Waikato, New Zealand
CMW has completed a geotechnical investigation for a section of SH2 that will be upgraded to 2 lanes in both directions. This will involve widening of the existing road formation (currently 1 lane in both directions) with significant cuts and structural fills up to approximately 10m and 8m deep respectively.
Proposed development will include culvert extensions, new stock / machinery underpasses, new U-turn facilities, retaining walls, new pavements and pavement overlays.
The scope of the geotechnical investigation is designed to address the complex geological conditions along the alignment and involves the following:
- Drilling approximately 100 hand auger boreholes, 7 machine boreholes, 8 cone penetrometer tests (CPT's) with dissipation testing, test pit excavation and groundwater monitoring;
- Development of representative cross sections and long sections through critical parts of the alignment showing the distribution of the various geological (soil and rock) units;
- Presentation of geotechnical design work undertaken and provision of construction recommendations for the project addressing anticipated geotechnical risks, including: global stability analysis and detailed design of cut and fill batters, capacity of natural soils to support fills and fill embankment stability, settlement analysis of recent soft soils under proposed fills, assessment of rock excavatability/rippability, suitability of existing fills, culverts and retaining walls, design of new retaining structures, stream erosion protection measures as required, liquefaction susceptibility of recent alluvial soils and remedial measures if required.
Additional HSSE planning for working within the road corridor, careful management of multiple contractors, soft soil assessment, liquefaction risk and material suitability assessment.
Hand auger location within the road corridor.
Rotary core machine borehole being drilled.
Machine borehole location atop a significant proposed cut.