Big blocks solve big problems

When most people think of a homecoming, they think of beautiful fall foliage, parades, and football games. For Bill Callow, president of Templar Technologies in Mt. Arlington, N.J., his homecoming to upstate Michigan was filled with clinker domes, big blocks, the reminiscent Lake Michigan wind, and a couple of problems, too.

While clinker dome could be slang for a football helmet and big blocks might have significant meaning on the gridiron for a homecoming football team, Callow was back in town for anything but a game. The Michigan Department of Environmental Quality (MDEQ) was threatening to throw a penalty flag on a clinker storage facility on the shore of Lake Michigan for which Callow was attempting to find solutions. Strong lake winds were finding their way into the open-sided domed structures built in the 1970s and causing unacceptable dust levels. Callow was called in to avoid serious consequences from MDEQ.

Clinker is unprocessed cement, usually consisting of as much as 80 percent limestone with sand and other materials mixed in. This is the major ingredient that makes up cements final recipe. The clinker was loaded into the tops of the domes by conveyer belt 115 feet in the air and reclaimed by gravity via clinker ladders. One can imagine the problems created by wind coming through the open areas between the columns supporting these domes.

These [domes] were steel structures roughly 225 feet in diameter and 115 feet tall, said Callow. And though they had columns every 30 feet supporting the structure, it was open. Clinker dust was way too prevalent.

Not only was the dust a concern, but also clinker was being lost because it was spreading out beneath the open domes. When exposed to the elements, valuable clinker can become contaminated or lost in run off. This run off itself can create serious problems as well. Clinker is highly alkaline and, if it gets into groundwater, it can make that water hazardous to life. And with Lake Michigan being adjacent to the facility, serious environmental concerns loomed.

We had two significant challenges, said Callow. First, the MDEQ needed the dust emission reduced. Second, the clinker was spreading out around the perimeter of the storage domes and was being compromised by exposure to the elements.

Project Manager Doyce Little also was concerned with the gradual erosion at the edges of the clinker piles. While we could reclaim some of this exposed material, when cement is worth $75 per ton, you dont want any clinker being lost to wind and rain, said Little.

As Callow and Little collaborated, they knew one of the options would be an earthen berm reaching to the suspended domes lower edge. The berm would have to be sufficiently wide at its base to extend 15 to 17 feet high. This would require a phenomenal amount of soil, but also had the drawback that the base of the berm would extend under the covered area of the dome.

The second solution involved a poured concrete wall. Callow and Little had little hope for this solution because each had experience with the potentially high cost and long construction schedule associated with this type of construction.

The big block solution

With months of construction time projected and millions of dollars in potential construction costs—as well as MDEQ fines—Callow was more than open to solutions that would cut both cost and construction time, as well as provide a remedy that would last for years to come.

Little and Callow listened to the possibilities for a Redi-Rock retaining wall described by Mark Manthei of MDC Contracting, of Charlevoix, Mich. Subsequently, Callow and Littles outlooks changed tremendously. First, Redi-Rock was the low-bidder, at less than one-half of other options. Second, because of the big blocks easy installation, the entire project could be completed in just a few weeks, not months, reducing the amount of lost clinker and satisfying the MDEQ concerns more rapidly.

We needed to do a couple of things to customize this solution, said Manthei. First, Callow decided that the wall would have to be vertical to make construction easier as well as to keep the whole wall structure under the covered area of the dome.

Most of the clinker material is handled by front-end loaders, said Little, so we needed a wall that could withstand the pushing and pulling pressures of heavy-duty machinery all the way up the vertical wall.

Manthei and Templar Technologies devised a way to tie the wall together vertically to withstand such pressure. A steel shaft was attached to plates underneath the bottom course of block, threaded through each block, and connected to another plate above the top course of block. This allowed the individual blocks to interlock horizontally—as they usually do—with the sheer knob system and vertically with the steel shafts. Front-end loaders would have to move the wall as a single unit (the entire weight and mass of the wall), as opposed to moving or dislodging a single block.

Installation

Despite their tremendous size and weight (2,500 pounds and 5.75 square feet of face each), Redi-Rock blocks are installed quickly and easily. More than 4,000 blocks were installed in less than one month. In total, 23,000 square feet of face were installed, sometimes at a rate of 400 blocks, or approximately 2,400 square feet, per day.

The installation process started with laying a 1-foot-deep foundation of 1-inch crushed stone. Then, steel plates were placed every 8 feet along the footing. Over these were laid the base course of Redi-Rock blocks and then 1-1/4-inch galvanized steel rods were threaded through the block (through 4-inch, plastic pipe that was cast into the blocks) and screwed to the steel plates. This sequence continued as the wall rose—place the blocks and thread in a section of rod. Finally at the top of the wall, steel plates were slipped over the rods and cinched down, tying the whole wall together. Upon completion, there were 2,000 blocks installed per dome and each wall weighed approximately 5 million pounds.

Entry portals were built out of the block, and custom blocks surrounded the columns inside the domes to protect them from potential front-end loader accidents.

Once the walls were constructed, steel angles were installed along the top row of block and metal sheeting was applied to create a nearly dust tight environment. The difference in the clarity of the air inside the facility once construction was done was tremendous, said Little. And I knew I wasnt going to have any problem with these walls going anywhere. 

Conclusion

We treat every project like a new opportunity to showcase the versatility of the product, said Ben Manthei, managing partner of Redi-Rock International. Less installation time, less cost, and more durability, all without sacrificing aesthetics, isnt a tough story to tell.

And for someone who looks forward to his homecomings in the beauty of the North Michigan landscape, Callow can rest assured that his efforts played a small part in keeping it that way. hen most people think of a homecoming, they think of beautiful fall foliage, parades, and football games. For Bill Callow, president of Templar Technologies in Mt. Arlington, N.J., his homecoming to upstate Michigan was filled with clinker domes, big blocks, the reminiscent Lake Michigan wind, and a couple of problems, too.

Scott Smalstig is president of Joseph David Advertising and can be reached at ssmalstig@jdausa.com. For more information on Redi-Rock, contact Ben Manthei at 1-866-222-8400, or go to www.redi-rock.com for design, construction, and engineering information.