City of Kingston – Erosion stabilisation – Emergency Works
Completion of emergency erosion stabilisation works undertaken at the Mentone Foreshore shared path. The works were carried out in response to coastal scour and loss of supporting material beneath the concrete pathway, which had resulted in significant undermining of the slab and the creation of voids beneath the structure. The adopted repair methodology was designed as a temporary stabilisation measure to restore support beneath the pathway, minimise further erosion, and improve public safety pending any future permanent coastal protection works.

City of Kingston – Erosion stabilisation – Emergency Works

Completion of emergency erosion stabilisation works undertaken at the Mentone Foreshore shared path. The works were carried out in response to coastal scour and loss of supporting material beneath the concrete pathway, which had resulted in significant undermining of the slab and the creation of voids beneath the structure.

The adopted repair methodology was designed as a temporary stabilisation measure to restore support beneath the pathway, minimise further erosion, and improve public safety pending any future permanent coastal protection works.

Works Undertaken:

Void Filling Beneath Concrete Slab

  • Inspection identified voids extending beneath the concrete pathway.
  • The cavity beneath the slab was progressively filled with sand stabilised using approximately 5% cement content.
  • Stabilised material was carefully compacted and worked beneath the slab to restore support.
  • Voids ranging from approximately 0 mm to 100 mm in height were filled beneath the pathway for an approximate distance of 1.5 metres behind the pathway edge.

Geotextile Encapsulation System

  • Supply and installation of non-woven geotextile fabric.
  • Geotextile was extended beneath and around the repair area to create a fully
  • encapsulated stabilisation system.
  • The geotextile was positioned to minimise future migration of sand and reduce the potential for further washout.

Sand-Cement Bag Installation

  • Ready-mixed sand-cement bags were installed within the geotextile encapsulation system.
  • Bags were carefully pushed beneath the slab and positioned to maximise support of the undermined edge.
  • Approximately two rows of bags were installed where required to suit actual site conditions.
  • The bags were arranged to achieve continuous support beneath the exposed slab edge.

Gap Elimination and Final Stabilisation

  • Minor gaps remaining between the sand-cement bags and the underside of the concrete slab were filled with additional 5% cement-stabilised sand.
  • This ensured full contact between the repair system and the underside of the slab.
  • The completed repair was designed to minimise unsupported voids and provide a sound temporary support system.

Geotextile Wrapping and Reinstatement

  • Following installation, the geotextile was wrapped around the repair system to fully encapsulate the stabilisation works.
  • The repair area was then covered with a sand ramp and shaped to blend with the surrounding beach profile.
  • The finished profile eliminated trip hazards and protected the repair system from direct exposure.