Experimental Study on the Compaction Characteristics and Evaluation Method of Coarse-Grained Materials for Subgrade
Shanzhen Li1, Yangsheng Ye2, Liang Tang1
1School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China.
Materials (Basel, Switzerland)
|November 27, 2021
Summary
Compaction meter value (CMV) effectively monitors railway subgrade compaction. Over-compaction can degrade material, highlighting the need for optimized roller passes in construction.
Area of Science:
- Geotechnical Engineering
- Transportation Engineering
- Materials Science
Background:
- High-speed railway construction demands stringent quality control for coarse-grained materials.
- Understanding compaction characteristics is crucial for ensuring subgrade stability and performance.
- Traditional in-situ tests have limitations in real-time compaction assessment.
Purpose of the Study:
- To evaluate the effectiveness of roller-integrated compaction measurements (CMV) against traditional methods.
- To assess the stability and spatial uniformity of subgrade compaction.
- To determine an optimal target value for CMV in railway construction.
Main Methods:
- Conducted a field compaction experiment on a subgrade near Bazhou Station, Beijing-Xiong'an Intercity Railway.
- Compared compaction meter value (CMV) with plate load test, light falling weight deflectometer test, and shear wave velocity test.
- Utilized a proposed 'δ' criterion for CMV stability analysis and geostatistical analysis for spatial uniformity.
Main Results:
- Compaction parameters, including CMV, initially increase with roller passes but can decrease with excessive effort (decompaction).
- CMV demonstrated less variability compared to the elastic modulus from the plate load test (Evd).
- The proposed stability analysis method effectively quantifies acceptable compaction percentages.
Conclusions:
- Roller-integrated compaction measurements (CMV) offer a reliable method for monitoring subgrade compaction.
- Geostatistical analysis is valuable for assessing the spatial uniformity of compaction.
- The study provides a practical reference for optimizing geo-material compaction control in transportation projects.
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