Excavation And Shoring Failure

Dee Why

The redevelopment of the site in Dee Why required the creation of a multilevel basement car park in sand materials well below the groundwater level.  The redevelopment site was also close to, and in places adjoining existing commercial & residential developments.  Temporary excavation support was by a system of driven steel sheet piles with ground anchors.

After the excavation had been completed to 3 levels, movement of the excavation support was observed in the vicinity of the existing commercial developments, with resultant substantial cracking and damage to the various brick buildings.

SCE was then engaged by the insurer for the various adjoining commercial buildings to advise on the probable cause of failure, and efficacy of the various remedial works being proposed by the project builder.

The results of the SCE investigations indicated that the design & construction of the shoring system, and the anchors in particular, was faulty.  SCE also expressed considerable concerns as to the efficacy of the remedial works proposed by the builder.

The insurer then decided to settle the claims by the commercial building owners, with a view to then recovering its costs from the builder.  However, because of the builder and its associated subcontractors were later placed in receivership, the insurer was never able to recover its costs.