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About an hour into a recent test of cross-laminated timber at the Hinsdale Wave Research Laboratory in Corvallis there was an earsplitting groan culminating in a crack, followed by the sound of a little piece of metal rattling on the ground.

Somebody located the half of a screw and presented it to Melina Massari.

鈥淢ust be a European screw,鈥� he told her. It was an obvious dig at the Italian researcher. She laughed it off.

Cross-laminated timber (CLT) has been used in Europe since the 1990s, despite a relative lack of product standards. Now, in Oregon, it鈥檚 as hot a topic as there is. The stylish building product is generating interest from the timber industry and environmentalists alike.

Though it鈥檚 still partly subsidized by the government, CLT is being called revolutionary for its potential to shorten construction schedules and bring back jobs to timber country. But because it’s new 鈥� at least to America 鈥� it first has to be tested for seismic resiliency, among other things. That鈥檚 where young researchers like Massari and others at Oregon State University are leading the way.

鈥淚 like this material a lot,鈥� she said. 鈥淚 think in the future, in construction, designing with something like this will be as common as concrete or steel.鈥�

Interested parties

Friday was Massari鈥檚 big day 鈥� the culmination of an academic career that鈥檚 spanned most of her life. The 30-year-old doctoral student was to fly home to Piandimeleto on Monday, the same day her student visa was to expire. The test had to happen, and there was uncertainty as late as Thursday afternoon whether it would.

She and her team were up until midnight the night before connecting equipment. But the Ph.D. candidate from the University of Bologna hadn鈥檛 been procrastinating, according to her OSU-based adviser, Andre Barbosa.

鈥淚n engineering, we keep our schedules,鈥� he said.

Seven months of hard work and wrangling in Corvallis had led to this day, and to add to the importance, a small crowd was on hand in the Hinsdale lab. The Beaver-orange hardhat-wearing contingent included university officials, donors to the project, and, for a few minutes, U.S. Rep. Suzanne Bonamici, D-Ore., and her entourage. (She was to be briefed on CLT later that day in a different part of campus.)

鈥淯sually we don鈥檛 have this many people, but there is a lot of interest in CLT,鈥� Barbosa said.

Before getting going, Massari said she felt excited, despite some nerves.

鈥淭his is not common for me, but I feel great,鈥� she said. 鈥淚 get to do something real, instead of just doing work on the wall of a classroom.鈥�

On hand Friday was John Redfield of the D.R. Johnson mill in Riddle, the only U.S. mill certified to produce CLT and donor of the 8-foot-wide, 16-foot-tall specimen used in the test. Redfield said he gets inquiries most days from people interested in buying CLT, from homeowners to commercial developers.

Research is ramping up to devise building systems for CLT and other mass timber products, including for tall buildings, said Judy Liu, a civil engineering professor focusing on steel building systems who watched the test. Notably, work is being done at Colorado State University to devise standard seismic specifications.

鈥淲ood definitely seems to be getting into markets that aren’t just low-rise residential or commercial,鈥� Liu said.

Research projects like Massari鈥檚 put structural components like walls and floors to the test, but testing will be needed on full building systems before CLT is broadly accepted in the U.S. That type of research would obviously be much more expensive, Barbosa said.

Former OSU men鈥檚 basketball coach Jimmy Anderson was also on hand at the lab. His sister-in-law, Susan Merrill, had hosted Massari during her stay in Corvallis. Through Merrill, Massari met Yohn Baldwin, owner of Baldwin General Contracting, one of the largest general contractors in the mid-Willamette Valley.

It was only a few months ago that Massari 鈥� the first in her family to attend college 鈥� badly needed funding for her project. It turned out Baldwin was eager to support research into CLT, having recently learned about it.

鈥淎fter a couple of meetings with Melina, I realized what an incredible person she is and what an incredible project she is working on,鈥� Baldwin said. 鈥淪o we got very involved.鈥�

He contributed $15,000 and connected Massari with professionals who helped her design, engineer and build project components. He even worked with her on some initial rough sketches.

Baldwin said he鈥檚 learned much about CLT since meeting Barbosa and Massari. The more a general contractor knows about a building product, he said, the more he can advocate for it during the design-build process.

鈥淎ndre told me yesterday that from a strength-to-weight ratio, a CLT panel is superior to reinforced steel,鈥� he said. 鈥淚 wouldn鈥檛 have guessed it.鈥�

Self-centered

CLT is a structural composite panel consisting of layers of dimensional lumber glued and pressed at right angles. With few seismic codes in Europe, there hasn’t been much seismic testing of CLT.

The tests at the Hinsdale lab don’t exactly simulate a real earthquake; Massari鈥檚 team pushed its specimen through the types of displacements that would occur in one. Her project tested the first self-centering rocking wall system using a Douglas fir CLT wall panel.

For the test, the team devised a novel seismic connection system consisting of a structural fuse that can be replaced after an earthquake. The wall was also post-tensioned so it would self-center following a seismic event.

First, they started with small displacements, to remove slack in the machine and find their parameters. Then they increased the displacements, watching for the effects of flexure, shear and the rocking of the wall.

Soon bolts were shooting off the panel.

鈥淲e鈥檙e measuring all the possible motions of the CLT panel,鈥� Barbosa said. 鈥淲e鈥檙e going to keep (increasing) the load and increasing the displacements. At different levels, we鈥檒l learn new things. It’s not pass-fail test, but we will test it to failure.鈥�

OSU master鈥檚 student Kyle Sullivan is doing research similar to Massari鈥檚, but his focus is on the way CLT floor connections perform in seismic events. He鈥檒l run his tests in a few weeks; for now, D.R. Johnson is helping to prepare his specimens.

Before coming to OSU from Maine, Sullivan studied civil engineering at Columbia University. He used to think of wood as 鈥渟mall-scale,鈥� until learning about CLT in 2014. He started asking building professionals what sort of work needed to be done, which led him to his current project. He鈥檚 about to accept a job in Canada, where building codes are less 鈥減rohibitive鈥� toward CLT.

鈥淔or me, I鈥檝e always been interested in sustainability and clean energy, and I did physics in undergrad. So I feel that this is a real good conglomeration of my interests,鈥� he said.

The O.H. Hinsdale Wave Research Laboratory houses a number of other research efforts relevant to civil engineering (as well as the long wave flume used for tsunami simulation that bisects the facility). There鈥檚 a freezer, where products are tested in the cold. On Friday, a team of students tested attachable concrete T-beams with titanium reinforcement (they could be used in seismic retrofits of highway bridges).

At the lab鈥檚 other end, in a project funded by architecture firm Skidmore, Owings & Merrill, a contractor laid a thin layer of concrete atop CLT panels, for testing of sound transmission. Some people think these hybrid panels will be more common in the future than plain CLT.

In the end, Massari said her test went well. Team members observed some things they were expecting, and some things they weren鈥檛. For one thing, the panel dissipated energy in at least one way they hadn鈥檛 foreseen.

Massari will now co-author a paper with Barbosa and colleague Marco Savoia based on their results.

鈥淭here is a lot of things going on with (CLT),鈥� she said. 鈥淎nd I hope that someone else continues this work.鈥�