Effect of compaction on physical and mechanical properties of solidified dredged materials

The compaction technology has been generally employed in solidification of dredged materials in China. The mechnical behavior of the compacted solidified dredged materials is urgently needed to be cleared. The dry density, California bearing ratio (CBR) and unconfined compressive strength (UCS) of solidified dredged materials under proctor compaction tests are examined. The test results show that there exists an effective compaction number. The compaction becomes invalid when it exceeds the number, and the density and the dry density of compacted soil are basically equal to those of solidified soil. The CBR of compacted soil can be calculated by that of solidified soil, and is about one tenth of solidified soil. The CBR of solidified soil is easy to meet the standard requirements of embankment whereas the compacted soil can not. The higher the UCS of solidified soil, the larger the UCS of compacted soil. However, the strength loss is also greater, i. e. the UCS of compacted soil is about one third to half of that of solidified soil. Accordingly, in the practical solidification of dredged materials, strong bonding cement, weak bonding quicklime or composite modified materials should be reasonably chosen.