Integrated engineering-geological investigations for buildings, bridges, roads, utilities and other development projects — from field data collection to design-ready conclusions.
Engineering geological investigations provide essential information about the geological and geotechnical conditions of a site before design and construction. They identify the composition, properties and distribution of soils and rocks, groundwater conditions, and geological processes that may affect a structure. The results form the basis for the reliable assessment of foundation conditions, selection of appropriate design solutions, and safe and efficient construction.
Available archival data for the site and surrounding area are reviewed together with a visual site assessment. The collected information is evaluated and correlated to define the scope, methods and overall programme of the engineering geological investigation.
Project information — including the site plan, building dimensions, number of above- and below-ground floors, anticipated foundations, loads, available drawings and existing geological data — is reviewed to define the required investigation depth, scope and methods.
Field investigation includes borehole drilling, representative sampling of all significant soil and rock layers, and visual logging of the engineering geological profile. Depending on site conditions, field testing may include SPT, CPT, permeability tests, plate load tests and groundwater monitoring. Initial field observations help define the most appropriate laboratory and in-situ testing programme.
Selected soil and rock samples are subjected to laboratory testing to determine their physical and mechanical properties. Standard testing may include moisture content, density, degree of saturation, porosity, shear strength parameters (φ and c) and deformation modulus (E). Rock samples are primarily tested for uniaxial compressive strength. Where required, additional testing, including triaxial tests, may be performed on soils, coarse-grained materials and rocks to obtain project-specific strength and deformation parameters.
Groundwater conditions are assessed during the investigation to determine groundwater occurrence, depth and potential seasonal variation. Where required, groundwater monitoring and permeability testing are carried out to evaluate possible effects on foundations, excavations, drainage requirements and construction conditions.
Field observations, laboratory results and groundwater data are evaluated together to develop an engineering geological model of the site. Soil and rock conditions are interpreted, engineering geological units are defined, and the parameters relevant to foundation design, excavation and construction are established.
The final engineering geological report integrates field and laboratory results, borehole logs, geological sections, groundwater conditions and design parameters. It provides clear conclusions and engineering recommendations required for foundation design, excavation planning and safe construction.
The investigation programme is adapted to the type, scale, loads and foundation conditions of each structure.
Engineering geological investigations for residential, commercial and high-rise buildings, with the programme adapted to building height, basement levels, foundation type and anticipated loads.
Engineering geological investigations for bridges are concentrated at piers, abutments and other foundation locations where structural loads are transferred to the ground. Investigation points are therefore selected locally according to the bridge layout and foundation scheme. Where slopes or valley sides may affect the structure, slope stability assessment is also recommended to identify potential geotechnical risks.
Engineering geological investigations for roads are adapted to changing ground conditions along the route, with particular attention to embankments, cut slopes, weak subgrade soils and drainage conditions. Investigation points are selected to identify sections that may affect pavement performance, earthworks stability and long-term serviceability.
Engineering geological investigations for utility networks are adapted to the alignment, installation depth and type of underground infrastructure. Particular attention is given to trench stability, groundwater conditions, weak or collapsible soils and sections where changing ground conditions may affect construction, installation and long-term performance.
Engineering geological investigations for industrial facilities are adapted to concentrated and variable structural loads, heavy equipment, tanks and process units. Particular attention is given to foundation conditions, differential settlement, vibration-sensitive areas and local zones where ground behaviour may affect the safe and reliable operation of the facility.
Supplementary investigations are carried out when project conditions change or additional geotechnical information is required. They may include extra boreholes, targeted field or laboratory testing, and verification of specific areas affected by revised layouts, new structures, increased loads or uncertainties identified during design and construction.
Engineering geological investigations form the foundation for safe and reliable design. When they are carried out thoroughly and interpreted correctly, potential ground-related risks can be identified before construction begins — helping to prevent costly design changes, construction difficulties and long-term problems during the operation of the structure.