Geotechnical Engineers analyze the physical properties of the earth, for example the soil, bed-rock and groundwater, to determine the structural engineering requirements of construction projects. They take soil and rock samples, analyse these, and provide advice to civil and structural engineers, architects, construction personnel and landscapers on the most appropriate tools, methods and materials with which to undertake construction in an area.
All manner of infrastructure, including houses, high rise office towers, roads, bridges, dams and tunnels need their proposed site, and sometimes the surrounding areas, to be analysed to ensure their construction plans meet required engineering standards. These standards assure the soundness and safety of the proposed structure before the project is developed.
A Typical Geotechnical Project
A typical geotechnical engineering project begins with a review of project needs to define the required material properties, followed by an investigation of soil, rock, and bedrock and how these properties will interact with the proposed structure. This will usually involves a geotechnical investigation that requires a Geotechnical engineer to:
• Calculate the magnitude of the loads to be supported;
• Perform Geotechnical investigations to explore the subsurface of the proposed construction site;
• Identify soil parameters through field and lab testing and, on the basis of the findings;
• Design, or make recommendations about the design of building foundations, so they are constructed in the safest and most economical manner possible.
The Importance of Structural Foundations
The foundation of a piece of infrastructure transmit the weight bearing load from the structure to the earth. Geotechnical engineers design the foundations based on the load characteristics of the structure and the properties of the soils and/or bedrock on the site.
The primary considerations for foundation support are bearing capacity, settlement, and ground movement beneath the foundations. Bearing capacity is the ability of the site soils to support the loads imposed by buildings or structures.
Subsurface Geotechnical Investigation
To obtain information about the soil, rock and groundwater conditions below the surface, some form of subsurface exploration is required. For this to happen, geotechnical engineers use various methods to obtain relevant samples so they can determine the physical properties of the soils and rocks at the site.
Laboratory testing is then performed on soils to measure a wide variety of its properties and these results are then used by geotechnical engineers to make appropriate design and footing recommendations.