Individual penetration of aggregates into soft seabed and the effects of geosynthetics

摘要

The construction of structures on soft seabeds can pose major problems due to the very low bearing capacity of some marine deposits and the problems caused by the penetration of individual aggregate/rock particles into the seabed. Even when the overall bearing capacity of the marine seabed is adequate, a geosynthetics layer might still be required to prevent the penetration of individual aggregate particles into the seabed. A research programme has been undertaken to study the penetration of aggregate, used as embankment material, into soft marine deposits. Included in the research was the development of a new test procedure to determine the susceptibility of aggregate penetration into the seabed. The results of the research show that the size of aggregate and the presence of a geosynthetic are important parameters in controlling the penetration of aggregates into the seabed. The results of tests using different geosynthetic materials show that non-woven or woven geosynthetics perform better than geogrids. For the cases without a geosynthetic layer, an empirical curve is presented to correlate the height of embankments, liquid limit of the marine deposits, aggregate size and its penetration into the seabed.