Cranes lift 360 tons of bridge beams

It may not have been Dan Harmon's biggest "pick," but it certainly was one of the most visible.

Harmon Crane & Rigging of Kalispell helped pick up and set 360 tons of pre-stressed concrete beams this week, forming the underpinnings for the deck of the U.S. 93 bridge being built over Church Drive north of Kalispell.

Three of the 120,000-pound, 142-foot-long, six-foot-high beams went in on Tuesday.

After trucks turned around and returned from Billings with the last half of the load Wednesday night, three more beams slid into place on Thursday morning.

"It went pretty well," Harmon said.

Harmon had just hopped down out of the crane and eyed his wristwatch while watching his son Mike and another worker retrieve the timber blocking that supported the weight of the crane as it hoisted its load.

"Look at that - it only took an hour and 15 minutes this time."

Tuesday's crane work took a bit longer, but taught them some lessons on how to proceed Thursday.

He and Mike, who along with brother Chuck and his wife, Darla, gradually are taking over the family business, brought in their 100-ton hydraulic truck crane for last week's bridge work.

Harmon's crane worked in tandem with another 100-ton crane owned by Sletten Companies, the Great Falls contractor building the bridge. Sletten hired Harmon to supply the mechanical muscle on the other end of the beams.

In turn, Sletten was subcontracted by Knife River, the prime contractor for the Montana Department of Transportation's $6.2 million project: a mile-long, four-lane highway with grass median that includes the "junior interchange" over Church Drive north of Kalispell.

Junior interchange is the state highway department's term for what looks like half a cloverleaf. There will be two ramps from Church Drive to U.S. 93, both of them right-turn-in, right-turn-out.

One ramp will come off the two northbound lanes of highway traffic and circle beneath the bridge onto Church. The other ramp mirrors it from the southbound lanes.

It's the current phase of a multi-year highway rebuild from Kalispell to Whitefish.

Dean Sackett, engineering project manager for the state, explained the construction process.

This bridge construction started with earth berms, or "surcharges," piled along the highway for several months. Sackett said they compacted the soil, which sunk between seven and 17 inches before the berms were scraped away and the surcharge dirt went into building the west-side ramp onto Church Drive.

Bridge work started in late June, when crews started driving 132 pilings 70 or more feet into the ground and poured concrete abutments supporting both ends of each beam. They shut down Church Drive and excavated the road bed to pass beneath the highway.

The plan is to pave the ramp Monday and open it as a detour onto Church Drive, probably on Tuesday.

The two 100-ton cranes - Harmon said his crane used 45 or 50 feet of boom - maneuvered the beams over those abutments while workers on the ground directed the crane operators as they lined them up precisely over the pencil lines scribed across the concrete.

Harmon, who started his company as a one-man operation in 1982, has been in the Flathead Valley for 44 years and running cranes for 47 years.

He has cranes from 17-ton to 100-ton capacity, and has used them all on jobs from hoisting house trusses to installing massive air-handling systems.

"I tend to stay away from the big jobs now. We have so many customers that if we get tied up on a big job, I have to work," Harmon quipped.

He is, after all, semi-retired.

Harmon Crane & Rigging generally sets transformers for electric utilities, lift stations for sewer-system extensions and air-handling systems for sawmills. Just before the bridge job, Harmon set close to 50 truckloads of precast concrete for Plum Creek in Columbia Falls, hoisting 16-foot diameter pipe using 140 feet of boom.

"We're trying to stay on the bigger jobs now that there are so many smaller cranes elsewhere in the valley," he said.

"But there's times when we're not big enough, too. There's getting to be bigger and bigger bridges," he said. "Engineers design them without thinking about what's available to build them."

With almost five decades at the crane controls, Harmon has a pretty good handle on his company's capabilities.

"I know exactly what I want when it comes to cranes," Harmon said. He said this 100-ton Grove was manufactured in the United States and shipped to Belgium before its original purchaser realized that its 10-foot girth was too wide for the 8- or 9-foot maximum Belgian road width. Harmon knew its specifications, wanted it for his work and went to Belgium to bring it back home.

"We have several cranes, and all have a specialized use," he said.

"Anytime we make a large pick it takes a larger crane. If it has to go a longer distance it takes a larger crane yet. I know the chart [manufacturer's specs] and I know what I need."

Reporter Nancy Kimball may be reached at 758-4483 or by e-mail at nkimball@dailyinterlake.com