HW1 Bulli Pass - Site 24-04 Slope Remediation

⁠⁠⁠Slope stabilisation works at Site 24-04 on the HW1 Bulli Pass.

This contract is for slope stabilisation works required to remediate two sections of the downslope on Bulli Pass at Site 24-04 following the declared natural disaster rainfall event in 2024. The scope of work is described in detailed design drawings 304001331-C1000 to 304001331-C1018. The scope of works in this contract generally comprises of the following but not limited to:

Zone 2a:

• Setout of works

• Removal of surface vegetation and scaling of loose material for a 50m length x 5m downslope behind the existing guardrail. Vegetation clearing is to include removal of two mature trees on the downslope and grinding of an existing tree stump to be level with the surrounding ground. Scaling works to allow a clean surface without large protrusions or deleterious material.

• Removal of the existing safety barrier and posts and reinstallation of the guardrail on slimline safety barrier immediately behind the existing kerb.

• Excavation and removal of all material required for the construction of the capping beam.

• Installation of 91 soil nails of 9m length over three rows on the downslope, including 3 nails below the existing culvert outlet in a fourth row. The contractor must consider construction stage loading and is responsible for ensuring slope stability during construction. Construction sequencing must include installation of the top row of soil nails (in the capping beam) prior to installation of lower rows of nails to ensure slope stability is maintained for construction plant and road traffic during the day.

• Installation of 8 horizontal drains of 7m length.

• Installation of a reinforced concrete capping beam (0.8m H x 0.65m W) over a 47m length

• Installation of strip drains to the face of the excavated slope at 3m intervals

• Installation of 300m2 of reinforcing mesh and 150mm thick shotcrete to the 47m length x 6.5m slope height.

• Installation of 50m of new thri-beam safety barrier on new posts and base plates on top of the new capping beam, including transition to the existing guardrail on either side.

• Removal of the old safety barrier and filling of the void between the capping beam and existing pavement with stabilised sand

• Milling and paving 50mm depth asphalt for the full lane width between the capping beam and the centreline. 4.5m width x 47m length.

Zone 4:

• Setout of works

• Removal of surface vegetation and scaling of loose material for a 20m length x 5m downslope behind the existing guardrail. Scaling works to allow a clean surface without large protrusions or deleterious material.

• Removal of the existing safety barrier and posts and reinstallation of the guardrail on slimline safety barrier immediately behind the existing kerb.

• Excavation and removal of all material required for the construction of the capping beam.

• Installation of 27 soil nails of 9m length over three rows on the downslope. The contractor must consider construction stage loading and is responsible for ensuring slope stability during construction. Construction sequencing must include installation of the top row of soil nails (in the capping beam) prior to installation of lower rows of nails to ensure slope stability is maintained for construction plant and road traffic during the day.

• Installation of 5 horizontal drains of 7m length.

• Installation of a reinforced concrete capping beam (0.8m H x 0.65m W) over a 20m length

• Installation of strip drains to the face of the excavated slope at 3m intervals

• Installation of 130m2 of reinforcing mesh and 150mm thick shotcrete to the 20m length x 6.5m slope height.

• Installation of 20m of new thri-beam safety barrier on new posts and base plates on top of the new capping beam, including transition to the existing guardrail on either side.

• Removal of the old safety barrier and filling of the void between the capping beam and existing pavement with stabilised sand

• Milling and paving 50mm depth asphalt for the full lane width between the capping beam and the centreline. 4.5m width x 20m length.

Additional details/instructions

Any Price and Non price percentage published under Evaluation/Weighting as part of this Opportunity advertisement is the default setting of a mandatory field, and does not apply to this Opportunity.

Primary contact:

Juliane Latu

juliane.latu@transport.nsw.gov.au

02 4064 0089