Pseudo-solidification of dredged marine soils with cement - fly ash for reuse in coastal development
The dislodged and removed sediments from the seabed, termed dredged marine soils, are generally classified as a waste material requiring special disposal procedures. This is due to the potential contamination risks of transporting and disposing the dredged soils, and the fact that the material is of...
Saved in:
| Main Author: | |
|---|---|
| Format: | Article |
| Published: |
World Scientific & Engineering Academy & Society, WSEAS (USA)
2015
|
| Subjects: | |
| Online Access: | http://www.wseas.org/wseas/cms.action?id=10179 http://www.wseas.org/wseas/cms.action?id=10179 http://eprints.uthm.edu.my/7422/1/chan_chee_ming_6_U.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The dislodged and removed sediments from the seabed, termed dredged marine soils, are
generally classified as a waste material requiring special disposal procedures. This is due to the
potential contamination risks of transporting and disposing the dredged soils, and the fact that the
material is of poor engineering quality, unsuitable for usage as a conventional good soil in
construction. Also, taking into account the incurred costs and risk exposure in transferring the
material to the dump site, whether on land or offshore, it is intuitive to examine the possibilities of
reusing the dredged soils, especially in coastal development where the transportation route would be
of shorter distance between the dredged site and the construction location. Pseudo-solidification of
soils is not a novel idea though, where hydraulic binders are injected and mixed with soils to improve
the inherent engineering properties for better load bearing capacity. It is commonly used on land in
areas with vast and deep deposits of soft, weak soils. However, to implement the technique on the
displaced then replaced dredged soil would require careful study, as the material is far more poorly
than their land counterparts, and that the deployment of equipment and workforce in a coastal
environment is understandably more challenging. The paper illustrates the laboratory investigation of
the improved engineering performance of dredged marine soil sample with cement and fly ash blend.
Some key findings include optimum dosage of cement and fly ash mix to produce up to 30 times of
small strain stiffness improvement, pre-yield settlement reduction of the treated soil unaffected by
prolonged curing period, and damage of the cementitious bonds formed by the rather small dosage of
admixtures in the soil post-yield. In short, the test results show a promising reuse potential of the
otherwise discarded dredged marine soils. |
|---|