Roller-integrated compaction monitoring and assessment of high and low liquid limit silt subgrade using Green spline interpolation algorithm

The compaction quality plays a vital role in the long-term performance of highways, thereby making it an essential aspect. The prevalent approach for compaction quality control (QC) primarily depends on manual manipulation of compaction parameters during the construction process and sporadic testing after the completion. However, the former is greatly affected by human factors, while the latter method entails destructive detection, low efficiency, and fails to provide a comprehensive representation of the compaction state across the entire work area. This paper utilized roller-integrated compaction monitoring (RICM) technology combined with Real-Time Kinematic-BeiDou Navigation Satellite System (RTK-BDS). Initially, the compaction meter value (𝐶𝑀𝑉) and compaction power per unit volume (𝐸) were chosen as the real-time monitoring indexes for assessing the quality of compaction. Subsequently, a case study on the Hengyong Highway Project in China was conducted. The findings revealed that 𝐶𝑀𝑉 exhibits a stronger correlation with compactness, resulting in smaller data dispersion and higher data stability. Thus, this paper chose 𝐶𝑀𝑉 as the characterization index of the compaction quality of high and low liquid limit silt subgrade, and built a fast compaction quality assessment method based on 𝐶𝑀𝑉 and Green spline interpolation algorithm to obtain estimates for compaction quality on the entire work area, enabling QC of silt subgrade. The verification results validate that the proposed method facilitates a swift and uninterrupted evaluation of the compaction quality throughout the entire construction area. This serves as a fundamental basis for effectively preventing quality defects and enhancing the overall quality of highways.