Slope Stability and Ground Improvement

Site appropriate investigation techniques

In a country with a high proportion of hilly and mountainous terrain and an expanding population, previously unfavoured land on slopes often subject to instability is increasingly being utilised for residential, commercial, industrial, and infrastructure development. Instability may occur as a result of natural factors, may be a consequence of human activity, or may be a combination of both.
 
Our experienced geotechnical engineers and engineering geologists are proficient in the areas of slope stability assessment and the evaluation and design of ground improvement. We have assessed variable and potentially unstable land throughout New Zealand and in many areas of the Pacific Islands. Investigations range from walkover surveys and geomorphic mapping to detailed deep subsurface assessments.  Our experienced staff will advise on the most appropriate investigation technique for specific situations. Stability hazards vary from small slips on domestic sites to landslides hundreds of metres in length, width, and sometimes depth.
 
To support our stability assessment expertise we utilise a variety of computer software to evaluate failure mechanisms, stability improvement, and slope performance in varying conditions.
 
Dependent upon site conditions, measures to improve stability are highly varied and often specialised. Stability improvement options may include:

• Retaining walls

• Inground (palisade) walls

• Surface and subsurface drainage

• Buttressing

• Earthworks

• Slip surface strengthening 

Considerable design and construction experience of these remediation methods allows us to provide advice and recommendations for any scenario requiring slope stability or ground improvement.