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Big changes have come to Portland Community College鈥檚 Metropolitan Workforce Training Center. Framing is under way for a new mass-timber training center 鈥� next door to the existing one.

Andersen Construction is building the new two-story, 50,000-square-foot facility, designed by Bora Architecture & Interiors, at the northeast corner of Northeast Killingsworth Street and 42nd Avenue. After work wraps up, the old building will be demolished and replaced with a new 87,800-square-foot multifamily building .

But first, the remaining glulam beams and cross-laminated timber (CLT) columns and floor plates need to be placed. To piece together the timber frame, the team is using a new bracket system, Andersen Construction superintendent Ben Bentz said. He added that he hopes it鈥檚 used by the firm for all CLT projects in the future.

The metal brackets are fabricated onto the columns and at beams鈥� ends at the factory. At time of connection, the 3,400-pound beams are hoisted by a crane and slid into place.

A combination of two kinds of connectors 鈥� RICON and MEGANT 鈥� are being used, mainly because of cost considerations, Bentz said. A MEGANT can carry a heavier load, but a RICON is less expensive, he said.

RICONs are placed at columns鈥� ends on level two and have a little cup and a pin that sticks out when the other bracket snaps in. MEGANTs have in-and-out grooves that slide together and bolt down.

鈥淚鈥檓 going to push to use these connectors on any project I can because number one, they鈥檙e aluminum hot dip, so they don鈥檛 stain the wood; number two, they are available off the shelf; number three, they are just much simpler,鈥� Bentz said. 鈥淵ou don鈥檛 have to deal with lead times or any fabrication errors.鈥�

Crew members have only had to make a few field adjustments when the connectors are installed slightly off 鈥� maybe an inch 鈥� from what was planned, Andersen Construction project engineer Montana Maurice said. When that happens, she said, the connector is removed, placed in the correct spot, and any open drill holes are filled.

After the beams are placed, the floor panels can be installed. Each panel is 10 feet by 50 feet and weighs about 7,400 pounds.

Until most of the beams and floor panels are installed, the columns are essentially freestanding. The baseplates underneath, while embedded in the ground via a concrete foundation, are the only items keeping columns upright. They could tip over from a strong wind or accidental contact with a piece of equipment, Maurice said.

Right now, columns are gaining extra support from a heavy-duty brace typically used for concrete walls, Bentz said. However, the brace鈥檚 heft, Maurice said, can make it 鈥渁wkward鈥� and challenging to maneuver. Also, structural plans called for full-height (two-story) columns 鈥� adding to the difficulty of frame support.

Because of that and CLT being a relatively new material, Bentz said the team has had a hard time finding a brace strong enough to meet the engineering required and still be lightweight.

The wooden frame will be what people see when the building is complete, so Maurice said many precautions are being taken to not damage the material. Columns, beams and panels are being kept on slabs of plywood and off of potentially scratchy gravel. Also, protection boxes are placed around the columns to protect them from possible damage caused by gravel or concrete work.

The construction crew is about 40 percent done with the project, and on schedule to finish in August 2023. The timber frame should be complete this August, Bentz said.

The project is Andersen Construction鈥檚 11th mass-timber development. The firm has four more mass-timber projects in preconstruction, a representative said. A few of Andersen鈥檚 previous projects include 38 Davis and Sideyard in Portland and Oregon State University鈥檚 Peavy Hall replacement in Corvallis.