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Part of the road running along- side the Rhine River, was in need of re-construction. As a result of increased traffic and axle loads, crocodile cracks and deep lane grooves became clearly evident. Originally, it was thought that only the wearing course was in need of repair. However, after milling the first layer, it was clear that the bearing capacity of the existing base course was not strong enough to carry further traffic. At that point, the project took a turn, needing to be fully milled: base course, binder, and surface course. What was thought to be a small job, turned in to a much larger asphalt construction project. After stabilization of the sub-base, the new construction began.
The asphalt base course was finished, and the BOMAG BW 154 AP-4, one of the most commonly used rollers in Germany, compacted the binder layer and surface course. One of the rollers was upgraded to the MCA 3000, prepared with GNSS positioning, a stiffness measurement, and temperature sensor. The BOMAG roller itself, was equipped with the original Asphalt Manager System. Therefore, our results could be compared with the BOMAG system, one of the most-used systems on the market. The BOMAG roller was not equipped with a positioning system.
Technical Data BW 154 AP-4 AM
Exciter System
Frequency ..........[Hz] 45/45
Amplitude .......... [mm] 0.66/0.32
Weights
Operating weight CECE w. ROPS-cabin [kg] 7,300
Axle load, front / rear CECE.....................[kg] 3,750/3,550
Static linear load, front / rear CECE ...... [kg/cm] 25/23.7
Gross weight ........................................... [kg] 8,800
Upgrading the BW 154
Display
Display installation into the cabin.
MCA 3000 display mounted next to the BOMAG dashboard.
Acceleration Sensor
Next step was to install our MAS180 vibration sensor onto the vibrating drum. With a bracket on the drum drive motor, the fixation was an easy task.
Acceleration sensor on the vibrating drum. (front)
Temperature Sensor
The additional temperature sensor was easily mounted with a magnet onto the machine. The sensor was placed between the drums to have similar conditions on the mat, during the measurement of surface temperatures.
Temperature sensor positioned next to the center of the roller.
Positioning Sensor
As the last step, the GNSS antenna was placed on top of the cabin. As a standalone machine, there was no need for a high precision GNSS, nor exact placement on the roller.
SBAS GNSS antenna mounted on top of the cabin.
After the final installation, a compaction test was completed to define the target ICV-value. Density-values, determined with the Nuclear Sensor have been compared with the ICV-values and the Evib-values from BOMAG. As a result, the target value was set at 60 on the display, and compaction began. With the help of the MCA 3000, a new chapter in compaction was opened. Compaction carried out with the MCA 3000, guaranteed proper and homogenous compaction of HMA, without highly sophisticated and complicated equipment.
The operator concluded: an ease of use, the added value of information displayed on the screen, and an increase in productivity from the display position of the machine, aiding in the reduction of operating cost.
Views (screen shots) can be selected by the operator, adjustable to fit the need:
Left: Compaction passes mapped. Right: Temperature of asphalt mat.
Left: Actual ICV-value. Right: Passes with Vibration.
Left: Actual ICV-value. Right: Deviation of ICV-values from pass to pass.
Provided on the display, is information necessary for excellent compaction. After job completion, a report is generated on a PC without additional software: easy, quick and efficient.
The BW 154 with a pneumatic tired roller (in front), used for pre-compaction.
