Interaction between reclamation and civil works

Land reclamation is generally undertaken for a specific purpose for example, the extension or construction of a port facility, the construction of an industrial estate or the development of a housing area. The type of usage and, hence, the structures to be built on the reclamation dictate, to a great extent, the functional and technical requirements to be considered during the design and construction of the fill mass. 

The civil works constructed on reclaimed land generally include structures (e.g. buildings, storage tanks, bridges), infrastructure (e,g. runways for airports, roads, railways, pipelines/cables), and structures located along the boundary (e,g. quay walls). Each type of structure will have its own interaction with the reclaimed land, usually in terms of required behaviour of the fill mass. 

All structures are subject to foundation design. In some cases piled foundations are preferable. Heavy structures with very strict specifications regarding (differential) settlement will normally require a piled foundation when constructed on reclaimed land overlying soft subsoil. Small sized structures of limited weight can generally be supported by shallow foundations. Based on a technical and economical evaluation of the structural and reclamation design, the decision whether a piled foundation is required should be made in an early phase of the project. 

When piled foundations are foreseen for structures, compaction of the fill could be limited. A too high level of compaction would yield problems when driving piles to their design depth. In case of cast-in-situ piles, very high energy levels may be required to reach the design tip elevation. 

When shallow foundations are foreseen in the design, then an adequate compaction of the fill may be required to guarantee the bearing capacity with sufficient safety. 

---