Sakai Heavy Industries has upgraded its Compaction Information System (CIS) to the "CCV-Plus" generation, factory-installed on the newly launched SV544-1 series 84-inch vibratory single-drum soil compactors. In highway base course construction, the stiffness of the laid aggregate changes not only with depth but also with temperature, because hot asphalt-treated base (ATB) materials become progressively stiffer as they cool. A roller that applies the same vibration amplitude to a 140°C hot zone and a 60°C cooling zone will over-compact the hot, soft material and under-compact the cold, stiff material, producing a structurally non-uniform base layersakaiamerica.com+1.
The CCV-Plus system couples two previously independent sensor streams into a single closed-loop control. The engineering core is the "Compaction Control Value (CCV) Sensor," a dual-axis accelerometer mounted on the drum bearing housing that measures the rebound acceleration waveform after each impact. The CCV algorithm extracts the second-harmonic component of the rebound wave, which correlates directly with the dynamic stiffness modulus of the underlying material. This is paired with a forward-looking "Infrared Surface Temperature Sensor" scanning a 2-meter swath of the mat ahead of the drum. The breakthrough innovation is the "Temperature-Viscosity Compensation Map" stored in the ECU. The controller correlates the measured CCV stiffness against the surface temperature and computes a "true" structural stiffness value that is independent of the thermal state of the material. This prevents the system from falsely reporting high compaction on hot, soft material where the drum penetrates deeply (generating a high rebound reading that does not reflect actual density).
The system feeds this corrected stiffness value back to the "Eccentric Force Modulation Valve." When the roller passes from a hot zone into a cooling zone where the stiffness reading is genuine, the controller increases the centrifugal force by 15% to drive the aggregate into a tighter matrix; when re-entering a hot, soft zone, it reduces the amplitude to prevent aggregate crushing and surface waviness. All position, CCV, and temperature data are logged via the integrated GNSS module and exported through the AithonMT software for post-project documentation, satisfying DOT and FHWA acceptance reporting requirementsconstruction. Field validation on a 14-kilometer interstate widening project demonstrated a 22% reduction in non-uniform density penalties and eliminated the need for follow-up density core sampling on 80% of the placed length.
