The behavior of earth materials is the subject of geotechnical engineering, a branch of civil engineering. Professionals in this field examine the physical and chemical properties of the soil and rock layers that make up the earth. They use this data to create foundations and earthworks structures for buildings, roads, and a variety of other projects.
Geotechnical engineering’s goal is to create soil stabilization systems that are safe for people. This could include ensuring that a structure stands firm on shaky ground or preventing major roads from being impacted by earthquakes and landslides. Geotechnical engineers may also be involved in projects involving underwater soils, such as marinas or offshore platforms.
The geotechnical design process begins with a subsurface investigation, which includes the collection of soil samples via test pits or bores. The properties of the soil, such as its stability, the presence of air or rock pockets, and the chemical makeup of the earth, will then be examined by geotechnical engineers. This investigation enables them to assess the environmental impact of disturbing the soil as well as the steps that should be taken to prepare the site for construction.
After the subsurface work is finished, a geotechnical engineer can use the findings of this study to design stable footings and foundations. These structures, which are made of steel, concrete, or masonry, are buried to support and distribute the building’s weight. Engineers calculate the load of both the building materials and the people inside to create accurate designs. These systems must also allow for the building’s settlement over time, as well as ground movements and weather impacts. The larger and more complex the foundation system is, the more unstable the soil at a project site is.
Earth support structures for roads, tunnels, dams, and other projects are also designed by geotechnical engineers. Support systems must be used whenever the earth is moved or excavated to prevent the remaining earth from caving in or becoming unstable. Concrete or steel retaining walls can be used in earthworks systems to physically hold back the soil and prevent it from collapsing or cave-ins. Tie-backs or piles, which are steel pins that connect loose sections of earth to more stable ones, are another popular method. Workers may also be protected by temporary earthworks structures during excavation and underground work.
To work in the field of geotechnical engineering, one must typically hold both a bachelor’s and a master’s degree in engineering. While some universities may offer specialized geotechnical programs, the vast majority of students will only be able to find general civil engineering programs. Candidates may find work in the field after graduation, working under the supervision of a licensed engineer. A Professional Engineer (P.E.) license in civil or geotechnical engineering is required to perform geotechnical design work without supervision. The engineer must have several years of relevant work experience and then pass a state-administered engineering exam to obtain this license.