Client: Hamilton City Council

Location: Bryce Street, Hamilton

Date: April - September 2023

 

CONTEXT

This project was part of a Hamilton City Council's programme of transport safety and infrastructure improvements completed over a five year period.

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SUMMARY OF WORKS

The project encompassed a new reinforced concrete roundabout, a comprehensive stormwater drainage system upgrade, new footpaths and a durable multi-layered asphalt pavement. Additional improvements included raised speed tables, tactile pavers and upgraded pedestrian crossings.

 

EARTHWORKS

Extensive excavation was required to remove vegetation, concrete structures and traffic islands. Bulk earthworks involved stripping and stockpiling topsoil, removing existing pavement and berms, and importing structural fill for embankments and sub-grade improvement layers. Hydro-vac excavation located and connected existing services.

 

STORMWATER AND DRAINAGE

The stormwater drainage network was upgraded to manage increased water flow and

improve flood resilience. Swale drains were added. Old catch pits were removed and replaced with seven new vertical entry catch pits and five manholes with scruffy domes. More than 300 metres of subsoil drains were installed, supported by a rain garden for stormwater treatment and riprap to protect outlets.

 

PAVEMENT AND SURFACING

The pavement construction included preparing and stabilising subgrades, installing

sub-base layers, and placing premium aggregate. The sub-base consisted of over 2,700 square meters of AP65 material, reinforced with a Gridtex combi-grid. Additional excavation and fill were necessary in areas where the subgrade did not meet design standards.

 

FOOTPATHS

We constructed over 300 square metres of concrete footpaths and 40 square metres of asphaltic concrete paths, with raised pedestrian crossings featuring coloured thermoplastic asphalt. Directional and warning tactile pavers were added at crossings to assist visually

impaired pedestrians. New residential entranceways and berm reshaping were included in the road layout to create a safer and more functional urban environment.

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SURFACING

Asphalt work was crucial to this project. The first two layers used 1800 tons of AC20

HiMod mix over six night shifts. The third layer consisted of 790 tons of EME2 laid in two layers with precise temperature control and rolling patterns, achieving high density with minimal passes.

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The final surface layer consisted of 315 tons of SMA12.5, laid at 55mm. Raised speed tables in each quadrant were completed using AC20 and AC10 mixes. QA measure included Nuclear Densometer (NDM) testing, core sampling, and real-time monitoring of temperature and application rates.

 

TRAFFIC MANAGEMENT

This area had a 6700 VPD count at Gordonton Rd, north of RAB (2019), and 7,900 south of RAB (2019). Work was restricted to 9am to 3pm each day, after which the road fully reopened in the evening. Excavation, backfilling, and temporary sealing were completed daily to meet

these constraints. Pedestrian access was preserved with temporary paths and signage.

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RELEVANCE

This project highlights our ability to undertake traffic infrastructure upgrade and pedestrian safety improvement projects in busy, live traffic locations, and respond to unexpected challenges, without compromising quality of delivery.