The Rock

It is an inescapable fact that the entire construction industry is built around one core product . . . .    the ROCK.

Perhaps with vivid imagination this occurrence could be traced back to the initial realization that, "Hey, this cave makes a more suitable dwelling than that tree," followed closely by, "There is just never a cave around when you need one." Whatever the case, since the dawn of construction this tradition has remained a constant theme throughout its progression.

This fundamental element of the industry is widely acknowledged, probably because indoctrination to this information occurs early on in one's life. Few can escape the lesson of the "Little Pigs" who opt for inferior construction materials and suffer cruel fates. However, as generally as the premise is accepted, it is just as widely taken for granted. Even by most of its participants, the construction process seems to be visualized as beginning subsequent to the delivery of aggregate. Without it, the process would not occur at all.

It all begins with the cold, hard fact that mother earth can supply the materials to create a demanded product and sustain an inventory for hundreds of years. This is literally mass production at its most primitive level. These products have no components (properties and characteristics yes, but components no) - size, cleanliness, and mix ratio are the important considerations here. Blow it, load it, crush it, screen it, load it again and move it out; that is the way it goes around the clock, six days a week or more.

Realizing this, it becomes possible to entertain the prospect that millions of dollars are spent to purchase (and considerably more maintaining) the equipment for the sole purpose of handling a payload valued at less than six dollars a ton. The bottom line here is volume.

With some kind of aggregate product being used in every construction project, it's easy to recognize and quickly understand the concept of volume. In the United States, the demand for crushed stone has reached an overwhelming 1.5 billion tons per year. That translates into approximately seven tons of rock produced and shipped for each person living in the U. S. - that's alot of rock.

Wade Sand and Gravel Company, of Birmingham, Alabama, is one of the area's largest crushed stone producers. Company president Robin Wade III credits the prime location of his operation with much of its success over the past five decades. They are in a somewhat unique situation. In addition to having a couple of asphalt plants on-site, they face a mountain of limestone on one side of their quarry and a mountain of Dolomite on the other. This is particularly beneficial considering that Birmingham's remaining steel industry is still only a stone's throw away, so to speak.

Vulcan Materials Company, the nation's largest producer of construction aggregates, produced approximately 136 million tons last year. Crushed stone accounted for 129 million tons of the 1995 total. Vulcan also operates three of the top fifteen producing plants in the country. How long can this continue? At the current production pace, Vulcan estimates that their quarry operations have an average life expectancy of more than 60 years from today.

Upon visiting several quarry operations, one of the most remarkable (and almost unbelievable) things that we noticed almost immediately was the durability of the actual crushing and screening equipment. These machines take the constant pounding produced by millions of tons of hard, abrasive rock and seem to last forever. In fact, several of the quarries were operating the same machines that have been in use for nearly 40 years.

Vulcan's Calera, AL quarry operation, one of the state's largest producers, is one such site. According to plant manager Joel Price, although many major components of the facility have not been significantly updated since the 50's, they produce over 2-million tons per year. If all of that rock, crushed into a size that was no bigger than a nickel in diameter, were shipped by rail in 100-ton hopper cars, it would take a train over 180 miles long to facilitate its transport. Price says that the operation was state-of-the-art when it was built and exemplifies the way quarries have run for the past few decades.

The earth covering the limestone, in this case, is removed and can be sold for filler dirt, screened for top soil, or simply moved out of the way for the time being. Holes are drilled in the limestone and then packed with explosives. The detonation or "shot" transforms the mountain of solid rock into a pile of limestone rubble. Using a loader, the pieces of the crumbled mountain are piled into trucks and hauled to the primary crusher. There the stone is crushed, in some cases from as large as 60 inches in diameter to a size of 10 inches, so it can be easily transported to the next phase of the process.

The rock then travels to the secondary crusher on a conveyor system. Here it is reduced from the 10-inch size to a size of around 3 inches. Any pieces that do not make it through the screen the first time are fed back into the crusher for another run. The smaller-sized stone then goes through its crushing and screening process and is made into one of the sixty-two products of the quarry. That is, if it passes all of the quality assurance tests.

Price, who dubs the Calera plant as the "Burger King of Rocks" (where customers get it their way), believes one asset of his quarry is its proximity to the rail system. Rail has historically been the way 70% of the site's stone was transported. With an increase in the local construction market last year, this figure is currently at approximately 55%.

Price also says that in the future various types of conveying systems may be used to move material from place to place on the site and offset the high expense of the equipment necessary to accomplish this today. Not to imply that today's equipment is not getting the job done. In fact, the quarry's primary loader was actually purchased in 1984 and has since served over 40,000 hours of service. This loader, however, will be seeing a little lighter duty as its replacement was being assembled during our visit.

The low cost of raw materials (when compared to refined goods) shows the importance of cost control in quarry operations. That's where modernization enters the rough, raw world of rock production. Even though the basic production process is the same, advancements in the machinery and computer technology allow the newer plants to produce the same amount of product much more efficiently.

For example, Vulcan's Huntsville, AL quarry produces roughly the same amount of stone as the Calera plant, but it was modernized about 8 years ago. Now, it can hold its production costs down. According to Ray Greene, Vulcan Material's area production manager, the implementation of the "Huntsville" technology could realistically lower the Calera plant's production costs by as much as 50-70 cents per ton. The variance in cost reduction is due largely to the difference in terrain and method of transportation.

The most apparent difference computer technology makes is in the product mixing processes. The updated technology allows Steve Greer, Huntsville's plant operator, to change the percentages of a product being mixed by simply keying into a computer that controls the mixing blends. Percy Eaton, Huntsville plant manager, says this new process is much better than swapping out the screens as it was done in the past. "I think this system also helps our product's quality. With more contractors working on performance-based pay scales and more checks by Department of Transportation (DOT), quality control is a big aspect of our business." Eaton also tells us that he is already looking into the future of his quarry and hopes to update it again within a couple of years.

A glance into the future of this industry, through the eyes of its leaders, reveals a continuing effort toward quality assurance. As these trends continue, the installation of specialized equipment will be necessary at the quarries. These plants will also be able to produce fractionalized sizes. Individual sizes reduce segregation in stockpiles and allow materials to be blended for specific requirements. Tunnels will be incorporated into the design of the plants to move the fractionalized sizes.

Such a transport system would allow the loading of asphalt plants from stockpiles, eliminating the need for loadout and inventory storage. Understanding that clean, dry, precisely-sized stone will be more costly to produce and for purchase, modern plants should be designed to effectively wash and handle the material in a manor that creates a minimum number of fines.

Current quarry sites will transform into what some have called "industrial centers for construction aggregate users". These sites will have (in addition to the quarry itself) asphalt plants, ready-mix, block and pipe, and pre-stressed concrete facilities at one location. These other plant operations may or may not be affiliated with the quarry. In fact, some plants have already been located at many quarry operations.

These measures are aimed toward an ultimate goal of achieving the highest quality product attainable at the lowest possible production cost. According to Robert Mayville, senior vice-president of Vulcan Materials, accomplishment of this will require an open line of dialog between the contractor and the stone producers, "We can only respond to each other's needs if we know what those needs are, and if we are willing to work together and communicate to fulfill those needs."

Industry experts note another emerging trend. Beginning as regional alliances, symbiotic networks will lay the groundwork for an industry-wide objective - Partnering.

The construction aggregates industry is making a concerted effort in a number of areas to overcome the perception of being just a place that makes alot of dust and noise while producing rock. The realization that their future success depends upon the stewardship of a company with respect to safety, health, environmental issues and community relations is being widely accepted. Therefore, sustaining the safety of personnel and ensuring a sound environment for the future has become the highest of their priorities.

Becoming a "good neighbor" through activities in civic and community organizations is a large part of the industry's relationship building. Creating places such as public parks, recreational sites and natural wildlife habitats with land preserves is the way some companies have become more interactive with their communities.

As companies and industries posture themselves for reaction to the increasing regulations and demand for total quality that business in the twenty-first century will undoubtedly require, the exchange of information will play a vital role. The mutual realization of construction-related goals will only be facilitated by an enhanced familiarity with inter-operational procedures. The first participants to adopt this approach will be the first to reap its many rewards.

Echoing this theme, Vulcan's Mayville eloquently noted, "Our world is constantly changing. Business conditions, technical specifications, and the competitive environment are all in a state of flux. In addressing these conditions, some will lead the way and some will follow. But if you're not willing to be the leader, or at least a follower, then you better get out of the way of those willing to do it. Because if we don't create the future, who is going to create it?"

© 1995, CONSTRUCTION MONTHLY/Franklin Publishing, Inc., All Rights Reserved