Geotechnical Services
We provide geotechnical services to a wide range of sectors.
PDP provides geotechnical services to a wide range of clients in sectors including pipelines and other lifelines, land development (residential/commercial/industrial), three waters, quarries and mining, water retaining structures including dams, ponds and stop banks, large/primary industry, transport (roads/rail/ports/airports), energy including renewables and petroleum, and solid waste. We also provide specialist advice including emergency response, consent reviews and forensic geotechnical engineering.
Services that we provide:
Engineering Geology
- Mapping – land-based, aerial imagery, UAV (Un-personed Aerial Vehicle or drone), geospatial analysis and digital remote sensing (photogrammetry/LIDAR (Light Detection and Ranging) and InSAR (Interferometric Synthetic Aperture Radar))
- Geomorphology
- Landslides assessments
- Surface and subsurface erosion – including geophysics interpretation
- Rock slopes
- Faults
- Aggregate quarry resources and road construction materials
Geohazards and Lifelines
- Geohazard identification and risk assessment for lifelines, infrastructure and mining/quarrying including high-pressure gas/petroleum products and water pipelines. This type of work is crucial post a Civil Defence event such as the recent Nelson & Northland floods.
- Corridor hazard, route selection and options assessments
- Climate change implications
- Landslide, soil slope and rock slope stability assessments
- Coastal cliff hazard and risk assessments
- Emergency response and assessment
Remedial & Detailed Design
- Landslide stabilisation – drainage, buttress/retention, shear keys, soil nails
- Rock slopes – rock anchors, bolting, shotcrete, mesh, abseil rock scaling, rockfall catch fences, rockfall bunds
- Ground improvement/problem soils – liquefiable ground, re-use of existing materials - sustainability
- Geosynthetic applications – including geogrid reinforced gravel rafts
- Deep foundation/excavation support and temporary support – sheet piles
- Earth retaining structures - retaining walls, gabions, MSE walls
- Dams, embankments, ponds, canals, tailings facilities and waste rock disposal
- Stream and coastal erosion protection
- Earthworks specifications
- Erosion and sediment control
- PS1 (Design) and PS2 (Design Review) sign off and tender evaluation
Construction Monitoring
- Remedial works procurement (tender) process
- Engineer To the Contract (ETC)
- Contractor liaison, construction supervision/monitoring and as-builting
- PS4 sign off
Geotechnical Monitoring
Monitoring for geohazards, dams and remedial works
- Movement networks (survey, manual and automated)
- Piezometers and transducers
- Inclinometers and extensometers
- Rainfall gauges
- Drain and stream flow recording
- Remote monitoring systems
Geotechnical Investigations
- Desktop review and mapping
- Perform/supervise/log hand augers, scala penetrometer, drilling, CPT, test pits/open excavations and geophysical (surface and downhole)
- In situ sampling and testing - permeability, nuclear densometer, compaction trials, clegg hammer
- Out-sourced laboratory testing including acid sulphate soils
Ground Models, Stability Assessments and Geotechnical Reporting
- Landslides in all geological terranes
- Rock slopes – cuttings, quarries, open pit mines, rock mass classification
- Kinematic assessments including rockfall analysis
- Seismic assessments - liquefaction induced ground settlements, lateral spreading/stretch, fault rupture risk
- Subsurface and surface erosion – including tomos
- Deep and shallow excavations/foundations and piles
- Earth dams, embankments, ponds, canals - condition assessments and optimizing of existing structures, breach modelling
- Rivers and streams – erosion, flooding, accretion surveys and stop banks
- Mining waste rock stack/dump design (co-disposal), tailings dam surveillance, safety and stability risk assessments
- Dewatering drawdown and settlement, seepage and inflow
- Resource delineation for aggregate quarries and roading construction materials
- Land development foundations, retention (retaining walls) and ground improvement – residential/commercial/industrial
- Road foundation assessments - green and brown fields
- Ground support, HDD, pipe jacking
Solid Waste
- Site Investigation
- Waste assessments
- Landfill engineering design
- Liner design – natural and geosynthetic
- Management plans
- Bond assessment
Emergency Event Response and Specialist Advice
- Rapid incident/event response
- Forensic geotechnical engineering
- Insurance claims post failures
- Resource consent reviews
- Climate change risk assessments – geohazards
Andy Smith
Technical Director - Geotechnics
Christchurch
See Bio
Andy Smith
Technical Director - Geotechnics
Christchurch
Andrew has over 20 years of experience and leads the geotechnical team in the PDP Christchurch office. He has been involved in projects whilst at PDP including foundation design, dam break assessments, landfill stability, settlement analysis (static, liquefaction induced), slope stability assessments and earthworks design for a contaminated land encapsulation project. Andrew is proven in utilising his broad technical knowledge and experience in providing robust cost-saving solutions. He also has experience in contaminated land assessments which enables him to provide the multi-disciplinary advice required.
Before PDP Andrew worked as an Engineering Geologist on a range of projects from open cast mining/quarry high wall stability assessments, residential/commercial subdivisions and building consent reviews and has acted as an expert witness on several geotechnical-related projects.
Andrew is a Professional Engineering Geologist with Engineering New Zealand, a Chartered Geologist with the Geological Society of London, and a member of the New Zealand Geotechnical Society.
David Poh
Technical Director - Geotechnics
Auckland
See Bio
David Poh
Technical Director - Geotechnics
Auckland
David obtained his PhD in Civil Engineering from the University of Birmingham, UK in 2004. Since then he has been working as a geotechnical engineer and has over 15 years of experience. He was involved in design work, construction supervision, and project management of infrastructure, buildings and land development projects in New Zealand, Singapore and the United Kingdom. He specialises in deep excavations and tunnelling projects. In addition, he has experience in numerical modelling looking at the soil-structure interaction of earth retention systems. He was involved in several building basement projects in Auckland in terms of planning, design, construction and project management.
He is a member of the following institutions: NZ Geotechnical Society, NZ Society for Earthquake Engineering, NZ Tunnelling Society, International Society for Soil Mechanics and Geotechnical Engineering and International Society for Rock Mechanics.
Gerald Strayton
Technical Director - Geotechnics
Hawke's Bay
See Bio
Gerald Strayton
Technical Director - Geotechnics
Hawke's Bay
Gerald is a civil engineer specialising in geotechnics for the waste industry. He joined PDP in 2001 after immigrating to New Zealand from South Africa and has over 30 years of experience, working initially as a contractor before moving into consulting. Gerald has been involved in the investigation, assessment and remediation of several existing and closed landfills as well as the assessment of geotechnical structures such as dams and ponds for various projects in the water and wastewater fields.
In addition, he has extensive experience with the design and detailing of municipal and industrial landfills, tailings dams and small water dams. Gerald is a member of the New Zealand Geotechnical Society and regularly attends conferences relating to waste engineering and in particular the NZSOLD Symposiums and conferences.
Neil Crampton
Technical Director - Geotechnics
Auckland
See Bio
Neil Crampton
Technical Director - Geotechnics
Auckland
Neil is an engineering geologist/hydrogeologist specialising in engineering geology for corridor projects, hydrogeology model development, groundwater investigation/monitoring and contaminated groundwater projects.
Having over 25 years of experience, Neil has worked in a wide range of geological terrains throughout New Zealand and on several projects overseas. He is passionate about developing hydrogeological models for project applications involving mining, water retaining structures, geothermal and contaminated sites as well as gas pipeline corridor route selection, risk assessment and remediation.