Climax Molybdenum Mine – Ore Bulk Storage – United States

Scope of Work

Dome strength provides support for conveyor system, snow load in Colorado

Climax Molybdenum needed ample storage at its Leadville, Colorado, mine, but there was a catch: In effort to make this project economically feasible the new structure had to utilize an existing conveyor system and be robust enough to hold the weight of the conveyor, headhouse, and the expected snowfall.

After seriously considering another type of dome, a monolithic concrete dome from Dome Technology was selected based on strength and serious construction savings.

A dome capable of storing 130,000 metric tons was built to accommodate an existing conveyor system, which was reassembled to feed directly into the apex. Based on the dome’s geometry, the apex was capable of bearing the weight of conveyor systems and headhouse.

Cost savings, then, were twofold: The customer reused an existing conveyor system, and additional costly support systems are not required to share the load. “Utilizing the existing equipment yielded tremendous savings for the customer,” Dome Technology project superintendent Brent Hardy said.

The dome’s strength provided another advantage.  The weight of the conveyor and accompanying headhouse could easily be supported on the apex of the dome. Additionally, with its location in a snowy clime, the structure was engineered to surpass a snow load of 5.27kN/m2 (110 PSF) while supporting the apex mechanical load. A different type of storage facility could not support a similar load on its own.

“It’s very difficult to find a storage building that can bear the weight of the snow load and the conveyor load at the same time, but the dome can accomplish that,” said Dome Technology Vice President of Operations Dan South.

The project came with other challenges too. At an elevation above, 3353 meters (11,000 feet), weather conditions suitable for building would last just four months in the calendar year; since a dome’s rapid construction process is ideal for quick construction, project managers and crews maximized workdays to expedite construction and complete the job within the amount of workable time.

Dust control was an also a concern, and the dome’s seamless storage capabilities would easily contain the product, reducing dust throughout the site and the minimizing the environmental impact too.

With a 101 meter (330-foot) diameter dome completed in short order, the result was a dome meeting the customer requests. Everyone including the construction crew was happy with the outcome. “That was a great project—it went really well, and everyone on the crew would go back there and work in a heartbeat,” Hardy said.