Intelligent Compaction Measurement Value (ICMV) is a generic term coined by the US Federal Highway Administration (FHWA) for a calculated value based on accelerometer measurements on IC vibratory roller drums. ICMV is a current compaction quality control metric and technique that can cover 100 percent of the compacted area. Therefore, IC and ICMV can be used to improve quality monitoring and control and push roller technologies’ enhancements.
Levels of ICMV
The following describes the “Levels of ICMV” for the systematic classification of ICMV. The classification is based on four criteria: (1) correlation with material’s mechanical (modulus) and physical properties (density), (2) validity during decoupling when a drum loses contact with a compacted body, (3) capability to allow performance analysis of the compacted body, (4) applicability to obtain layer-specific mechanical and physical properties of compacted body, (5) capability to be enhanced by advanced technology such as AI. This lays out the road map for past, present, and future ICMV development.
- Level 1 ICMV – Empirical Solutions based on Frequency Responses: The Level 1 ICMVs are empirical solutions based on frequency responses represented by harmonic ratios. It is computed based on the Reactive Model for Vibratory Compaction or Reactive Model for Oscillation Frequency Reactive Model.
- Level 2 – Energy and Rolling Resistance Solutions: The Level 2 ICMVs are energy and rolling resistance solutions. It is computed based on Reactive Model with Rolling Resistance for static compaction.
- Level 3 – Simplified Static Mechanistic Solutions: The Level 3 ICMVs are simplified static mechanistic solutions. It is a static solution based on Discrete Vibration Model, Steel Drum Movement Model, or Continuum Static Model.
- Level 4 – Hybrid Model with Dynamic Mechanistic Solutions: The Level 4 ICMVs are dynamic mechanistic solutions with hybrid of various mechanistic ICMV models.
- Level 5 – Dynamic Mechanistic and Artificial Intelligence Solutions: The Level 5 ICMVs are a combination of dynamic mechanistic solutions and artificial intelligence solutions.
Notes:
1. Correlation: The threshold value for coefficient of correlation between ICMV and in-situ spot tests is generally accepted as R = 0.70 or R = 0.5.
2. Decouple: Produce valid solution of ICMV during double-jump or decouple when the roller drum and compacted material lose contact.
3. Layer Specific: Produce layer-specific ICMV values.
4. Advanced IC: The ICMV can be combined with advanced technologies such as Artificial Intelligence and auto-feedback controls.
4. X: No or Bad, O: Satisfactory, ?: Unproven; V: Yes or Good.