A comprehensive study of the site, its soil, rock and overall construction feasibility
As a more detailed approach to site analysis, a Ground Investigation, also known as a Site Investigation, typically entails extracting soil and rock samples for profiling and further testing.
It may also include in situ testing. Extraction is conducted by drilling boreholes or digging trial pits. In situ testing includes intrusive and non-intrusive on-site testing of the soil or rock at its inherent in situ stress, often with little to no disturbance which may alter its behaviour.
Site investigations can also include installing instrumentation for short term or long term monitoring of a site. The Site Investigation includes both geotechnical and geo-environmental aspects of the site to gain confidence in the nature of the soil and reaction to the site intervention.
Samples are sent for various tests, from simple gradings and indicator analysis to advanced geotechnical and chemical testing.
Our role in Site Investigations includes some or all of the following:
- Design: simply providing Site Investigation specifications
- Supervision: overseeing the Site Investigation (may include data collection and core logging)
- Data collection: logging boreholes, profiling trial pits, and obtaining on-site test data
- Interpretation: examining data collected to provide design input
At Jones & Wagener, we have conducted countless Ground / Site Investigations over the last 50 years in investigative, supervising, and consulting capacities.
With years of experience, our teams of qualified geotechnical engineers and geologists can conduct comprehensive, detail-oriented Site Investigations. These assessments evaluate the project’s design limitations and capture the necessary data to aid construction.
In partnership with drilling contractors, we offer a range of services tailored to any project, whether small-scale housing developments or large civil projects.
A thorough Site Investigation is an essential preliminary design tool for any construction project. Moreover, these investigations are often mandated by authorities before construction. In cases where warranties are provided through bodies such as the NHBC or Zurich, projects must comply with specific technical requirements, some of which require thorough Site Investigations.
Intrusive investigation techniques that we commonly use include:
- Trial pitting
- Soakage Testing
- Dynamic Probing
- Dynamic Windowless Sampling
- Cable Percussion Drilling
- Rotary Drilling
- In situ borehole testing
- Standard Penetration Testing (SPT)
- Cone penetration testing (CPT)
- Dynamic cone penetrometer (DCP)
- Disturbed and undisturbed soil sampling
- Water sampling
- Groundwater and ground gas monitoring
On-site testing that we commonly carry out includes:
- California bearing ratio (CBR) testing
- Plate Bearing Testing
- Sand replacement density (SRD) testing
- Geophysics (e.g., Microgravity and Ground Penetrating Radar)
Samples collected during the Site Investigation are sent to a specialist laboratory for a range of tests that may include:
- Moisture content
- Particle Size Distribution (PSD)
- Specific gravity
- Plasticity Index (PI)
- Linear Shrinkage (LS)
- Bulk density
- California Bearing Ratio (CBR)
- Oedometer
- Effective stress triaxial
- Advanced triaxial
- Permeability
- Concrete aggressiveness
Following receipt of all site and laboratory data, and depending on the project requirements, we carry out the following:
