Contrastive analysis and test study of compaction standards used in China and Germany

This paper introduced the quality control and quality assurance tests used during high-speed railway subgrade construction by China and Germany. Through laboratory Proctor compaction tests and in-situ tests using two kinds of filling materials, the correlations between compaction grade used in China and Proctor density used in Germany are obtained. The relations among the porosity, compaction grade and Proctor density are analyzed, and reasonable controlling indexes for porosity used in the high-speed railway for middling grained and coarse grained soil are put forward. The different stiffness coefficients for the subgrade are studied by field tests through the plate load tests, and the relation between them is obtained. Finally some suggestions on compaction quality inspection of subgrade and embankment are proposed.