Results
Two 100m+ soil nail and shotcrete walls constructed without complication.
Retained slopes enabled safe construction of the motorway interchange.
Soil nail performance exceeded design requirements during testing.
Client confidence reinforced through proactive planning and adaptability in clay conditions.
Project
Solution
Installation of approximately 850 150mm soil nails up to 14m in length.
Construction of 100 inclined drains to 15m depth.
Application of 1,000m² of reinforced shotcrete facing.
Destructive testing of soil nails demonstrating capacity beyond engineered requirements.
Proactive drilling methodology and tooling selection based on site conditions.
Project
Challenges
Construction of retaining structures on steep cut slopes for a major motorway interchange.
Variable clay ground conditions posing potential drilling complications.
Requirement for rigorous testing and validation of nail performance.
Large volume of soil nails, drains, and shotcrete to be completed efficiently.
Project
Overview
As part of the $850M Transmission Gully Motorway project in New Zealand, steep cut slopes were stabilised to enable construction of a new interchange. Two large soil nail and shotcrete walls, each over 100m long, were constructed with a scope that included extensive soil nailing, drainage, and reinforced shotcrete facing.
The works were delivered successfully despite challenging clay conditions, drawing on specialist experience and methodology selection to manage potential drilling issues.