Experimental study on the influence of subgrade moisture content on compaction quality control indexes
Hui Zhao, Huaiping Feng, Jianmei Chang
Abstract
Intelligent compaction (IC) technology, which is based on the relationships between the subgrade stiffness properties and intelligent compaction measurement values (ICMVs), has been widely used in the compaction quality control (QC) of subgrade construction. The influence of moisture content (MC) on the stiffness properties is significant and well known but is often ignored in the current practice of IC. In this study, the relationship between the vibration compaction value (VCV) and subgrade reaction modulus (K30) considering the influence of moisture content is investigated. The results show that the influence of MC on quality control indexes gradually becomes significant, especially in the later stage of compaction. Furthermore, K30 is more sensitive than the VCV to moisture content, which means that the influence of MC is easy to ignore when taking the VCV as the ICMV. Finally, the specified VCV should be obtained when the MC is on both sides of the optimum moisture content (OMC) to ensure the accuracy of the QC of compaction.