Assessment of Roller-Integrated Compaction Monitoring Indexes for Low-Liquid-Limit Silt Based on Roller Vibratory Acceleration Analysis

Roller-integrated compaction monitoring technology has been widely used in highway construction and has played an important role in controlling compaction quality and construction progress. In order to detect and assess the compaction quality of the subgrade accurately in real time based on the analysis of the acceleration signal of the vibrating wheel, a total of four real-time monitoring indexes, namely, peak value of acceleration (Ap), compaction meter value (CMV), root-mean square value of acceleration (Arms), and crest factor value (CF), were selected to characterize the compactness of the soil. To determine which of these indexes is the most appropriate, field compaction experiments under various rolling conditions were carried out on the fifth section of the Hengyong Highway in Hunan Province, China. The data of compaction parameters, compaction quality, and integrated compaction monitoring under various working conditions were collected and subjected to statistical regression analysis. On the basis of the time-frequency analysis of vibration response signals, the CMV could more accurately characterize the compactness of low-liquid-limit silt. In addition, the mapping relations between compaction quality index and roller-integrated compaction monitoring indexes were founded to define the control criterion of roller-integrated compaction monitoring index, namely, CMV, providing scientific guidance for making sure the compaction quality of the subgrade during construction.