Geotechnical engineering is the branch of civil engineering concerned with the engineering behaviour of earth materials.
It involves the systematic application of techniques that allows construction on, in, or with geomaterials, i.e., soil and rock.
It uses principles of soil mechanics, rock mechanics, and engineering geology to investigate subsurface conditions and materials. It uses principles of soil mechanics, rock mechanics, and engineering geology to investigate subsurface conditions and materials.
Geotechnical operations are of importance with respect to soil and rock sampling, investigating geomaterials properties, controlling groundwater level and flow as well as environmental and hydrological interactions. Foundation engineering, excavations and supporting ground structures, underground structures, dams, natural or artificial fills, roads and airports, subgrades and ground structures, and slope stability assessments are examples of geotechnical engineering applications in practice.
Geotechnical engineering activities are a part of a team effort involving other disciplines including geology, structural engineering, construction management, hydraulics, earthquake and transportation engineers, and other pertinent branches. The final design of any project reflects a collaboration of these professions.
Geotechnical site investigations are needed to gain an understanding of the area in or on which the engineering will take place. Investigations can include the assessment of the risk to humans, property, and the environment from natural hazards such as earthquakes, landslides, soil liquefaction, debris flows, and rock falls.
A geotechnical engineer then determines and designs the type of foundations, earthworks, and pavement subgrades required for the intended structures to be built. Foundations are designed and constructed for structures of various sizes such as high-rise buildings, bridges, medium to large commercial buildings, and smaller structures where the soil conditions do not allow code-based design. Foundations built for above-ground structures include shallow and deep foundations. Retaining structures include earth-filled dams and retaining walls. Earthworks include embankments, tunnels, and sanitary landfills.
