Ground investigation and testing
Expert-defined terms from the Advanced Certificate in Engineering Geology and Soil Mechanics course at LearnUNI. Free to read, free to share, paired with a globally recognised certification pathway.
Ground Investigation and Testing #
Ground Investigation and Testing
Ground investigation and testing are essential components of engineering geology… #
This process involves a comprehensive study of the ground conditions at a site to assess its suitability for a particular project, such as building construction, road infrastructure, or foundation design.
Ground investigation and testing typically involve a combination of fieldwork an… #
The information obtained from ground investigation and testing is used to develop a detailed understanding of the site's geotechnical characteristics, which is crucial for ensuring the safety, stability, and sustainability of engineering projects.
Key Concepts and Terms #
1. Soil Sampling #
The process of collecting soil samples from different depths and locations at a site to analyze their properties, such as composition, density, moisture content, and strength.
2. Geophysical Survey #
A method of investigating the subsurface by measuring the physical properties of the ground, such as electrical resistivity, seismic wave velocity, and magnetic susceptibility.
3. Standard Penetration Test (SPT) #
A common in-situ testing method to determine the relative density and strength of granular soils by driving a split-spoon sampler into the ground and recording the number of blows required to penetrate a certain depth.
4. Cone Penetration Test (CPT) #
An in-situ testing method that involves pushing a cone-shaped penetrometer into the ground to measure the soil's resistance and pore pressure, providing information on soil behavior and strength.
5. Dynamic Cone Penetrometer (DCP) #
A portable device used for rapid in-situ testing of the strength and compaction of soils, particularly in road construction and pavement design.
6. Plate Load Test #
A field test to determine the ultimate bearing capacity of soil by applying a gradually increasing load to a steel plate placed on the ground surface.
7. Permeability Test #
Laboratory testing to measure the rate at which water flows through a soil sample, providing information on the soil's drainage characteristics and suitability for drainage systems.
8. Atterberg Limits #
The water content boundaries of soil at which it transitions from solid to plastic and from plastic to liquid states, as determined by the liquid limit, plastic limit, and shrinkage limit tests.
9. Triaxial Test #
A laboratory test to assess the shear strength and stress-strain behavior of soils under different confining pressures, providing essential data for slope stability analysis and foundation design.
10. Groundwater Monitoring #
The process of measuring and analyzing groundwater levels and quality at a site to assess potential impacts on construction activities, such as excavation, dewatering, and foundation design.
11. Geotechnical Report #
A comprehensive document that summarizes the findings of ground investigation and testing, including site characterization, geotechnical parameters, design recommendations, and risk assessments for engineering projects.
12. Rock Core Sampling #
The process of extracting cylindrical rock samples from boreholes to analyze the physical and mechanical properties of rock formations, such as strength, porosity, and weathering.
13. Pressuremeter Test #
A specialized in-situ testing method to determine the in situ stress-strain behavior of soils and rock masses by applying radial pressure to a borehole and measuring the resulting deformation.
14. Ground Improvement Techniques #
Methods used to enhance the engineering properties of soils, such as compaction, stabilization, grouting, and reinforcement, to increase their load-bearing capacity and reduce settlement.
15. Seismic Refraction Survey #
A geophysical method to determine the subsurface velocity of seismic waves and infer the depth and thickness of soil and rock layers, useful for site characterization and foundation design.
16. Settlement Analysis #
The process of predicting and evaluating the vertical deformation of the ground due to applied loads, such as buildings, embankments, and retaining walls, to ensure structural stability and prevent excessive settlement.
17. Liquefaction Potential #
The susceptibility of loose, saturated soils to lose strength and stiffness during seismic events, leading to rapid ground settlement and instability, which can be assessed through laboratory tests and empirical correlations.
18. Geosynthetics #
Synthetic materials used in geotechnical engineering, such as geotextiles, geogrids, and geomembranes, to improve soil stability, drainage, filtration, and reinforcement in various construction applications.
19. Ground Freezing #
A temporary construction method to stabilize excavations and underground structures by freezing the surrounding ground using refrigeration pipes, creating a frozen soil wall to prevent groundwater inflow and soil collapse.
20. Rock Mass Classification #
Systems, such as the Rock Mass Rating (RMR) and Geological Strength Index (GSI), used to assess the quality and stability of rock masses based on geological, structural, and geomechanical parameters for tunneling, slope stability, and rock engineering projects.
21. Electrical Resistivity Tomography (ERT) #
A geophysical imaging technique to map subsurface variations in electrical resistivity and infer the distribution of soil and rock layers, groundwater zones, and potential contamination plumes.
22. Ground Penetrating Radar (GPR) #
A non-invasive geophysical method to detect buried objects, voids, and geological features in the subsurface by transmitting and receiving electromagnetic waves, useful for utility mapping, archaeological surveys, and geotechnical investigations.
23. Hydraulic Conductivity #
The measure of a soil's ability to transmit water under a hydraulic gradient, determined by permeability tests and used to assess seepage, drainage, and contaminant transport in geotechnical and environmental applications.
24. Shear Strength #
The internal resistance of soil or rock to sliding along a failure plane, characterized by cohesion and frictional resistance, crucial for slope stability, foundation design, and retaining wall analysis.
25. Foundation Engineering #
The branch of geotechnical engineering that focuses on the design and construction of foundations to support structures, transferring loads from buildings, bridges, and infrastructure to the underlying soil or rock strata.
26. Soil Classification #
Systems, such as the Unified Soil Classification System (USCS) and the AASHTO Soil Classification System, used to categorize soils based on particle size distribution, plasticity, and engineering properties for design and construction purposes.
27. Geospatial Analysis #
The use of geographic information systems (GIS) and remote sensing technologies to analyze and visualize spatial data related to ground conditions, land use, environmental factors, and infrastructure planning for engineering projects.
28. Shallow Foundation #
A type of foundation that transfers building loads to the near-surface soil layers, including spread footings, mat foundations, and raft slabs, suitable for low-rise structures with uniform soil bearing capacity.
29. Deep Foundation #
A type of foundation that transfers building loads to deeper soil or rock strata through piles, caissons, or drilled shafts, necessary for high-rise buildings, bridges, and structures with variable or weak soil conditions.
30. Slope Stability Analysis #
The assessment of the stability of natural and man-made slopes against potential failure mechanisms, such as sliding, overturning, and subsidence, using geotechnical principles and numerical modeling techniques.
31. Excavation Support Systems #
Structural systems, such as sheet piles, soldier piles, and soil nails, used to stabilize and retain soil around excavations, trenches, and deep foundations to prevent cave-ins and ground movements.
32. Dilatancy #
The tendency of granular soils to expand and contract under shear stress, affecting their strength, stiffness, and deformation behavior, particularly in sandy and gravelly materials subjected to cyclic loading.
33. Ground Settlement #
The downward movement of the ground surface due to consolidation, loading, or natural processes, which can lead to structural damage, uneven settlement, and safety risks for buildings, roads, and utilities.
34. Soil Stabilization #
Techniques, such as chemical grouting, soil mixing, and lime treatment, used to improve the engineering properties of soils by enhancing strength, durability, and compaction for construction and infrastructure projects.
35. Geotechnical Instrumentation #
Monitoring devices, such as inclinometers, piezometers, and settlement gauges, installed in the ground to measure changes in soil and rock behavior, groundwater levels, and structural performance over time.
36. Rockfall Protection #
Structural measures, such as rockfall barriers, catch fences, and rock bolting, implemented to mitigate the risk of rockfall hazards and protect infrastructure, roads, and buildings from falling rock debris.
37. Compaction Test #
Laboratory testing to determine the optimal moisture content and maximum dry density of soil by compacting samples in standard molds and measuring their volume and weight, essential for earthwork and embankment construction.
38. Ground Improvement #
Methods, such as vibro-compaction, soil nailing, and deep mixing, used to modify the engineering properties of soils and rock masses to increase load-bearing capacity, reduce settlement, and enhance stability for construction projects.
39. Geosynthetic Reinforcement #
The use of geotextiles, geogrids, and geocells to reinforce soil, retain slopes, and stabilize embankments, providing tensile strength, erosion control, and confinement in geotechnical and environmental applications.
40. Subsurface Exploration #
The process of investigating the subsurface conditions of a site through boreholes, test pits, geophysical surveys, and sampling techniques to assess soil and rock properties, groundwater levels, and geological hazards.
41. Undrained Shear Strength #
The shear strength of saturated cohesive soils under rapid loading conditions, determined by laboratory tests, such as the unconfined compression test, and critical for stability analysis of foundations, slopes, and embankments.
42. Rock Mass Discontinuities #
Planar or linear fractures, joints, faults, and bedding planes in rock formations that influence their strength, permeability, and stability, requiring detailed mapping and analysis for rock engineering and tunneling projects.
43. Geotechnical Modeling #
The process of simulating and analyzing the behavior of soil and rock masses using numerical methods, such as finite element analysis (FEA) and distinct element modeling (DEM), to predict ground response and deformation under different loading conditions.
44. Dynamic Compaction #
A ground improvement technique that involves dropping heavy weights onto the ground surface to increase soil density, reduce settlement, and improve bearing capacity for construction of roads, ports, and landfills.
45. Geotechnical Risk Assessment #
The evaluation of potential hazards, uncertainties, and geotechnical challenges associated with a project, such as landslides, liquefaction, and foundation failure, to develop risk mitigation strategies and ensure project safety and success.
46. Geospatial Data Collection #
The acquisition of spatial information, such as topography, land cover, and infrastructure networks, using GPS, LiDAR, drones, and satellite imagery for site characterization, mapping, and analysis in engineering and environmental studies.
47. Groundwater Seepage #
The flow of water through soil and rock formations due to hydraulic gradients, pore pressures, and hydraulic conductivity, leading to soil erosion, slope instability, and groundwater contamination in geotechnical and environmental settings.
48. Shear Wave Velocity #
The speed at which shear waves propagate through soil and rock formations, determined by geophysical surveys, such as seismic refraction and MASW tests, to assess the stiffness, density, and dynamic properties of the ground.
49. Geotechnical Monitoring Program #
A systematic plan for installing and maintaining geotechnical instruments, conducting field tests, and collecting data to monitor ground conditions, construction activities, and structural performance throughout the project lifecycle.
50. Rock Slope Stability #
The analysis and design of rock slopes and cliffs to assess the risk of rockfall, toppling, and wedge failure, considering geological factors, discontinuities, weathering, and stress conditions for safe and sustainable engineering solutions.
51. Groundwater Recharge #
The process of replenishing underground aquifers with surface water through infiltration, percolation, and artificial recharge methods to maintain water resources, prevent land subsidence, and support sustainable development in water-stressed regions.
52. Geohazard Mapping #
The identification, assessment, and mapping of natural hazards, such as landslides, earthquakes, and floods, using geospatial data, remote sensing, and geological surveys to inform land-use planning, disaster risk reduction, and infrastructure resilience.
53. Time #
Dependent Deformation: The gradual settlement, consolidation, and creep of soils and rock masses over time under sustained loads, temperature changes, and environmental conditions, requiring long-term monitoring and prediction for engineering design and maintenance.
54. Ground Improvement Cost #
Benefit Analysis: The evaluation of the economic feasibility and effectiveness of ground improvement techniques, such as soil stabilization, grouting, and deep mixing, considering construction costs, time savings, and long-term performance benefits for infrastructure projects.
55. Seismic Site Response Analysis #
The assessment of ground motion amplification, liquefaction potential, and seismic soil-structure interaction effects on buildings and infrastructure due to earthquakes, using geotechnical modeling, site-specific studies, and seismic hazard analysis.
56. Foundation Settlement Prediction #
The estimation of anticipated vertical movements of foundations and structures based on soil properties, loading conditions, and geotechnical analysis to ensure structural safety, serviceability, and compliance with design requirements.
57. Geotechnical Engineering Software #
Computer programs, such as PLAXIS, FLAC, and GeoStudio, used for analyzing soil-structure interaction, slope stability, foundation design, and geotechnical modeling to optimize engineering solutions, reduce risks, and enhance project efficiency.
58. Groundwater Remediation #
The treatment and cleanup of contaminated groundwater sources using physical, chemical, and biological methods, such as pump-and-treat systems, in-situ bioremediation, and permeable reactive barriers to protect human health and the environment.
59. Geotechnical Forensics #
The investigation of geotechnical failures, such as slope collapses, foundation settlements, and retaining wall failures, to determine the root causes, contributing factors, and lessons learned for improving design practices and risk management in future projects.
60. Soil #
Structure Interaction: The dynamic response and mutual influence between soil and structures, such as buildings, bridges, and tunnels, under loading, vibration, and settlement conditions, requiring careful consideration in foundation design, seismic analysis, and construction planning.
61. Groundwater Monitoring Network #
A system of wells, piezometers, and sensors installed at strategic locations to measure groundwater levels, quality parameters, and flow rates for assessing aquifer behavior, contamination risks, and sustainable water resource management.
62. Geotechnical Database Management #
The organization, storage, and analysis of geotechnical data, such as borehole logs, lab test results, and monitoring records, using digital platforms, GIS, and databases to facilitate data sharing, decision-making, and quality control in engineering projects.
63. Rockfall Hazard Zoning #
The delineation of areas prone to rockfall events based on rock slope stability, geological conditions, and historical incidents, to inform land-use planning, hazard mitigation measures, and emergency response strategies for public safety and infrastructure protection.
64. Ground Improvement Monitoring #
The regular inspection, measurement, and interpretation of ground improvement works, such as compaction, grouting, and reinforcement, to ensure quality control, compliance with design specifications, and long-term performance of engineered structures.
65. Geotechnical Investigation Planning #
The systematic process of defining project objectives, selecting investigation methods, allocating resources, and scheduling fieldwork to collect relevant data on ground conditions, hazards, and geotechnical parameters for informed decision-making in engineering design.
66. Seismic Microzonation #
The mapping of local variations in seismic hazard, ground motion amplification, and site effects due to geological, topographic, and soil conditions for urban planning, building code development, and disaster risk reduction in earthquake-prone regions.
67. Groundwater Modeling #
The numerical simulation of groundwater flow, contaminant transport, and aquifer behavior using mathematical models, such as MODFLOW, MT3DMS, and FEMWATER, to evaluate water resources, pollution risks, and remediation strategies in hydrogeological studies.
68. Geotechnical Specifications #
The detailed requirements, guidelines, and quality standards for geotechnical investigations, testing procedures, design parameters, and construction practices outlined in project documents, contracts, and regulatory codes to ensure project compliance and performance.
69. Geophysical Inversion #
The process of interpreting geophysical data to create subsurface models of soil and rock properties, such as resistivity, velocity, and density variations, using inverse modeling algorithms, regularization techniques, and uncertainty analysis for geotechnical and environmental studies.
70. Groundwater Dependent Ecosystems #
Natural habitats, wetlands, and riparian zones that rely on groundwater sources for water supply, nutrient cycling, and ecosystem services, requiring sustainable management, conservation measures, and hydrological monitoring to preserve biodiversity and ecological balance.
71. Rockfall Risk Assessment #
The evaluation of potential rockfall hazards, rock mass stability, and impact energy on structures, roads, and communities using engineering models, hazard mapping, and risk analysis to develop risk reduction strategies, warning systems, and protective measures.
72. Ground Improvement Design #
The selection, sizing, and detailing of ground improvement techniques, such as stone columns, soil mixing, and jet grouting, based on geotechnical analysis, design criteria, and construction considerations to enhance soil properties and ensure project performance.
73. Geotechnical Instrument Calibration #
The verification and adjustment of geotechnical sensors, data loggers, and monitoring equipment to ensure accuracy, reliability, and traceability of measurements for geotechnical investigations, construction monitoring, and long-term performance assessment.
74. Groundwater Well Design #
The planning and installation of groundwater wells, boreholes, and monitoring points to access aquifers, measure water