Methods for improvement of clay slurry or sewage sludge

Abstract

Clay slurry or sewage sludge may be used as fill materials for land reclamation. However, the treatment of very soft materials of high water content is difficult. One major difficulty is how to create a working platform on top of the slurry layer for required soil improvement works such as vacuum preloading to be carried out. Several methods that can be used to create a working platform on top of a slurry layer are reviewed in this paper. These include (1) sun drying; (2) capping with sand or other good soil; (3) use of geotextile; (4) cement mixing; and (5) dewatering using drainage. The advantages and disadvantages of each method are elaborated. Practical examples are given to illustrate the application of some of those methods. Sewage sludge is more difficult to treat because of its organic content and a combined chemical and mechanical method needs to be used. Two conceptual methods for using sewage sludge and other waste materials for land reclamation are also proposed.

Potential of Flocculant-Aided Soil Slurry Dewatering in Land Reclamation: Laboratory Investigations

“…To cater the industrial and urban development, large-scale foreshore land reclamation projects have been taking place in coastal regions in many East Asian countries. In the engineering practices in China, seabed soils are widely used as fill materials in land reclamation projects [1]. Seabed soils are easily obtained at coastal regions.…”

“…Two techniques are usually used for the dewatering of soil slurry in land reclamation projects: the vacuum preloading and geotextile tube systems [1]. e vacuum preloading system is briefly illustrated in Figure 1.…”

Strength Characteristic of a Chemical Binder Treated Marine Clay as Compared with the Use of Cement

“…However, marine clay in Singapore has very poor engineering properties according to engineering practice in Changi East reclamation project and a pilot field trial in Jurong Island West Extension reclamation project (He at al., 2016). How to improve the soft soil to enhance its shear strength and reduce the ground settlement in land reclamation becomes a challenge (Chu et al, 2000;2012).…”

Editorial: Challenges and opportunities

“…The first paper by Chu et al (2012) is a review of methods for the treatment of soft and high water content fill materials or sewage sludge. For thick deposit, ultra-soft ground improvement -such as prefabricated vertical drains with vacuum preloading and deep cement mixing -the major difficulty lies in forming a working platform at the ground surface so that ultra-soft ground improvement works can be undertaken.…”