''Bomag's Terrameter and Compaction Management Systems have for years set standards in compaction control and are in widespread use on earthworks applications as well as on general highway and transportation engineering projects,'' says a company spokesman. ''The new innovations further strengthen Bomag's image as a pace-setter.''

Terrameter BTM-E

"With the new BTM-E measuring system for Variocontrol single-drum vibratory rollers, a direct, physical measurable variable can be determined for the first time," the spokesman says.

"Using the interaction between the load applied to the soil by the vibratory roller and the resulting soil deformation the dynamic stiffness modulus EVIB (MN/sq m) is mathematically determined and displayed in an analogue form. EVIB has a direct correlation with the deformation module EV1 or EV2, and CBR so that the compaction specification and the results can be directly displayed.

"In contrast to the familiar Omega value, the new EVIB value is independent from the parameters of the roller. The amplitude has therefore no influence on the result."

The BTM-E system is available on Bomag Variocontrol single-drum vibratory rollers. A special feature is now also available: five EVIB values (45, 80, 100, 120, 150 MN/sq m) can be pre-selected as target results by the roller operator.

Asphalt Manager

The Asphalt Manager for Variomatic tandem rollers uses a totally new method of stiffness calculation on asphalt.

''Asphalt Manager automatically measures and controls the compaction performance of the roller. Thus maximum roller performance is achieved continuously. Asphalt temperature is constantly measured and incorporated into the management system. The increase in compaction can be monitored by the roller driver using an analogue display,'' the spokesman says.

''Measurements show that the dynamic stiffness calculated by the Asphalt Manager EVIB [MN/sq m] can be used as a measure for the level of compaction given uniform sub-base stiffness and taking into account the influence of temperature.

EVIB and Marshall density are directly related to each other. The Asphalt Manager thereby improves asphalt compaction and surface quality.

Compaction Control with GPS

The Bomag GPS system with PC, with touch-screen facilities and specially-developed software is available on singledrum vibratory rollers and Variomatic tandem rollers with the Asphalt Manager.

''With the GPS system, the position of the roller is accurately documented. This is particularly useful on large-scale projects such as highway, railway, airport, dam and landfill construction where the positioning of the roller depends on the skill and concentration of the roller driver,'' says the spokesman.

''The benefits of the GPS system are available to site management with responsibility for quality assurance, assistance for the operator in monitoring the rolling pattern, corrective information when leaving track alignment and precise co-ordinate related documentation of the compacted areas.

''The tracking of the roller is achieved by use of differential GPS technology, that is with a mobile GPS receiver on the roller and stationary reference receiver.

''The results of compaction control Omega or EVIB are clearly shown alongside the roller position. The roller driver can monitor the result online on a colour display in the cab.

''The BCM-GeoCAD software, which has been specially developed for compaction equipment, offers comprehensive analysis and recording capability.

''The Bomag GPS System offers the most economic and reliable method for compaction and quality assurance on soil and asphalt.''