What is Geotechnical Engineering
Geotechnical Engineering is the story of the engineering relationship between humans and earth. It is the science that explains the mechanics of soil and rock and its engineering application to the development of humankind.
History of Geotechnical Engineering
In the early day’s application of geotechnical engineering was based on trial and error method. As time progressed, the more and more scientific approach was taken in Geotechnical Engineering. Various scientist published their fundamental theories on soil mechanics between 1700 to 1900. Karl Terzaghi is considered the father of modern Geotechnics, who published his book on soil mechanics in 1925. Terzaghi, with other professionals from twenty countries, founded the International Society for Soil Mechanics and Geotechnical Engineering.
What does Geotechnical Engineers do?
Geotechnical Engineering is a branch of Civil Engineering. Geotechnical engineering uses the principles of soil mechanics and rock mechanics to investigate the subsurface condition. The field of Geotechnical Engineering and Engineering Geology is closely related and largely overlap. However, the field of geotechnical engineering specializes in engineering, whereas engineering geology specializes in geology. The role of Geotechnical Engineers is very important,as all construction rests on the ground. Soil is a very complex material. That is why the role of Geotechnical Engineers has one of the most challenging tasks of civil engineering.
Geotechnical engineers use principles of soil mechanics to evaluate the stability of natural slopes, cuts and fills, man-made soil deposits, foundation design, dams and retaining walls and many other works of civil engineering.
Foundation Engineering – This is an important aspect of Geotechnical Engineering. It is important to design the foundation to withstand natural and man-made loads. Loads can be vertical or lateral. It is important to know the soil condition before designing the type and depth of foundation required for the structure. In order to know the subsurface soil condition, a geotechnical investigation is required. The process of geotechnical investigation involves drilling through soil or rock, collecting soil samples, testing them in the laboratory. Once the test results come, the Geotechnical Engineer analyses the report, which outlines the soil and rock properties, groundwater condition. Based on the report, the geotechnical engineer analyzes the risk and determines the type of foundation required to build the structure. Based on the recommendation of the Geotechnical Engineer, the structural engineer then designs the structural design of the structure. Geotechnical Investigation for high rise structures or bridges is very important for the structural stability of those structures. That is why it is important to select the right Geotechnical Engineering firm that has prior experience in delivering the project. It is important to involve the Geotechnical Engineer very early in the project so that the owner can eliminate a lot of risks.
A proper Geotechnical Investigation can save the substantial cost of the design and construction of the right type of foundation. Soil characteristic changes with depth as well as horizontal distance. That is why it is very important while doing the investigation to drill at the required depth as well as drill the required number of holes as per the recommendation of the Canadian Foundation Design standard. Sometime the owner might save some Geotechnical Investigation cost but end up spending way more than the anticipated cost during the construction cost. It is very important to have the Geotechnical Investigation done right.
Geotechnical Engineers are also involved in providing material testing for construction support. Geotechnical Engineers analyzes all the field test reports to ensure that the construction is going on as per the project specification. During construction, a confirmatory test for soil compaction is done on-site to ensure that no future settlement happens. While doing concrete, field tests are conducted to ensure that the concrete poured is as per the project specification. After the concrete is poured, seven days and 28 days, tests are conducted on concrete samples collected from the site to ensure that the concrete poured meets the design standard. Asphalt core is taken after the Asphalt is laid and compacted to ensure that the Asphalt laid on site meets the design standard. All laboratory test report is analyzed by the Geotechnical Engineer to ensure that it meets the project specification. Geotechnical Engineers observe proof roll at the site to ensure that the area compacted does not have any soft spot. Pile Load Test is carried out under the supervision of a Geotechnical Engineer.
The role of a Geotechnical Engineer in Civil Engineering is immense, whether it is pre-construction or during the construction. Without a great Geotechnical Engineer, modern-day civil engineering marvel could not have been possible.