The Compaction Road

July 1, 1999
What are the most important developments and improvements in compaction equipment in recent years, in your product line and in the industry as a whole?John

What are the most important developments and improvements in compaction equipment in recent years, in your product line and in the industry as a whole?

John Burks, Benford America, Texas City, Texas: Overall increased consideration of operator comfort and ergonomic design. If the operator is not comfortable or at ease operating the machine for long periods, complaints will surely result.

Every Benford roller has been carefully designed from the seat to the 6-in-1 operations control lever.

Peter Price, Bomag Light Equipment Division, Binghamton, N.Y.: Compaction equipment manufacturers have focused their development in recent years on ergonomics, serviceability, safety and a more efficient use of technology.

In its heavier equipment, Bomag has developed compaction-metering systems that are incorporated into the equipment. Basically, these systems allow machines to tell operators when a required compaction density is reached. We are working on adapting these systems to our light line of compaction equipment.

Jack Pink, Dynapac, Schertz, Texas: My view is limited to light construction equipment. The single most important development and improvement in light compaction equipment in recent years is the introduction of the four-cycle gasoline engine into the rammer market. Regulatory agencies worldwide are focused on the reduction of noise and emissions in all small engine-powered equipment. Until 1996, when the four-cycle rammer was introduced into the U.S. market, the only true alternative available to reduce both noise and exhaust emissions in rammers, and at the same time eliminate fuel-mixing problems, was the diesel-powered rammer.

Once engine manufacturers developed the methods to ensure proper engine lubrication in severe vibration applications, the rest was relatively easy. It became a matter of adapting the heavier engine without compromising overall weight, balance, speed, compaction effort and reliability. The four-cycle engine-powered rammer has effectively reduced noise, emissions, fuel-mixing problems and maintenance.

Frank Multerer, M-B-W Inc., Slinger, Wis.: The recent trend has been to lighten the weight of portable equipment, especially rammers and plates, and to promote the lighter weight equipment as beneficial in terms of operation and productivity. The trade-off is simply improved portability at the expense of energy delivered to the soil - mass is a critical factor in the compaction equation.

M-B-W's EXA series of vibratory wheel compactors reduces equipment costs and maintenance. Removing personnel from the trench during the backfilling and compaction processes enhances safety. M-B-W's second major improvement is the soil compaction meter. Renters of rammers, plates, pogo sticks and trench rollers are often uncertain if they have achieved maximum compaction results under the conditions they are working. The SCM solves the problem by signaling operators when they have achieved it.

Steven Spence, Multiquip Inc., Carson, Calif.: The industry continues to demand compaction equipment that offers more technology, convenience and performance. Multiquip offers several compaction products to keep pace with these demands, including oil-injected rammers, which eliminate the need for mixed fuel and reduce maintenance.

We rounded out our compaction line further with four-cycle and diesel-engine rammers. Features such as remote control, four-stage air filtration systems and improved durability also satisfy current demands.

Dale Starry, Rand Equipment Division of Ingersoll-Rand, Mocksville, N.C.: Soil compactors, particularly vibratory soil compactors, have benefited from improved component technology, which has increased the products' reliability and reduced maintenance and repair costs.

Lighter weight machines have more powerful vibratory drums, greater drum amplitude and greater centrifugal force for more rapid compaction to the high-densit y requirements on aggregate, soil and mixed-material compaction projects. Machine features such as variable drum amplitude and variable vibration frequency work to match the natural resonant frequency of the material being compacted. High-mass/high-energy drums make quick work of densifying difficult-to-compact materials.

Compaction equipment designed for rolling hot-mix asphalt materials has seen even more improvement in recent years. Most vibratory compactors feature drums with variable amplitude eccentric designs; some models have as many as eight amplitude settings to provide flexibility in performance on a wide range of material types and layer thickness. Some machines provide automatic controls of vibration engagement, direction of eccentric rotation, and drum and tire water-spray systems operation. Machine performance can be enhanced by special night lighting packages, pavement edge-cutters and edge-rollers.

Chris Perkins and Kathy Reissig, Stone Construction Equipment, Honeoye, N.Y.: More attention is being paid to ergonomics when designing ride-on and handheld compaction equipment, including increased vibration isolation, added padded handles and adjustable handles. Comfort in the operator compartment is also important.

On many compaction products, you'll find LED lights for trouble-shooting, and diagnostic ports and computer chips for trouble-shooting and fine-tuning the machine's operation. Some compaction equipment includes compaction meters and laser- and global satellite positioning-guidance systems.

Jack Shewan, SuperPac Compaction, Cambridge, Ontario, Canada: The strong compaction market in recent years has allowed us to provide the market with soil machines that are easy to maintain and deliver higher and better performance in centrifugal force, maneuverability, travel speeds and increased usage of dual amplitude and frequency. This was all designed to reduce cycle times and ensure delivery, training or financing packages for rentals, leases, lease-to-own or outright purchase financing.

Tom Meyer, Vibromax, Racine, Wis.: In recent years, we have seen marked improvement in machine performance, particularly in the areas of centrifugal force, gradeability and maneuverability, while at the same time reducing overall machine dimensions.

Compaction equipment has become easier to maintain thanks to the implementation of lube-for-life technology, eliminating the previously labor-intensive need to grease the machine, often on a daily basis.

Mark Conrardy, Wacker Corp., Menomonee Falls, Wis.: Ergonomics is playing an important role in the design of handheld compaction equipment. Rammers are being designed with the lowest possible center of gravity, which provides ease of operation and maneuverability. Rammer and vibroplate guide handles are being geometrically redesigned for optimum balance and weight distribution. Re-engineered shockmounts have reduced hand/arm vibration significantly. This prevents operator fatigue.

In the rammer product line, noise reduction is being accomplished by using a specially designed cover that reduces noise transmission to the operator, along with a foam-filled ductile iron shoe to reduce shoe noise.

Environmental factors are another factor in compaction equipment. Wacker uses a variable spark-advance ignition system on its two-cycle engine rammers that automatically adjusts to the spark timing to match the engine load conditions, eliminating gas-rich emissions. Also, the carburetor-idle port injection eliminates buildup of fuel in the carb adapter at idle, which means less unburned fuel in the exhaust. Even the fuel cap is considered environmentally friendly because the design eliminates fuel from spilling while still venting fuel tank pressure.

What developments and trends do you expect to see over the next few years?

Burks: Very apparent is the continuing focus on the operating environment and serviceability of each machine. One particular trend we are seeing is that the list of available options is now on the decline in favor of being offered as standard equipment.

Price: The use of different materials, such as high-density plastics and specially formulated steels, and an increase in electronic control of compactor functions will become more prevalent in compaction equipment manufacturing in the next few years. Manufacturers will focus on maximizing compactor efficiency and simplifying operator controls to minimize operator fatigue.

Serviceability will be addressed in greater detail. Developments will allow operators and maintenance crews to electronically trouble-shoot and diagnose problems before they occur and eliminate time-consuming testing. Easy access to all of a compactor's replaceable parts will further simplify service and repair.

Bomag is developing GPS systems for large projects that could pinpoint areas that require additional compaction effort. Eventually, these systems could monitor a machine's functions in remote locations and trouble-shoot problems before they occur.

Pink: The focus must be on designing and developing systems and equipment that reduce overall costs to our customers. This focus would include the design of machines, so that they can be more efficient and environmentally friendly and require less maintenance and downtime. It will also include the development of interactive Internet programs for dealers and end-users that make it easier, more efficient and faster to do business and exchange information before, during and after the sale.

Multerer: Hand/arm vibration will join noise reduction as a major industry concern. The issue is red hot in Europe and will come to the United States. Style points will continue to get engineering attention. Fortunately, attention to maintenance should see renewed emphasis.

Expect to see a lessening dependence on evaluating soil compaction work only in terms of density and moisture content. Work is now in progress at a number of universities, state transportation departments and the Federal Highway Administration researching the concept of soil stiffness, which is said to be a superior engineering characteristic in terms of load-bearing strength. A conversion to stiffness evaluation could reduce soil-compaction expenditures by 10 to 30 percent on many applications, reduce the current tendency to over-specify density, yet improve long-term earth-work performance.

Spence: Manufacturers will be aware of environmental issues as they relate to machine operation and repair. Specifically, there will be efforts to reduce machine noise, emissions and vibration. I foresee a lot of advancement in the use of alternative materials to increase equipment durability and performance.

Starry: One of the major developments we expect in the next few years is the refinement of compaction-mounted material-density or stability-measuring devices. Several manufacturers now offer optional devices that will alert the compactor operator when to stop the vibratory compaction process and when further rolling provides no benefit.

Global positioning systems will further optimize the rollers' performance by keeping track of where the operator has achieved optimum compaction density and where additional rolling is still necessary to achieve minimum density requirements.

For compactors designed for hot-mix asphalt applications, automatic amplitude control devices may be a future technology to enhance machine operation. Compaction equipment manufacturers are evaluating technology as radical as waterless drums. Alternative technologies to vibratory drum rollers are being tested for possible utilization in the paving process.

Meyer: Many of the developments and trends in the construction equipment industry are cost-driven, with a growing focus on reducing the cost of acquiring and maintaining equipment, otherwise known as life-cycle cost. New technologies drive the trend toward reduced and simplified maintenance. By reducing or eliminating maintenance tasks, the operator, rental center and manufacturer will benefit from lower operating costs as well as fewer potential warranty claims resulting from improper maintenance. This will also lessen the burden on maintenance and service staffs, an area of concern in many dealerships and rental centers.

Conrardy: Ergonomic and environmental technology will continue to advance, as will designs to further reduce maintenance. Some of the unanswered questions regarding the two-cycle oil-injected and four-cycle models will be answered. At some point, there will be specific regulations for both noise and vibration, which will mandate even further reductions. These regulations appear now in Europe. The United States will be sure to follow.

What's unique about your company's product line?

Burks: We offer a comprehensive list of standard features as well as immediate delivery of machines in most cases. By offering each model with these standard features, our overall inventory can be decreased, which results in a faster shipping time because no add-ons are necessary. Benford America's goal is to continuously stock the most popular units, instead of building machines to order.

Price: Bomag's BMP851 multipurpose compactor has a self-diagnosing hydraulic system, and 90 percent of the unit's components are easily accessible for repair and service under swing-up or swing-out doors.

On the heavy side, Bomag's new 180 series rollers offer electronic steering and vibration functions. This machine can be driven facing either direction by one operator's swivel-sliding seat. When the operator turns the seat, the machine's electronic system senses the change and all of the controls switch themselves around so they respond as if the operator were driving in the forward direction.

The Variomatic compaction system, another Bomag innovation, automatically adjusts the unit's compaction force on the fly to meet any change in the material lift thickness, ensuring uniform compaction.

Pink: Dynapac produces one of the broadest ranges of compaction equipment in the world today, ranging from the 88-pound forward-direction vibratory plate, which produces 1,800 pounds of centrifugal force, to the world's largest double-drum ride-on vibratory roller, which weighs in at over 33,000 pounds and produces more than 42,000 pounds of centrifugal force.

Multerer: M-B-W's walk-behind trench rollers are the industry's only single-drum design - rubber-tired at rear - that matches or exceeds double-drum compaction capabilities, improves traction, lowers maintenance through superior isolation of vibration, and provides a design layout that is easily serviced.

Spence: Besides our own manufacturing, Multiquip has the flexibility to select compaction equipment from worldwide manufacturers. Our offering in the light to medium range is extensive. Coupled with this is widespread coverage with more than 70 field sales and service personnel, and the MQ Package, a total support concept for after-market sales support.

Starry: Some Ingersoll-Rand products are designed specifically for the compaction of aggregates, soils and mixed materials. Some models are specifically designed for the compaction of hot-mix asphalt pavements. A few models can perform both applications.

In the Ingersoll-Rand large double-drum vibratory roller line, primarily designed for compaction of hot-mix asphalt, a patented impact meter provides the machine operator with a visual reference to the correct speed for rolling with vibration, optimizing productivity. Drum water spray systems consisting of primary plus secondary water pumps, and spray bars, are unique to Ingersoll-Rand large double drums as well.

In the soil compaction line, variable-vibration frequency and dual amplitude enable the operator to adjust drum performance to the optimum levels of force for the material being compacted.

Perkins, Reissig: At Stone, we focus on the ergonomics of a product at the concept phase of development and continue to optimize the effort during the development of the product. An ergonomics engineer reviews operation, the position of handles and controls, and makes recommendations during the development of all our products.

The operator-friendly features of the Stomper and WolfPac lines are two examples. In addition, the Bulldog trench roller line offers a state-of-the-art radio frequency remote control that is powered by two household AA batteries and has an operating range of 100 feet. The small S20 forward plate features a fold-up handle for easy one-person transport in and out of trucks.

Shewan: Contractors know that they can count on SuperPac to deliver more compaction per pass, be light on fuel, provide superior gradeability, and now provide the operator with an ergonomically designed environment that gives him unparalleled visibility.

Chris Lynch, Vermeer Manufacturing Track Division, Pella, Iowa: We have designed our TC4A narrow-width trench roller specifically for the narrow-trench compaction market niche. The TC4A delivers 16,000 pounds of shaker force. The narrow and maneuverable unit is ideal for work with utility installations on golf courses and in residential areas.

The tamping wheel is extremely versatile, because it can be customized with four different widths up to 11 inches and fitted with either a sheep's foot or smooth pad. Our compactor is a true self-propelled unit, and the unique design allows it to be towed to and from jobsites, eliminating the need for a trailer.

Meyer: The Vibromax product line features machines that offer reduced and simplified maintenance and ease of operation.

The traction control system comes standard on all Series 5 rollers and allows the machines to handle grades up to 65 percent. The operator's platform on the Series 5 is common to all 20 models, allowing an operator trained on one machine to easily move to another without additional training. The Series 5 machines also feature a centralized hydraulic test station, greatly simplifying this critical maintenance task. An invisible yet valuable standard feature on all Vibromax ride-on rollers is a two-year parts and labor warranty.

Conrardy: Wacker rammers offer the WM-80 two-cycle engine, which was specifically designed to meet rugged rammer applications. Wacker rammers also feature an exclusive integral noise-reducing cover that lowers the amount of engine and shoe noise transmitted to the operator, and a shock-mounted handle that reduces vibration to the operator.

Ease of operation is another important feature. Just one lever controls engine starting, speed and stopping. A low center of gravity allows for a stable, easy-to-maneuver rammer. The large air filtration system is enclosed in the upper portion of the crankcase - protected from damage, but easily accessible for inspection and cleaning.

Wacker's vibratory plate series features a computer-designed baseplate with a tapered bottom and edges to give high speed, maneuverability and no-ridge asphalt finishing.

Wacker's articulated trench roller features a patented below-the-axle exciter system to send more vibration energy into the soil. The RT Series also features a new control system that combines both cable and infrared control in one control box. The infrared remote control battery charges while the box is connected to the machine via the cable, eliminating the need for separate battery chargers.