and his family always said we were temporary residents of New Jersey, “because we always considered Wisconsin home.”

Chuck started out working for a pulp and paper company. He then joined Henkel, which is the world’s largest adhesive company.

Chuck says he was happy to have the opportunity to return to Wisconsin in 2001 to work at FPL. His job was to modernize the wood adhesive group through his knowledge of adhesives in non-wood fields.

When paper pulp is manufactured, lignin and other parts of the wood are removed to release cellulose fibers. These byproducts form “black liquor,” which is seven times more abundant than the final paper pulp. This material is concentrated and put through a recovery boiler to recycle the pulping chemicals and provide energy. The pulping by-products are converted into chemicals for adhesives, printing inks, fragrances, and other products.

In industry, Chuck worked on what to do with chemical byproducts from the pulping process.

Charles Frihart at work in the Forest Products Laboratory

“I was mainly working with the fatty acids and what to do with them,” explained Chuck. “Fatty acids are similar to hydrolyzed vegetable oil. Basically, I was working on adhesives for many applications and generated 29 patents.”

Chuck’s interest in bio-based compounds goes back to his college days.

“I’ve always studied these natural products from my work on nucleic acids in college, through industry work on fatty and rosin acids, and at FPL on protein adhesives.

“I was hired at FPL not because I knew a lot about wood adhesives, but because I knew adhesives in general,” Chuck continued. “I was also brought in because FPL wanted someone with a different perspective, which meant being comfortable with working in industry.

“Most of my years with the paper industry, we had a very good executive vice president who wanted people to do a combination of applied and fundamental research. Sometimes you have people who are very good at fundamental research and spend all their time doing it, but have no idea how to make useful products, and the people in industry tend to get so attached to doing the applied work, that they forget fundamental science, so you have to think on both levels, because they’re not mutually exclusive.

“They complement one another and you can make more progress when you combine the two. My goal has always been to make something new, but at the same time understand the fundamentals as well as I can, and not get tied up in either one.

“Trial and error only gets you so far, so my thing has been to really understand how wood adhesives work and why they fail. Wood adhesives don’t normally fail except under wet conditions, and in some cases, with some of the adhesives applications, you also need temperature resistance, as in a fire, and that was a problem.”

The adhesives group needed a team of  specialists in material science, analytical chemistry, mechanics and wood chemistry. The first addition involved Chuck’s welcoming Daniel Yelle, who does adhesive chemical reactions with wood polymers and lignin chemistry. “We have studied lignin, but few people have figured out how to get useful adhesive products out of lignin,” explained Chuck. “Although there have been about 200-some papers that have claimed that success, it’s actually only used marginally on a commercial level.

 “The other area for bio-based adhesives is proteins, and soy beans specifically,” said Chuck. “Besides oil and protein food products, it’s basically used as animal food. We don’t produce much tofu or other kinds of fermented soy-based products for people as they do in China and other parts of East Asia. Also, soybeans have a high percentage of lysine, which is an amino acid and an important nutrient for animals.”

Chuck said that it is very difficult to understand proteins in adhesive applications because proteins can change properties very easily, and it’s hard to measure when the properties of proteins change. Chuck pointed out that soy is the major product that has been used in interior wood adhesives in the United States for over 10 years.

Among the major accomplishments in wood adhesives at FPL, Chuck points to the work of Joseph Jakes and Nayomi Plaza Rodriguez, “because they have developed an understanding of the fundamental structure of wood cell walls.”

Joseph works with Argonne National Laboratory, and Nayomi works with Oakridge National Laboratory, both run by the Department of Energy. Chuck said that the major advantage to these collaborations is that the other labs have extremely expensive experimental equipment and allow FPL scientists to write proposals and have access to it. “What makes us different is that we combine chemical probes made by Linda Lorenz with the analysis of wood cell walls to understand how adhesives react with wood itself,” said Chuck.

“The real challenge with adhesives is that they typically only work well only under dry conditions. It’s when things get wet that many of the adhesives fall apart and you have joints coming apart on wood products, et cetera. And so you have to understand the wood swelling and shrinking properties and how it’s doing that, and what Joseph and Nayomi and the others have done is just fantastic. So I can’t claim credit; I had the concept, but I didn’t know how to do it, so my role was more of an instigator, rather than the person who figured out how to do it. And it made FPL the leader in understanding wood cell walls and the behavior of wood.

“FPL is fortunate to have a core of very bright young scientists who can carry us through for the next few decades and who are doing things that nobody else is doing.

“At a certain point,” Chuck said wistfully, “your science becomes dated, and you need to be replaced by people who have different knowledge and abilities of how to carry out science. I’ve enjoyed the science and the people at FPL. Being involved in science is in my blood and will continue, just on a lower priority.”


FPL Scientists’ Work on Moldable Wood Is Featured on the Cover of Science

The article “Lightweight Strong Moldable Wood Via Cell Wall Engineering as a Sustainable Structural Material,” coauthored by Forest Products Laboratory research scientists Junyong Zhu, Vina Yang, and Marco Lo Ricco, with lead author Prof. Liangbing Hu at the University of Maryland-College Park, was published in the Oct. 22, 2021 issue of Science Magazine as the cover article.

“In this work,” the article states, “we demonstrate how cell wall engineering can render wood foldable and moldable while simultaneously improving its mechanical properties – endowing wood with a structural versatility previously limited to plastics and metals.”

The Moldable Wood issue of Science
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